sustainable construction material.pdf
DESCRIPTION
Sustainable materials for building construction.TRANSCRIPT
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It is a practice of increasing efficiency with which buildings use resources-energy, water and materials while
reducing building impact on human health and the environment.
INTRODUCTION TO SUSTAIBLE MATERIALS
Green building materials are composed of renewable, rather than nonrenewable resources. Green materials are
environmentally responsible because impacts are considered over the life of the product. Depending upon
project-specific goals, an assessment of green materials may involve an evaluation of one or more of the criteria
listed below.
Sustainable materials are materials used throughout our consumer and industrial economy that can be produced
in required volumes without depleting non-renewable resources and without disrupting the established steady-
state equilibrium of the environment and key natural resource systems. Such materials vary enormously and
may range from bio-based polymers derived from polysaccharides, or highly recyclable materials such as glass
that can be reprocessed an indefinite number of times without requiring additional mineral resources.
THE PURPOSE OF THIS STUDY
Materials are the stuff of economic life in our industrial world. They include the resource inputs and the product
outputs of industrial production. How we handle them is a major determinant of true economic efficiency, real
prosperity, social justice, our Personal health, and the health of the natural environment. Materials are,
moreover, far more than resources or products. They are gifts of nature, and substances of Gaias Body. How
we relate to materials in their production and their consumption is one of the best barometers of our
fundamental relationship to that which gives us life. Not Coincidentally, it reflects our relationship to ourselves,
our creativity, our work and possibilities for self-actualization and community development.
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This dissertation is about building materials: about how we use them now, how they might be used more
appropriately, and the process of getting from here to there. Our current use of materials is running down
natural systems, destroying community, debasing work, and suppressing all kinds of possibilities for real
development. To remedy this, we need to conserve materials, reduce their unnecessary use, produce them
more benignly, make them last longer, and recycle and reuse them. We also need to Develop community
consumer initiatives and regulatory processes to support these Reforms.
AIM
Aim of this dissertation is to study materials for sustainable construction and make an eco-friendly environment.
OBJECTIVES
1. To study about the different type of sustainable building materials.
2. To study about how to make a building sustainable.
3. To study the Material selection criteria.
4. To study how to make a building environment friendly.
DEFINITION OF SUSTAINABILITY BRIEFLY
More and more of us are convinced that we would have to do something else on the field of architecture to
provide our environment. But what and how should we build? According to our current attitude, the task of an
architect is to display demands of society in space but they should not specify such demands. As architects, due
to our multifarious skills, we can have an overview on the creation and maintenance of a built environment as a
whole. In the designing part of architectural process, when we should get to know different fields of life. We
need to look into everything related to our project, to create a suitable, functionally relevant space. Nice to
notice the relationship between a well- designed building and its surroundings, whether old or new building is to
be considered.
"A building is not just a place to be. It is a way to be," and another quote Each building must respond to
Nature, and every building must have its own Nature. (Frank Lloyd Wright )
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Sustainable architecture means a new attitude, it uses research results about the environment, the biology and
human ecology and it tries to use these results in the construction technology. Sustainability is based on a
simple principle: Everything that we need for our survival and feeling of comfort, either directly or indirectly, is
in our natural environment, humans and nature can exist in productive harmony, that permits fulfilling the
social, economic and other requirements of present and future generations. Along these points, sustainability
and the sustainable development itself have three important pillars( economy, environment, society) which
together form a unit and create the essential of sustainability.
Few words in the building design and in the construction process have been so poorly used as that of sustainable
design and green architecture, that it has created barriers to make sense this expression. In the dictionary the
word sustainable is defined that something maintained, but it doesn't indicate its relation to the natural world.
According to major part of the literature, the house-man-environment connection points are the following:
architectural formation, location, materials, construction techniques, energy and material flows.
"The building structures of sustainable architecture are made according to theoretical exigences of sustainability
and support the construction-ecological and construction biological-operation during its whole life cycle. "
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This is a definition of the sustainable materials and structures according to Lnyi Erzsbet. Along with this
philosophy outlined, that building structures can be fitted to the built framework of sustainable philosophy if:
they are made of in-situ, local materials
renewable, recyclable, non-toxic materials
they require "closed" production technologies built upon circular processes, and gentle
implementation and maintenance techniques also involving human resources
they can economize with energy use and air moisture content
they are able to increase and utilize environmental resources
ENVIRONMENTALLY-FRIENDLY BUILDING DESIGN- USING SUSTAINABLE MATERIALS
The building design is a process of assembling different materials, whenever you buy them as a product, grow
them, find them on site or dig them. We have many technologies and possibilities for the best decision of the
existing situation, but first of all, besides the prices and the other management things, we should consider how
our way of choosing impacts our environment. A modern green building has to be a low construction impact
while being energy efficient, long lasing, non toxic and aesthetics. Sometimes the mass-produced materials
seem to be the right choice to serve these goals, but also we have to take into consideration, how and where they
are produced, and how it is after the building's life cycle. For the environmentally-friendly buildings it is also a
demand, that they should not pollute their surroundings after using. In the vernacular architecture for instance, it
was a common practice, that after the death or moving out of the inhabitants, the walls (from clay, or other
natural materials) just left alone, and it got back slowly to the nature. That means, its materials can be integrated
to the environment.
Further the designing part, we should support the environmentally-friendly attitude by our choosing as well.
During the construction of buildings, the architects should think holistically about the materials and the whole
structure too. Sustainable design is an approach to design , a holistic approach looking all elements as a part of a
bigger whole. A building is as strong as its weakest component, then for instance strong walls and weak
foundation add up weak walls. A most important thing about a structure, trumping material choices and
aesthetics, is that they must work together as a unit. Besides considering the properties the cost of the materials
are also important for the constructor and for the consumer as well by choosing. We can find a paradox, that the
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originally cheap materials could be more expensive on the market. Although the regional products are the most
economic and cheap ones, they are appeared much more expensive, than the usual ones, however they have
significantly higher energy content, they are often not so healthy or not re-used. Sustainable building Materials
Energy MJ/kg Density kg /m3 Concrete (in-situ- structure) 11.1 2400 Brick (common) 3.0 1700 Clay bricks
2.5 Insulation (Rockwool) 16.80 24 Expanded Polystyrene Insulation 88.6 15-30 Polyurethane insulation 101.5
30 Wool insulation 20.9 25 Clay tile 6.5 1280 Straw bale 0.91 100-110 Rammed earth 0.7 1540 Rammed earth
(no added cement) 0.45 1460 Chart 1_Embodied energy can be cheaper and sometimes slightly more expensive,
it has no or just a low hidden costs (the sustainable buildings would not have any hidden-costs according to its
definition). For the first time we would chosen just the well-known and so-called modern products, however,
the sell prize does not contain the other costs (energy, transportation, environmental deterioration and other
effects). This is non-renewable energy which is used for new materials production, extraction, transportation
and manufacturing, is called embodied energy. Depending on the material, it may be very different. It has
become a popular practice to regard the embodied energy as summary of the cradle-to-gate, which includes all
energy (in primary form) until the product leaves the factory gate, and the cradle-to-site, which includes all of
the energy consumed until the product has reached the building site. Another point which we should bear in
mind by choosing, the studies of the historical techniques.
Humans have been building strong structures since ancient times. Rewinding back in time, everyone knew how
to build a house, as houses were built from local materials, adopting parents and grandparent experiences. Many
solutions have been already worked out also for myriad climatic situations and material combinations.
Unfortunately those experiences are wrapped into the most of the past, because it does not help in developing of
modern materials and the developing industry is pushing out the natural materials from the construction markets
with their easy and fast mounting. But it seems the occurring of damaging processes in the environment
(climate change, green house effect, oil crisis, smog in the developed cities and so on) In the last century people
have used more non-renewable energy resources than over all the thousands of years since its earliest
beginnings. These reasons made people think, take certain measures and they tend to be more and more
enthusiastic about doing something to protect our Earth.
WHAT IS A GREEN BUILDING?
Green building, or sustainable design, is the practice of increasing the efficiency with which buildings and their
sites use energy, water, and materials, and reducing building impacts on human health and the environment over
the entire life cycle of the building. Green building concepts extend beyond the walls of buildings and can
include site planning, community and land use planning issues as well.
