status and opportunities of promoting bamboo and hollow concrete block as low carbon construction...
DESCRIPTION
Presentation made by Suman Udas from Clean Energy Nepal at the "Low Carbon Options in South Asia" workshop held in Nepal in August 2014.TRANSCRIPT
Status and Opportunities of Promoting Bamboo and Hollow Concrete Block as Low Carbon
Construction Material
Suman UdasClean Energy Nepal
Existing Housing Scenario in Nepal
2001/2002 2011/20120
1,000,000
2,000,000
3,000,000
4,000,000
5,000,000
6,000,000
4,253,220
5,427,302
Num
ber o
f hou
ses
27.6% increase in houses
There will be an additional need of 1 million urban houses from 2011-21 (UN-Habitat, 2011).
Household by type of foundation
44.2%
17.6%9.9%
24.9%
2.3% 1.1%
Mud bonded bricks/stone
Cement bonded bricks/stone
RCC with pillar
Wooden pillar
Others
Not Stated
Source: CBS(2012)
Household by type of walling material
41.4%
28.7%
5.3%
20.2%1.1% 2.1% 1.1%
Mud bonded bricks/ stoneCement bonded bricks/stoneWood/planksBamboounbaked brickothersunstated
Source: CBS(2012)
Existing Housing Scenario in Nepal
• Traditional houses with mud and stone were common in the past
• Traditional houses were designed to suit local climate using indigenous knowledge and locally available materials like soil, stone, timber, bamboo and woods.
• Traditional buildings has decreased dramatically during past six decades
• Use of contemporary material like cement, brick, concrete, steel and aluminum for RCC frame building has increased.
Existing Housing Scenario in Nepal
• 700 brick kilns in Nepal of which 120 are operating in the Kathmandu valley itself (ICIMOD, 2014). The capacities of these kilns range from 15,000 to 50,000 bricks per day.
• Kathmandu Valley is losing at least 217,000 cubic meter of top fertile soil due to uncontrolled excavation to produce 117 million bricks per year.
• Nepal consumes 350,000 tons of steel rods per year.
• Nepal at present consumes around 2,500,000 MT of cement. Cement sales have been increased by 10% annually in 2013. (Nepal Cement Manufacturer’s Association, 2013)
• Domestic cement production fulfills 75% of total consumption in Nepal (Nepal Cement Manufacturer’s Association, 2014). The remaining demand is met by imports from India.
Use of Bamboo in Housing and Building
ConstructionBamboo - A material for cost effective and energy efficient building
construction
Traditional Bamboo Uses in Nepal
Worldwide bamboo is used 1500 ways and in Nepal it is reported to be used 294 ways
Major Uses of Bamboo in Construction
• Scaffolding
• Reinforcement
• Roofing
• Walling
• Doors & Windows Source: Abari
Source: http://www.travel-images.com
Source: http://thenepalproject.org/
Opportunities of Bamboo Housing
• Bamboo processing and production consumes less energy compared to other building materials. It requires only 30 MJ/m3 compared to concrete, steel and timber, that require 240, 500 and 80 MJ/m3 respectively.
• Bamboo houses are environment friendly and have better earthquakes resistance
• There is a great opportunity to promote bamboo for the construction of houses by converting or processing bamboo into engineered panels. Existing value added market for the panel based (engineered) bamboo housing is almost none in Nepal providing great opportunity to explore this market.
• Bamboo houses would contribute to the society by providing affordable but quality prefabricated bamboo houses to poor and homeless people.
Bamboo Resources in Nepal
• In Nepal, 12 genera and more than 50 species of bamboo have been recorded so far (TIS, 2004).
• Nepal has 5 genera and 27 species under large bamboo species which are commonly called Bans in local language and come in Bambusae tribe. Small bamboos include 15 genera and 35 species. On the other hand 3 genera and 4 species fall under dwarf bamboo species.
• The total bamboo coverage area in Nepal is estimated to be around 63,000 hectares, out of which 60 percent is estimated to be in natural forests.
Bamboo Resources in Nepal
• Estimated total growing stock is around 15 million cubic metre with an approximate biomass value of 1060 M. tons (Karki and Karki, 1995)
• About 3.3 million farming families are estimated to be somehow involved either as producers or users of bamboo based products (Pant 2006).
Market Annual Trade of BambooLocal Market 1.9