Green building materials offer specific benefits to the building owner and building occupants:
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Reduced maintenance/replacement costs over the life of the building.
Energy conservation.
Improved occupant health and productivity.
Lower costs associated with changing space configurations.
Greater design flexibility.
Building and construction activities worldwide consume 3 billion tons of raw materials each year or 40 percent
of total global use. Using green building materials and products promotes conservation of dwindling
nonrenewable resources internationally. In addition, integrating green building materials into building projects
can help reduce the environmental impacts associated with the extraction, transport, processing, fabrication,
installation, reuse, recycling, and disposal of these building industry source materials.
WHY GREEN BUILDING IS IMPORTANT
The growth and development of our communities has a large impact on our natural environment. The
manufacturing, design, construction, and operation of the buildings in which we live and work are responsible
for the consumption of many of our natural resources.
The importance of this is it lessen the consume of energy and the pollution as well because the more we use
nonrenewable energy the higher the risk of pollution.
Environmental Benefits
Enhance and protect biodiversity and ecosystems
Improve air and water quality
Reduce waste streams
Conserve and restore natural resources
Economic Benefits
Reduce operating costs
Improve occupant productivity
Enhance asset value and profits
Optimize life-cycle economic performance
Social Benefits
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Enhance occupant health and comfort
Improve indoor air quality
Minimize strain on local utility infrastructure
Improve overall quality of life
Goals of Green Building
Energy efficiency
Green buildings often include measures to reduce energy consumption both the embodied energy required to
extract, process, transport and install building materials and operating energy to provide services such as
heating and power for equipment.
As high-performance buildings use less operating energy, embodied energy has assumed much greater
importance and may make up as much as 30% of the overall life cycle energy consumption. Studies such as
the U.S. LCI Database Project show buildings built primarily with wood will have a lower embodied energy
than those built primarily with brick, concrete, or steel.
To reduce operating energy use, designers use details that reduce air leakage through the building envelope (the
barrier between conditioned and unconditioned space). They also specify high-performance windows and extra
insulation in walls, ceilings, and floors. Another strategy, passive solar building design, is often implemented in
low-energy homes. Designers orient windows and walls and place awnings, porches, and trees to shade
windows and roofs during the summer while maximizing solar gain in the winter. In addition, effective window
placement (day lighting) can provide more natural light and lessen the need for electric lighting during the
day. Solar water heating further reduces energy costs.
Onsite generation of renewable energy through solar power, wind power, hydro power, or biomass can
significantly reduce the environmental impact of the building. Power generation is generally the most expensive
feature to add to a building.
Water efficiency
Reducing water consumption and protecting water quality are key objectives in sustainable building. One
critical issue of water consumption is that in many areas, the demands on the supplying aquifer exceed its
ability to replenish itself. To the maximum extent feasible, facilities should increase their dependence on water
that is collected, used, purified, and reused on-site. The protection and conservation of water throughout the life
of a building may be accomplished by designing for dual plumbing that recycles water in toilet flushing or by
using water for washing of the cars. Waste-water may be minimized by utilizing water conserving fixtures such
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as ultra-low flush toilets and low-flow shower heads. Bidets help eliminate the use of toilet paper, reducing
sewer traffic and increasing possibilities of re-using water on-site. Point of use water treatment and heating
improves both water quality and energy efficiency while reducing the amount of water in circulation. The use of
non-sewage and greywater for on-site use such as site-irrigation will minimize demands on the local aquifer.
Materials efficiency
Building materials typically considered to be 'green' include lumber from forests that have been certified to a
third-party forest standard, rapidly renewable plant materials like bamboo and straw, dimension stone, recycled
stone, recycled metal (see: copper sustainability and recyclability), and other products that are non-toxic,
reusable, renewable, and/or recyclable. For concrete a high performance or Roman self-healing concrete is
available. The EPA (Environmental Protection Agency) also suggests using recycled industrial goods, such as
coal combustion products, foundry sand, and demolition debris in construction projects. Energy efficient
building materials and appliances are promoted in the United States through energy rebate programs.
Operations and maintenance optimization
No matter how sustainable a building may have been in its design and construction, it can only remain so if it is
operated responsibly and maintained properly. Ensuring operations and maintenance(O&M) personnel are part
of the project's planning and development process will help retain the green criteria designed at the onset of the
project.Every aspect of green building is integrated into the O&M phase of a building's life. The addition of
new green technologies also falls on the O&M staff. Although the goal of waste reduction may be applied
during the design, construction and demolition phases of a building's life-cycle, it is in the O&M phase that
green practices such as recycling and air quality enhancement take place.
Waste reduction
Green architecture also seeks to reduce waste of energy, water and materials used during construction. For
example, in California nearly 60% of the state's waste comes from commercial buildings[40] During the
construction phase, one goal should be to reduce the amount of material going to landfills. Well-designed
buildings also help reduce the amount of waste generated by the occupants as well, by providing on-site
solutions such as compost bins to reduce matter going to landfills.
To reduce the amount of wood that goes to landfill, Neutral Alliance (a coalition of government, NGOs and the
forest industry) created the website dontwastewood.com. The site includes a variety of resources for regulators,
municipalities, developers, contractors, owner/operators and individuals/homeowners looking for information
on wood recycling.
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When buildings reach the end of their useful life, they are typically demolished and hauled to landfills.
Deconstruction is a method of harvesting what is commonly considered "waste" and reclaiming it into useful
building material. Extending the useful life of a structure also reduces waste building materials such as wood
that are light and easy to work with make renovations easier.
To reduce the impact on wells or water treatment plants, several options exist. "Greywater", wastewater from
sources such as dishwashing or washing machines, can be used for subsurface irrigation, or if treated, for non-
potable purposes, e.g., to flush toilets and wash cars. Rainwater collectors are used for similar purposes.
Centralized wastewater treatment systems can be costly and use a lot of energy. An alternative to this process is
converting waste and wastewater into fertilizer, which avoids these costs and shows other benefits. By
collecting human waste at the source and running it to a semi-centralized biogas plant with other biological
waste, liquid fertilizer can be produced. This concept was demonstrated by a settlement in Lubeck Germany in
the late 1990s. Practices like these provide soil with organic nutrients and create carbon sinksthat remove
carbon dioxide from the atmosphere, offsetting greenhouse gas emission. Producing artificial fertilizer is also
more costly in energy than this process.
CONCEPT
The Green Building building concept is gaining importance in various countries, including India. These are
the buildings that ensure that waste is minimized at every stage during the construction and operation of the
building, resulting in low costs, according to the experts in the technology.
The technique associate with the Green Building include measures to prevent erosion of soil, rainwater
harvesting, use of solar energy, preparation of usages of water, recycling of waste water and use of world class
energy efficient practices. A similar concept is natural building, which is usually on smaller scale and tends to
focus on the use of natural materials that are available locally.
MATERIAL/PRODUCT SELECTION PROCESS
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Before understanding the process of material/product selection, it is important to know the entire process of a
construction project. As indicated in figure, any project of this kind mainly contains seven phases. In the first
programming phase, the project has just started to be planned and the owner has only a general concept about
the project. Also all potential participants have to decide whether to join in this project and get ready for
bidding. In the second phase, schematic design, the project is handed to the architects and, with the assistance of
the owner the architects finish the schematic design of the project. Then, in the third phase, the architects detail
the design drawings and provide enough information needed for the construction phase. Afterwards, the
architects are responsible for detailing all their works in documents, which is handed out to the contractors.
Then, according to the documents, contractors prepare bids for their work and present them to the owner. Once
a contractor is selected and is being awarded for the construction work the construction of the project begins.
After the successful construction, the project can be occupied by the users.
The most important decisions on material/product selection are always made in the schematic design phase.
This process continues to a lesser extent in the following phases. Usually, there are three steps of
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material/product selection: research, evaluation and selection. All of the technical information of materials such
as geometric properties, LEED features and testing results is collected in the first step. And learning technical
information of different materials becomes crucial in this step. The second step involves confirmation of the
technical information and more importantly compare different materials/products with the same functions. The
final step selection often involves the use of individual criteria including the LEED rating system to make the
final decision. The architect should be the one who makes the final decision about every product, including
green products and the one who takes the most responsibility for material selection. In reality, the leading
architect teams up with the specification writer and other architects like interior architects. The leading architect
mainly concerns the visual design of the entire building. Since many green products are relatively new, only the
architect can perform significant research or find verification that the product is suitable and code-compliant.
The Interior architect makes interior design and selects materials for interior use. The specification writer often
helps architects with materials selection by collecting and classifying the information of materials. When the
green product is suitable to use, the specification writer can incorporate that product in master specification and
use it on other projects. Whenever possible and based on the contractual project arrangement, the contractor can
give suggestions/recommendations to help architect when he or she didnt have enough information or
experience about the materials and products. Moreover, because of the contractors professional experiences
about construction, it is possible for them to check whether the products are used for the right purpose. Also,
during the process of material/product selection, the expert of materials characteristics must be the product
manufacturers. To assist the architect, specification writer, or contractor with all their knowledge about
materials.
Overall material/product selection criteria:
Resource efficiency
Indoor air quality
Energy efficiency
Water conservation
Affordability
Resource Efficiency can be accomplished by utilizing materials that meet the following criteria:
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Recycled Content: Products with identifiable recycled content, including postindustrial content with a
preference for postconsumer content.
Natural, plentiful or renewable: Materials harvested from sustainably managed sources and preferably
have an independent certification (e.g., certified wood) and are certified by an independent third party.
Resource efficient manufacturing process: Products manufactured with resource-efficient processes
including reducing energy consumption, minimizing waste (recycled, recyclable and or source reduced
product packaging), and reducing greenhouse gases.
Locally available: Building materials, components, and systems found locally or regionally saving energy
and resources in transportation to the project site.
Salvaged, refurbished, or remanufactured: Includes saving a material from disposal and renovating,
repairing, restoring, or generally improving the appearance, performance, quality, functionality, or value of a
product.
Reusable or recyclable: Select materials that can be easily dismantled and reused or recycled at the end of
their useful life.
Recycled or recyclable product packaging: Products enclosed in recycled content or recyclable packaging.
Durable: Materials that are longer lasting or are comparable to conventional products with long life
expectancies.
Indoor Air Quality (IAQ) is enhanced by utilizing materials that meet the following criteria:
Low or non-toxic: Materials that emit few or no carcinogens, reproductive toxicants, or irritants as
demonstrated by the manufacturer through appropriate testing.
Minimal chemical emissions: Products that have minimal emissions of Volatile Organic Compounds
(VOCs). Products that also maximize resource and energy efficiency while reducing chemical emissions.
Low-VOC assembly: Materials installed with minimal VOC-producing compounds, or no-VOC mechanical
attachment methods and minimal hazards.
Moisture resistant: Products and systems that resist moisture or inhibit the growth of biological
contaminants in buildings.
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Healthfully maintained: Materials, components, and systems that require only simple, non-toxic, or low-
VOC methods of cleaning.
Systems or equipment: Products that promote healthy IAQ by identifying indoor air pollutants or
enhancing the air quality.
Energy Efficiency can be maximized by utilizing materials and systems that meet the following criteria:
Materials, components, and systems that help reduce energy consumption in buildings and facilities.
Water Conservation can be obtained by utilizing materials and systems that meet the following criteria:
Products and systems that help reduce water consumption in buildings and conserve water in landscaped
areas.
Affordability can be considered when building product life-cycle costs are comparable to conventional
materials or as a whole, are within a project-defined percentage of the overall budget.
SUSTAINABLE MATERIALS
WOOL BRICK
SUSTAINABLE CONCRETE
SOLAR TILES
PAPER INSULATION
TRIPLE-GLAZED WINDOWS
BAMBOO
ADOBE
CLAY
CORK
RECYCLED RUBBER
STRAW
FLYASH BRICKS
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WOOL BRICKS
Wool bricks reinforced with wool to obtain a composite that is more sustainable, non-toxic, using abundant
local materials, and that mechanically improve the bricks' strength.
The wool fibers were added to the clay material used in the bricks, using alginate conglomerate, a natural
polymer found in the cell walls of seaweed. The mechanical tests carried out showed the compound to be 37%
stronger than other bricks made using unfired stabilized earth.
Advantages of environmentally-friendly bricks
The researchers studied the effect of reinforcing various soil types with sheep's wool, and arrived at various
conclusions. "These fibres improve the strength of compressed bricks, reduce the formation of fissures and
deformities as a result of contraction, reduce drying time and increase the bricks' resistance to flexion."
This piece of research is one of the initiatives involved in efforts to promote the development of increasingly
sustainable construction materials. These kinds of bricks can be manufactured without firing, which contributes
to energy savings. According to the authors: "This is a more sustainable and healthy alternative to conventional
building materials such as baked earth bricks and concrete blocks."
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SUSTAINABLE CONCRETE
Concrete is a friend of the environment in all stages of its life span, from raw material production to demolition,
making it a natural choice for sustainable home construction. Here are some of the reasons why, according to
the Portland Cement Association and the Environmental Council of Concrete Organizations:
Resource efficiency. The predominant raw material for the cement in concrete is limestone, the most abundant
mineral on earth. Concrete can also be made with fly ash, slag cement, and silica fume, all waste byproducts
from power plants, steel mills, and other manufacturing facilities.
Durability. Concrete builds durable, long-lasting structures that will not rust, rot, or burn. Life spans for
concrete building products can be double or triple those of other common building materials.
Thermal mass. Homes built with concrete walls, foundations, and floors are highly energy efficient because
they take advantage of concretes inherent thermal massor ability to absorb and retain heat. This means
homeowners can significantly cut their heating and cooling bills and install smaller-capacity HVAC equipment.
Reflectivity. Concrete minimizes the effects that produce urban heat islands. Light-colored concrete pavements
and roofs absorb less heat and reflect more solar radiation than dark-colored materials, such as asphalt, reducing
air conditioning demands in the summer.
Minimal waste. Concrete can be produced in the quantities needed for each project, reducing waste. After a
concrete structure has served its original purpose, the concrete can be crushed and recycled into aggregate for
use in new concrete pavements or as backfill or road base.
Concrete
SOLAR SHINGLES
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Solar Shingles, also called photovoltaic shingles, are solar cells designed to look like conventional slate
or asphalt shingles. There are several varieties of solar shingles, including shingle-sized solid panels that take
the place of a number of conventional shingles in a strip, semi-rigid designs containing several silicon solar
cells that are sized more like conventional shingles, and newer systems using various thin film solar
cell technologies that match conventional shingles both in size and flexibility. Solar shingles are manufactured
by several companies, but the two main manufacturers of solar roof shingles are Dow and CertainTeed.
Solar shingles are photovoltaic cells, capturing sunlight and transforming it into electricity. Most solar shingles
are 12 by 86 inches (300 by 2,180 mm) and can be stapled directly to the roofing cloth. When applied they have
a 5 by 86 inches (130 by 2,180 mm) strip of exposed surface. Different models of shingles have different
mounting requirements. Some can be applied directly onto roofing felt intermixed with regular asphalt shingles
while others may need special installation.
Solar shingled roofs have a deep, dark, purplish-blue color, and therefore look similar to other roofs in most
situations. Homeowners may prefer solar shingles because they avoid having large panels on their roofs.
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COST
Older solar shingle designs were more expensive to install than traditional PV panels, but new, more efficient
designs such as thin-film copper indium gallium selenide (CuInxGa(1-x)Se2) cells can be installed in 10 hours,
compared with the 22 to 30 hours required for the installation of traditional panels. The lower cost of
installation dramatically reduces the cost of solar power implementation.[1]
All photovoltaic power is produced in the form of direct current (DC). The standard in homes is alternating
current (AC). Therefore part of the cost of installation of solar shingles is the price of an inverter to convert DC
to AC.
The most inexpensive way to install solar shingles is to use the grid as a backup source of electricity. Backup
storage, in the form of batteries, is expensive, adds complexity to the installation, and is uneconomic in any
large scale. Battery backup units require an array of additional hardware. This includes batteries, battery
enclosures, battery charge controllers, and separate sub panels for critical load circuits. However, grid power is
only useful as a backup system if it is available when solar power is not.
SOLAR TILES
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PAPER/CELLULOSE INSULATION
The word cellulose comes from the French word for a living cellule and glucose, which is sugar. Building
insulation is low-thermal-conductivity material used to reduce building heat loss and gain, and reduce noise
transmission. Cellulose insulation is plant fiber used in wall and roof cavities to insulate, draught proof and
reduce noise.
There are several types of insulation that can be used in walls, floors, and ceilings.
Insulation materials play a primary role in achieving high energy efficiencies in buildings. There has been
concern over the health impacts of the material constituents of insulation ever since the problems associated
with asbestos became apparent, followed by the banning of urea formaldehyde based insulation. Some health
concerns have spread to potential inhalation of fiberglass and cellulose insulation fibers and dust.
HISTORY
Cellulose is among the oldest types of building insulation material. Many types of cellulosic materials have
been used, including newspaper, cardboard, cotton, straw, sawdust, hemp and corncob. Monticello was
insulated with a form of cellulose. Modern cellulose insulation, made with recycled newspaper using grinding
and dust removing machines and adding a fire retardant, began in the 1950s and came into general use in the US
during the 1970s.
PAPER INSULATION PANELS
Made from recycled newspapers and cardboard, paper-based insulation is a superior alternative to chemical
foams. Both insect resistant and fire-retardant thanks to the inclusion of borax, boric acid, and calcium
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carbonate (all completely natural materials that have no associations with health problems), paper insulation can
be blown into cavity walls, filling every crack and creating an almost draft-free space.
PRODUCTS
Four major types of loose-fill cellulose products have been developed under a variety of brand names. These are
generally characterized as dry cellulose, spray applied cellulose, stabilized cellulose, and low dust cellulose.
These types are used in different parts of a building and for different reasons.
Dry cellulose (loose fill)
Dry cellulose is used in retrofitting old homes by blowing the cellulose into holes drilled into the tops of the
walls. It can also be blown into a new wall construction by using temporary retainers or netting that is clamped
in place then removed once the cellulose has reached the appropriate density. This form of application does
settle as much as 20% but the stated R-value of the cellulose is accurate after settling occurs. In addition, a
dense-pack option can be used to reduce settling and further minimize air gaps. Dense-pack places pressure on
the cavity, and should be done by an experienced installer.
Loose fill in walls is an antiquated technique of using cellulose in wall cavities. The home performance industry
and its accrediting bodies support the dense-pack standard of insulating wall cavities, which does not settle.
This method stops the stack effect and convective loops in wall cavities.
Spray-applied cellulose (wet-spray cellulose)
Spray-applied cellulose is used for applying cellulose to new wall construction. The differences are the addition
of water to the cellulose while spraying as well as adding some kind of moisture retardant such as chlorine to
prevent mold cultures. In some cases the insulation might also mix in a very small percentage of adhesive or
activate a dry adhesive present in the cellulose. Wet-spray allows application without the need for a temporary
retainer. In addition, wet-spray allows for an even better seal of the insulated cavity against air infiltration and
eliminates settling problems. Wet-spray installation requires that the wall be allowed to dry for a minimum of
24 hours (or until maximum of 25% moisture is reached) before being covered.
Stabilized cellulose
Stabilized cellulose is used most often in attic/roof insulation. It is applied with a very small amount of water to
activate an adhesive of some kind. This reduces settling and decreases the amount of cellulose needed. This can
prove advantageous at reducing the overall weight of the product on the ceiling drywall helping prevent
possible sag. This application is ideal for sloped roofs and has been approved for 5:12 (41.66%) slopes.
Low-dust cellulose
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The last major type of cellulose insulation on the market is low-dust variety. Nuisance levels of dust are created
during application of most types of dry insulation causing the need for simple dust masks to be worn during
installation. This kind of cellulose has a small percentage of oil or similar dust dampener added. This may also
be appropriate to homes where people are sensitive to newsprint or paper dust (though new dust will not be
created after installation).
ADVANTAGE OF PAPER INSULATION
Thermal performance
The thermal performance of loose filled cellulose compares favorably to other types of low cost insulation, but
is lower than that of polyurethane and polyisocyanurate foams. The thermal conductivity of loose-fill cellulose
is approximately 40 mW/mK (an R-value of 3.8 per inch) which is about the same as or slightly better than
glass wool or rock wool. This doesnt represent the whole picture of thermal performance. Other important
aspects are how well the building envelope is seals from air infiltration, convective airflows, and thermal
bridging.
Cellulose is very good at fitting around items in walls like pipes and wiring, leaving few air pockets that can
reduce the overall efficiency of the wall. Dense pack cellulose can seal walls from air infiltration while
providing the density to limit convection, when installed properly. The University of Colorado School of
Architecture and Planning did a study that compared two seemingly identical test structures, one insulated with
cellulose and the other with fiberglass. The cellulose insulation lost 26.4% less heat energy over time compared
to the fiberglass insulation. It also was shown to tighten the structure more than 30%. Subsequent real world
surveys have cellulose performing 20-30% better at reducing energy used for heating than fiberglass.
Compared to closed cell, Polyurethane foam insulation (R=5.5 to 6.5 per inch), cellulose has a lower R-value
per inch, but is much less expensive; foam has a higher cost per equivalent R-value.
Long-term cost savings
Annual savings from insulating vary widely and depend on several factors, including insulation thickness,
original wall performance, local climate, heating/cooling use, airtightness of other building elements and so on.
One installer claims cellulose insulation "can save homeowners 20 to 50 percent on their utility bills".
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Sound insulation
Insulation reduces sound travelling through walls and between floor levels. Cellulose provides mass and
damping. This reduces noise in 2 ways, it reduces the lateral movement of sheetrock and attenuates the passage
of sound along cavities. Cellulose is approximately three times denser than fiberglass, providing a slight
improvement in sound reduction.
Mold and pest control
The borates in cellulose insulation provide added control against mold. Installations have shown that even
several months of water saturation and improper installation did not result in mold.
It is a common misconception that the mere presence of crude borates in cellulose insulation provides pest
control properties to the product. While boric acid itself does kill self-grooming insects if ingested, it must be
presented to an insect in both sufficient concentration and in an ingestible form in order to achieve insect
fatality. Proper testing of products containing borates must be performed in order to determine whether dosage
and presentation are sufficient to kill insects. Once tested, registration with the EPA as a pesticide is required
before a product may be touted as having pesticidal capabilities in the USA.
Fire retardation
The borate treatment also gives cellulose the highest (Class I) fire safety rating. Many cellulose companies use a
blend of ammonium sulfate and borate.
Vapor barrier
A vapor barrier may not be needed with cellulose insulation. For example, recent studies have shown that air
movement is the primary method by which excessive moisture can accumulate in mild marine climate such as
Portland, OR, USA. An insulation that fills the wall cavity completely (such as cellulose or foam) can help
prevent moisture problems. Recommendations against using vapor barriers with cellulose insulation are
supported by studies, even though they classify cellulose as vapor permeable.
In addition, cellulose acts to distribute moisture throughout the cavity, preventing the buildup of moisture in one
area and helping to dry the moisture more quickly. Cellulose manufacturers do not recommend the installation
of a vapor barrier with cellulose.
Most US city codes will require a vapor barrier for any external wall. Most US cities will consider an appeal of
the requirement if proper reasoning is provided. In March 2008 The US city of Portland, Oregon, approved an
appeal to waive the requirement for a vapor barrier/retarder when using cellulose insulation. The appeal can be
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viewed in the Portland Bureau of Development Services search form by searching for appeal ID 4996.
Fundamental to any appeal is mentioning that recent studies show air movement is the primary problem for
vapor, that cellulose is an effective barrier to air movement, and that cellulose acts to diffuse vapor.
DISADVANTAGES
Cellulose has a few disadvantages. As compared to other insulation options, the R-value of 3.6 to 3.8 per inch is
good but not the best. Cost per R-value is good. Spray foam has many of the same benefits as wet-spray
cellulose (such as sealing the cavity), while having advantages in R-value and rigidity and air sealing. Many
spray foams utilize an environmentally harmful blowing agent, such as Enovate HFC, cellulose does not.
Dust
Cellulose contains some small particles which can be blown into the house through inadequate seals around
fixtures or minute holes.
Installation expertise and building codes
In some areas it can be difficult to locate installers that are experienced with cellulose. An experienced installer
understands how to correctly dense-pack loose fill dry cellulose, how to best apply stabilized (partly wet)
cellulose on sloped surfaces, and the proper time required for wet-spray cellulose to dry.
As with other non-batt insulation, US city and regional/state building codes may not be updated for cellulose
insulation. Homeowners should call the city to verify that the insulation will be approved, and it may be
necessary to provide product specifications to the city. This is not difficult, and the installer and the
manufacturer should both be willing to handle this process, saving the homeowner any true effort.
Slumping
If improperly installed, loose fill cellulose could settle after application. In some situations this could leave
areas of wall uninsulated. With correct training in installation methods and quality control techniques this is
ruled out by installing to tested densities preventing any future settlement.
Weight
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For a given R-value, loose cellulose weighs roughly three times as much per square foot as loose
fiberglass. Ceiling structures should be inspected for signs of weakness before choosing a material for insulating
the ceilings of existing structures.
Offgassing
Many cellulose companies use a blend of ammonium sulfate and borate for fire retardation. Although
ammonium sulfate is normally odorless, unexplained emission of ammonia and a resulting ammonia smell has
been found in some cases.
Mold
There is some evidence of increased mold infestation inside buildings insulated with wet spray dense pack
cellulose especially when used with a vapor barrier.
ENVIORMENTAL PROPERTIES
Recycled content
Cellulose is composed of 75-85% recycled paper fiber, usually post-consumer waste newsprint. The other 15%
is a fire retardant such as boric acid or ammonium sulphate. Cellulose has the highest recycled content of any
insulation available. For example, fiberglass has a maximum amount of 50% recycled content.
Low toxicity and environmental impact of raw materials
The non-recycled components of cellulose insulation are still environmentally preferable to the raw materials of
most other insulation types. Unlike foam insulations, many of which use HFC or HCFC blowing agents which
have global warming potential higher than that of carbon dioxide, cellulose does not produce significant
gaseous emissions.
Toxicity of the raw materials of insulation types is typically highest during manufacture or installation. Neither
is a significant issue with cellulose.
OSHA states that cellulose is a dust nuisance, requiring a dust mask during installation. This compares very
favorably to the potential NIOSH cancer risk of fiberglass.
Embodied energy
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The embodied energy of cellulose insulation is the lowest of the popular insulation types. It requires 20 to 40
times as much energy to produce furnace-made insulation materials compared to cellulose. Cellulose is made by
electrically powered machines while mineral insulation is made in fuel powered furnaces, reducing this
advantage to a degree, as electricity generation is less than 50% efficient. If electricity is sourced from
renewable energy sources, the efficiency of electric production does not matter as efficiency is not a
precondition for sustainability. Cellulose is made with locally available paper, while mineral insulation factories
ship materials and products over greater distances.
Cellulose insulation uses borates for fire retardation. Borates are a non-renewable mined product.
Insulation is green
All insulation helps make buildings more energy efficient. Using cellulose insulation can contribute to obtaining
LEED credits in the US Green Building Council certification program. It can earn credit in two categories: the
Energy and Atmosphere energy performance category and the Materials and Resources recycled content
category.
PRODUCT SAFETY
Cellulose insulation can be very dusty during installation and it is recommended that a standard dust mask be
worn while working. There is slight concern over the off gassing of ink from the newspapers but the material is
sealed behind walls, and no studies have shown this as an issue.
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TRIPLE GLAZED WINDOWS
Triple glazing is today standard for energy efficient windows. The difference between double glazing is vast,
particularly because of the extra air gap between the panes. Triple glazing is the solution for large windows, that
used to mean major heat loss in winter. Triple glazed windows now make it possible to build with light and
space, which is widely used in modern homes.
The rough and ready method of comparing the energy performance of windows is to use the U value
measurement, just as we do with walls, floors and roofs. Traditional windows, with a single pane of glass in
them, have a U value in excess of 5. Double glazing used to score over 3, but, over the years, the manufacturing
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process has undergone a number of improvements and currently the Building Regulations insist that any
window you install today should have a U value no worse than 1.6.
Triple glazing is widely used in cold climate countries like Sweden and Norway, and the ultra-low energy
PassivHaus standard requires triple glazed windows with a U value of no more than 0.8. To get a window with
such a low U value, you have to not only switch to triple glazing but also insulate the frame itself, as well as
using more expensive manufacturing techniques the gas krypton tends to be used, instead of argon.
The key benefits are really to do with comfort. If you insulate the walls, roof and floor of a house, and you
ignore the glazing, you end up with cold spots surrounding the windows at night, which cause draughts, draw
heat away from you if you sit next to them, and result in streams of condensation running down the panes. So,
in essence, the standard of glazing has to match the standard of the insulation elsewhere in the house, so that the
warm wrapping around the house performs consistently.
Which is where triple glazing comes in. Because if double glazing makes a modern house more comfortable to
live in, triple glazing makes it even more so.
The physics involved here have been worked out in Germany by the PassivHaus Institute. It has shown what
happens to surface temperatures on various forms of glazing when it gets really cold outside, and the internal air
temperature is designed to be at 21C:
Next to a single glazed window, the internal surface temperature is around 1C.
Next to a double glazed window (2000 vintage), the surface temperature is around 11C.
Next to a modern, energy-efficient double glazed window, the surface temperature is 16C.
Next to a triple glazed window, with a Centre-pane U value of just 0.65, the temperature is 18C.
So you can see that whilst a double glazed window is perfectly adequate, a triple glazed one is just that much
more comfortable, because it hangs onto heat just that little bit better.
Benefits of Triple Glazed Windows
Offer a more rigid and strength window
Great selection on extreme weather
Excellent resistance to condensation problems
Helps reduce sound transmission
Better energy saver than regular and double glazed windows
Triple glazed windows can decrease relativeheat loss
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Increases thermal comfort inside the building
A combination of double glazed windows and triple glazed windows can be used with the building
orientation to obtain excellent results.
Insulated hollow frames can increase triple glazed windows performance.
Cons of Triple Glazed Windows
The weight of triple glazed windows can be a problem with weaker sash materials.
Triple glazed casements have width limitations
Slightly higher prices than double glazed window
Some casement type windows could have a restriction when opened.
If an existing structure has little or no wall insulation, triple glazed windows are not recommended.
ADOBE
Adobe is probably one of the most sustainable elements that can be used to construct buildings. It is made from
clay and dirt, which are abundant in the earth and do not require a lot of processing in order to harvest. Other
natural materials, such as straw or even dung, can be added to the clay in order to harden and insulate it better.
Although adobe is not necessarily something that can be taken out of the ground, it is a very simple process that
makes it even more useful for an environmentally friendly building. In order to make adobe bricks one must
mix water with the clay and other items until it can be shaped into a solid block. Rather than using the concrete
red bricks, adobe is an awesome alternative that will be the exact thing that your house needs to be more energy
efficient and sustainable.
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INSULATION WITH ADOBE
For people who are a little more worried about using adobe to build their constructs, it can also be used for
insulation. Many parts of traditionally built houses are poorly insulated, which leaves them susceptible to
energy inefficiencies. Spending more money on energy costs can be avoided by simply using adobe for
insulation in the house.
In addition to saving money, this is also beneficial for the planet. It is a sustainable practice to cut the usage of
fossil fuels and other energy sources that are bad for the environment. For this reason, using adobe as insulation
is not only cheap and cost effective, but it is also great for the environment. These are both things that anyone
involved in the sustainable movement would appreciate.
Nonetheless, many people do not use adobe because it seems like a primitive way to insulate or construct a
building. This mindset is outdated and should be quickly reversed in society. Thankfully, the sustainable
movement has made great strides in the past few decades to help people overcome their prejudices to many
environmentally friendly materials.
CLAY
A material that many people use in order to promote sustainable building is clay. This is one of the most, if
not the most, sustainable material that anyone can use for a construction project. The best part about the clay
is the lack of processing that is required to get it out of the ground and then on to your home. This saves
energy, emissions, and makes it a material that is worthwhile for use in any sustainable construction project.
Below is an introduction to clay and the uses that are possible for your building project.
Clay Harvest
One reason that clay is such a great sustainable material is because of the harvesting method that makes it so
easy to produce. Taking clay out of the ground is one of the main steps and probably the most processing that
goes on throughout the entire system. Once the clay has been taken out of the earth one can add water in order
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to shape the clay into bricks or even add a few other sustainable materials, such as straw or sand, in order to
strengthen the actual material.
Nonetheless, much of the reason that sustainable is good for the environment is because it is a product of earth
that should be utilized when constructing out buildings. More importantly, the lack of processing required to get
the clay out of the ground is an indicator of the energy efficiency that many sustainable products are capable of
providing.
Building with Sustainable Clay
As mentioned previously, clay is one of the best materials that one can use in order to build a sustainable
construction. The clay is usually added to straw, sand, and then water in order to make bricks that are used as
walls. These walls are not subject to becoming moist and breaking apart as there are still homes in Wales that
maintain their structure after hundreds of years of rain.
In addition to using as a solid building material, it is also acceptable to use clay as an insulator to the weather.
This will allow homes to maintain their heat during the winter months and maintain the comfortable
temperatures during the summer months. More importantly, it is a natural way to provide energy efficiency so
buildings are not using too much in order to maintain the proper temperature.
Clay is a sustainable construction material that has been used by humans for centuries. It is so easy to excavate
from the ground that there is little processing that is required, which means that energy and many time-
consuming processes are spared. As a construction material, the clay acts as a perfect brick for building
outdoors no matter where you live. Additionally, the bricks can be used for insulation in order to save money on
many traditional methods. Saving money on the energy bill is also a possibility given that buildings will be
much more energy efficient with this kind of insulator. It is obvious that the sustainable construction movement
is on the right track.
CORK
Like hemp and rubber, cork is another sustainable material that has been used in the United Kingdom and the
rest of the world to build sustainably constructed structures for many years. Cork is a unique material that is
harvested mainly in Portugal for a number of things. However, within recent years many people in the
sustainable movement have found uses for cork in building projects.
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Cork is a great insulating material. It keeps warmer in the winter and cooler in the summer. The energy
efficiency aids in cutting energy bills in the winter. It is much more energy efficient than either Armstrong
laminate flooring or discount wood flooring. Cork is also good for sound insulation.
Cork as Bricks
There are a number of sources of sustainable bricks to choose from. Some people use larger brick options, such
as straw, which can be placed in bales and stacked into walls. However, other people use adobe, which is a clay
and straw mixture with water in order to seal their homes or buildings. These two forms of bricks have a long
history and humans have been using them for many centuries. However, new research and technology has
allowed people to build certain buildings with cork.
It is no surprise that the sustainable movement has gained so much traction over the past few years. Within only
a short period of time they have been able to introduce completely new materials that are not only
environmentally friendly, but also cost efficient. One of the biggest problems with the environmental movement
is that it is seen as inefficient for building cheaply. However, this has been proven false time and time again.
Cork is yet another material that can be used instead of the unsustainable materials that are currently being
utilized for construction projects.
Harvesting of Cork
One great aspect of cork is that it is so easy to harvest and is in great abundance. Most uses for cork are not very
substantial, such as wine stoppers. There are many hectares of cork in the world, which makes it an abundant
resource that will regenerate far faster than humans can use it for construction projects. At the current rate there
is too much cork in Portugal and many other places in the world, which is unlike many other products, like
timber.
Timber is usually commercially cut in huge swathes which disrupt the ecosystem and contribute to deforesting
on a large scale. It is unfortunate that these events happen, but the sustainable community has started using cork
in greater quantities in order to reverse this trend.
PROPERTIES AND USE
Cork's elasticity combined with its near-impermeability makes it suitable as a material for stoppers.
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Cork's bubble-form structure and natural fire retardant make it suitable for acoustic and thermal insulation in
house walls, floors, ceilings and facades. The by-product of more lucrative stopper production, corkboard is
gaining popularity as a non-allergenic, easy-to-handle and safe alternative to petrochemical-based insulation
products which are flammable and emit highly toxic fumes when burned.
Sheets of cork, also often the by-product of stopper production, are used to make bulletin boards as well as floor
and wall tiles.
Granules of cork can also be mixed into concrete. The composites made by mixing cork granules and cement
have lower thermal conductivity, lower density and good energy absorption. Some of the property ranges of the
composites are density (4001500 kg/m), compressive strength (126 MPa) and flexural strength (0.5
4.0 MPa).
STRAW
For many years straw has always been a bi-product that was not used effectively. Due to the popularity of the
sustainable movement there have been great strides to utilise straw as a building material for people all over the
United Kingdom and the rest of the world. There are uses for straw for construction purposes and insulation,
which makes it a versatile option in comparison with fibreglass and many other materials that are not
sustainable. Additionally, straw is an incredibly cheap option for people who want to build their homes on a
budget. There is nothing better than maintaining a budget and still helping the environment tremendously as
well.
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Straw Bales Construction
In many cases straw bales are created in order to provide construction materials for certain projects. Simple
homes can be created with straw bales and even more sophisticated buildings can use the bales for some areas.
Although the strength is lacking in comparison with some other materials, if made correctly, the bales of straw
can actually provide great protection against the elements. More importantly, they can provide the necessary
construction benefits with sustainable methods rather than using out of date products that are harmful to the
environment and the overall goals of sustainability.
There are a number of homes, including upper-scale buildings, that have been built purely with straw bales.
There is a higher susceptibility to rot when using straw as a sustainable material, but the availability, cost, and
renewable resource all make it worth the effort and risk.
Straw as Insulation
While construction is certainly possible on some smaller scales, it is often a good idea to use straw as insulation
at the very least. Compared with many different forms of insulation that are currently used, straw is much more
effective because it can be packed much tighter than others. Nonetheless, it has not received the level of praise
that it should, given the unique capability to seriously enhance the energy efficiency of a home.
Sustainable materials are an important aspect of constructing in a responsible manner, but so is energy
efficiency. People who have homes build out of sustainable materials are not helping if they must spend large
amounts of energy in order to heat or cool buildings. Instead, using straw can provide a great insulation that will
make the goals of sustainability easier to realize.
Sustainable Material Straw
There are many reasons to use sustainable materials in order to build your home. Using straw to build the home
completely will save you a lot of money, but will also offer you the ability to protect the environment and
embark on the task of maintaining sustainability in your life. However, for those who would like to take less
risk and use straw for insulation over traditional methods, then that is a great alternative as well.
The insulation is perfect because it can increase the sustainability of a home while also working on energy
efficiency. Protecting the earth and environment are the ultimate goals of sustainability, which is why straw is
so useful.
THERMAL PROPERTIES
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Compressed straw bales have a wide range of documented R-value. R-value is a measurement of a materials
insulating quality, higher the number the more insulating. The reported R-value ranges from 17-55 depending
on the study, differing wall designs could be responsible for wide range in R-value. Bale walls are typically
coated with a thick layer of plaster, which provides a well-distributed thermal mass, active on a short-term
(diurnal) cycle. The combination of insulation and mass provide an excellent platform for passive solar building
design for winter and summer.
Compressed and plastered straw bale walls are also resistant to fire.
METOD
Straw bale building typically consists of stacking rows of bales on a raised footing or foundation, with a
moisture barrier or capillary break between the bales and their supporting platform. There are two types of
straw-bales commonly used, those bound together with two strings and those with three. The three string bale is
the larger in all three dimensions. Bale walls can be tied together with pins of bamboo, rebar, or wood (internal
to the bales or on their faces), or with surface wire meshes, and then plastered, either with a cement-based mix,
lime-based formulation, or earth/clay render. The bales may actually provide the structural support for the
building ("load-bearing" or "Nebraska-style" technique), as was the case in the original examples from the late
19th century. The plastered bale assembly also can be designed to provide lateral and shear support for wind
and seismic loads.
Alternatively, bale buildings can have a structural frame of other materials, usually lumber or timber-frame,
with bales simply serving as insulation and plaster substrate, ("infill" or "non-loadbearing" technique), which is
most often required in northern regions and/or in wet climates. In northern regions
OVERVIEW
Straw is a renewable resource that acts as excellent insulation and is fairly easy to build with. Care must be
taken to assure that the straw is kept dry, or it will eventually rot. For this reason it is generally best to allow a
straw bale wall to remain breathable; any moisture barrier will invite condensation to collect and undermine the
structure. Other possible concerns with straw bale walls are infestation of rodents or insects, so the skin on the
straw should resist these critters. There are two major categories of building with straw bales: load-bearing and
non-load bearing. A post and beam framework that supports the basic structure of the building, with the bales of
straw used as infill, is the most common non-load bearing approach. This is also the only way that many
building authorities will allow. While there are many load- bearing straw bale buildings that are standing just
fine, care must be taken to consider the possible settling of the straw bales as the weight of the roof, etc.
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compresses them. Erecting bale walls can go amazingly quickly, and does not take a lot of skill, but then the
rest of the creation of the building is similar to any other wood framed house.
In fact straw bale houses typically only save about 15% of the wood used in a conventionally framed house. The
cost of finishing a straw bale house can often exceed that of standard construction, because of the specialized
work that goes into plastering both sides of the walls. The result is often worth it though, because of the superior
insulation and wall depth that is achieved
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RECYCLED RUBBER
There are many uses for rubber and none of them are more apparent than in sustainable construction. Although
many people think of rubber as a synthetic product, it is actually harvested from the rubber tree, which
obviously a renewable resource. Recycled rubber is even more useful because it does not require additional
harvesting of rubber, but instead just builds upon already used materials. Even though rubber in itself is already
a renewable resource that can be sustainable, using rubber is one of the best ways to complete any construction
project in an environmentally conscious way.
Rubber Effectiveness and Sustainability
Unlike many other types of trees, the rubber tree provides a great product that can be used in a number of ways.
Although in construction there are limits to how rubber can be used, the tree nonetheless provides an effective
and sustainable material for building.
Rubber is easy to install as flooring for buildings, which makes it a great alternative to other types of materials
that are not sustainable or efficient for the home. The quality is what makes the product so fascinating for your
home. The rubber is resistant to fading in comparison to many other types of flooring and people who smoke
will find the cigarette burn resistance even more compelling.
Overall, one of the most effective types of flooring that can be used in the modern age is rubber. In the United
Kingdom many building projects have already converted to the material in an effort to become more efficient,
long lasting, and sustainable.
Recycled Rubber
Another reason to use rubber in the home is that it can be recycled for consumption. Whereas many other types
of sustainable resources are just produced naturally with a moral regenerative mindset, the rubber is actually
recycled so that you do not have to worry about how it is harvested from the tree. There are no trees that get
tapped or harvested when recycled rubber is used.
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For people who are truly trying to build a sustainable home, there is nothing better than using recycled
materials. There are types of aluminum and others that are recycled for use in the home, but using natural
products multiple times is one of the best ways to build a sustainable construction.
TIRE PYROLYSIS
The pyrolysis method for recycling used tires is a technique which heats whole or shredded tires in a reactor
vessel containing an oxygen-free atmosphere. In the reactor the rubber is softened after which the rubber
polymers break down into smaller molecules. These smaller molecules vaporize and exit from the reactor.
These vapors can be burned directly to produce power or condensed into an oily type liquid, generally used as a
fuel. Some molecules are too small to condense. They remain as a gas which can be burned as fuel. The
minerals that were part of the tire, about 40% by weight, are removed as a solid. When performed well a tire
pyrolysis process is a very clean operation and has nearly no emissions or waste.
The properties of the gas, liquid, and solid output are determined by the type of feedstock used and the process
conditions. For instance whole tires contain fibers and steel. Shredded tires have most of the steel and
sometimes most of the fiber removed. Processes can be either batch or continuous. The energy required to drive
the decomposition of the rubber include using directly fired fuel (like a gas oven), electrical induction (like an
electrically heated oven) or by microwaves (like a microwave oven). Sometimes a catalyst is used to accelerate
the decomposition. The choice of feedstock and process can affect the value of the finished products.
TIRE-DERIVES PRODUCTS
Tires can be reused in many ways, although again, most used tires are burnt for their fuel value. In a 2003 report
cited by the U.S. EPA, it is stated that markets ("both recycling and beneficial use") existed for 80.4% of scrap
tires, about 233 million tires per year. Assuming 22.5 lbs per tire, the 2003 report predicts a total weight of
about 2.62 million tons from tires.
One stage of tire recycling involves the production of alternate products for sale. New products derived from
waste tires generate more economic activity than combustion or other low multiplier production, while reducing
waste stream without generating excessive pollution and emissions from recycling operations.
Construction materials. Entire homes can be built with whole tires by ramming them full of earth and
covering them with concrete, known as Earthships. They are used in civil engineering applications such as
sub-grade fill and embankments, backfill for walls and bridge abutments, sub-grade insulation for roads,
landfill projects, and septic system drain fields. Tires are also bound together and used as different types of
barriers such as: collision reduction, erosion control, rainwater runoff, wave action that protects piers and
marshes, and sound barriers between roadways and residences.
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Artificial reefs are built using tires that are bonded together in groups, there is some controversy on how
effective tires are as an artificial reef system, an example is The Osborne Reef Project which has become an
environmental nightmare that will cost millions of dollars to rectify.
The process of stamping and cutting tires is used in some apparel products, such as sandals and as a road
sub-base, by connecting together the cut sidewalls to form a flexible net.
Shredded tires, known as Tire Derived Aggregate (TDA), have many civil engineering applications. TDA
can be used as a backfill for retaining walls, fill for landfill gas trench collection wells, backfill for roadway
landslide repair projects as well as a vibration damping material for railway lines.
Ground and crumb rubber, also known as size-reduced rubber, can be used in both paving type projects and
in moldable products. These types of paving are: Rubber Modified Asphalt (RMA), Rubber Modified
Concrete, and as a substitution for an aggregate. Examples of rubber-molded products are carpet padding
or underlay, flooring materials, dock bumpers, patio decks, railroad crossing blocks, livestock mats,
sidewalks, rubber tiles and bricks, moveable speed bumps, and curbing/edging. The rubber can be molded
with plastic for products like pallets and railroad ties. Athletic and recreational areas can also be paved with
the shock absorbing rubber-molded material. Rubber from tires is sometimes ground into medium-sized
chunks and used as rubber mulch. Rubber crumb can also be used as an infill, alone or blended with coarse
sand, as in infill for grass-like synthetic turf products such as FieldTurf.
ENVIROMENTAL CONCERNS
Due to their heavy metal and other pollutant content, tires pose a risk for the (leaching) of toxins into the
groundwater when placed in wet soils. Research has shown that very little leaching occurs when shredded tires
are used as light fill material; however, limitations have been put on use of this material; each site should be
individually assessed determining if this product is appropriate for given conditions.
FLY ASH BRICKS
The Fly Ash Bricks are promoted as an alternative to burnt clay bricks with in the construction sector in India .
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Fly-Ash Bricks are an environment friendly cost saving building product. These bricks are three times stronger
than conventional bricks with consistent strength. These bricks are ideally suited for internal, external, load
bearing and non-load bearing walls. These Bricks with higher strength/weight ratio (about 3 to 4 times that of
burnt clay bricks) aid in designing stronger, yet more economic structures.
Fly Ash Bricks are Durable, have Low water absorption, Less consumption of mortar, Economical & eco-
friendly, Low energy consumption and No emission of green house gases. These bricks are not affected by
environmental conditions and remain static thus ensuring longer life of the building. Also, the savings with
regard to wastages in fly ash bricks are considerable during unloading and construction due to true shape and
size, consistency in quality, and the workability of the fly ash bricks unlike traditional clay bricks. These bricks
are very economical / cost effective, nil wastage while transporting and handling.
THE RAW MATERIALS
The raw materials for fly ash Acc Blocks are:
Material Mass
Fly Ash 45%
Sand/Stone Dust 40%
Lime 10
Gypsum 5%
Fly ash bricks are lighter than clay bricks.
AAC (Autoclaved Aerated Concrete) was invented in the mid-1920s by the Swedish architect and inventor
Johan Axel Eriksson. AAC is one of the major achievements of the 20th century in the field of construction. It
is a lightweight, precast building material that simultaneously provides structure, insulation, and fire and mold
resistance. AAC Blocks is a unique and excellent type of building materials due to its superb heat, fire and
sound resistance. AAC block is lightweight and offers ultimate workability, flexibility and durability.
Main ingredients include fly ash, water, quicklime, cement, aluminum powder and gypsum. The block hardness
is being achieved by cement strength, and instant curing mechanism by autoclaving. Gypsum acts as a long
term strength gainer. The chemical reaction due to the aluminum paste provides AAC its distinct porous
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structure, lightness, and insulation properties, completely different compared to other lightweight concrete
materials. The finished product is a 2.5 times lighter Block compared to conventional Bricks, while providing
the similar strengths. The specific gravity stays around 0.6 to 0.65. This is one single most USP of the AAC
blocks, because by using these blocks in structural buildings, the builder saves around 30 to 35 % of structural
steel, and concrete, as these blocks reduce the dead load on the building significantly.
How to Make Fly Ash Bricks
Most modern common bricks use a mixture of clay, sand, water and lime. This mixture is pressed into molds
and then heated, or fired in a kiln at very hot (1000+ degree C) temperatures.
Fly ash bricks replace the clay with fly ash, and some manufacturing processes use pressure instead of heat to
cure the bricks, reducing the amount of energy required to manufacture.
Fly ash has been used for years around in the world in bricks. In fact, volcano ash (very similar to coal fly ash)
had been successfully used in the production of bricks all the way back in the Roman ages.
As long as the fly ash brick is manufactured to and passes the same testing standards as modern clay bricks used
in structures (ASTM C62), I dont see any drawbacks to using fly ash bricks in facility construction.
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FLY ASH BRICKS MACHIE
Quality of fly ash bricks depends on 3 factors
Input material and ratio of mixing
Process of compaction and machinery
Training of personnel to ensure consistency
Brick moulds are available in the following sizes
Size 250 X 120 x 75 mm Standard
Size 230 x 110 x 75 mm Standard
Size 230 x 110 x 75 mm Chamfered
Size 200 x 100 x 100 mm Standard
Is Fly Ash Safe?
There is currently a debate in the green building community on just how safe fly ash bricks are, since fly ash is
composed of chemicals that are considered toxic, including arsenic, lead, mercury, barium, boron, selenium,
chromium and others.However, many of these elements (in these concentrations) are found in regular
unpolluted soil, so it is difficult to say exactly how safe or unsafe they are when used in fly ash bricks.
Fly Ash Bricks and LEED
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There is a specific benefit to using fly ash bricks for green building and LEED projects because they are
considered a recycled material. This will help earn points in Materials & Resources (MR) Credit 4, Recycled
Materials.
Using fly ash bricks also reduces the amount of energy used to produce regular clay bricks, and the reduction of
CO2 emissions due to the energy intensive process to produce those bricks in a 1000 degree C kiln.
Other benefits include the reduction of fly ash waste going to landfills or being stored in a retention pond, which
can be hazardous and potentially dangerous.
All in all, I think that the direct and indirect benefits of using fly ash bricks outweigh the potential
consequences, and that their use will help a construction project to be more sustainable.
ADVANTAGES
1. High Fire Insulation
2. Due to high strength, practically no breakage during transport and use.
3. Due to uniform size of bricks mortar required for joints and plaster reduces almost by 50%.
4. Due to lower water penetration seepage of water through bricks is considerably reduced.
5. Gypsum plaster (plaster of Paris) can be directly applied on these bricks without a backing coat of lime
plaster.
6. These bricks do not require soaking in water for 24 hours. Sprinkling of water before use is enough.
DISADVANTAGES
1. Mechanical strength is weak. But this can be rectified by adding marble waste, or Mortar between
blocks.
2. Limitation of size. Only modular size can be produced. Large size will have more breakages.
The basic chemistry and technology based on which FLY-ASH Bricks is manufactured has been
successfully applied in major construction project across the globe , namely:-
a) Akashi Kaikyo Bridge Japan
b) Hungry House Dam USA
c) Euro Tunnel United Kingdom/ France
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QUALITY OF FLY ASH BRICKS
1. FLY-ASH Bricks are eco friendly as it protects environment though Conservation of top soil and
utilization of waste products of coal or lignite based Thermal Power Plants.
2. It plays a vital role in the abetment of carbon-die-oxide a harmful green house gas mass emission of
which is threatening to throw the earths atmosphere out of balance.
3. It is three times stronger then the conventional burnt clay bricks.
4. Its size of 250 x120 x 75 mm is derived from the modular concept giving perfect finish to both faces,
whereby up to 30%cement mortar can be saved during laying and plastering thus reducing the cost
of construction.
5. As no clay is used in the manufacture of FLY-ASH Bricks the scope of efflorescence is negligible.
6. It continues gaining strength on watering ever after installation.
7. Loss-due to breakage under standard working condition is less then one percent.
8. Use of FLY-ash Bricks results in 100RFT -8.33sq ft each side, which enhances valuation of built up
property.
9. Fly-Ash Bricks is lighter than the conventional clay bricks as it weight around 3 to 3.2 Kgs per
bricks.
Comparison between Clay brick and Fly ash Brick
Fly Ash Brick Clay Brick
Uniform pleasing colour like cement Varying colour as per soil
Uniform in shape and smooth in finish Uneven shape as hand made
Dense composition Lightly bonded
No plastering required Plastering required
Lighter in weight Heavier in weight
Compressive strength is around 100 Kg/Cm2 Compressive strength is around 35 Kg/Cm2
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Less porous More porous
Thermal conductivity
0.90-1.05 W/m2 C
Thermal conductivity
1.25 1.35 W/m2 C
Water absorption 6-12% Water absorption 20-25%
Present Scenario On Fly Ash In India
Over 75% of the total installed power generation is coal-based
230 - 250 million MT coal is being used every year
High ash contents varying from 30 to 50%
More than 110 million MT of ash generated every year
Ash generation likely to reach 170 million MT by 2010
Presently 65,000 acres of land occupied by ash ponds
Presently as per the Ministry Of Environment & Forest Figures, 30% of Ash Is being used in Fillings,
embankments, construction, block & tiles, etc.
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Building made of fly ash bricks
BAMBOO
When youre considering potential building materials for home construction as a society we tend to focus on
two or three commonly utilized and widely accepted building materials: wood, stone or concrete. What you may
not realize is that bamboo solutions can be used for much more than just food, musical instruments, medicine,
paper and textiles. Uses for bamboo can also include building construction, both in exterior and interior design
elements.
Widely used in Asian, Pacific Islander and Central and Southern American cultures, bamboo is a sustainable
and sturdy building material. Unlike wood, bamboo (a member of the grass family) regenerates very quickly. It
is, in-fact, one of the fastest growing plants in the world, with the fastest growth rate reaching 100cm in a 24-hr
period1.
In contrast to tree harvesting, there is simply no comparison to the replenishment rate of growing bamboo.
Bamboo can be harvested every three to six years for construction purposes (depending on the species); whereas
trees range from 25 years (for softwoods) to 50 years (for hardwoods). It is important to harvest the bamboo at
the right time to maximize strength and minimize damage brought on by pests.
Making more use of bamboo for common building practices would allow forests to regenerate and help to
prevent future deforestation efforts.
Bamboo is a very fast growing, renewable and easy-to-grow resource. There are over 1000 species of bamboo.
Bamboo grows in tropical and temperate environments and is very hardy, not needing pesticides or herbicides
to grow well. It is a type of grass and grows from it's roots, when it is cut it quickly grows back. Most species
mature in 4-5 years. It sequesters carbon dioxide and is carbon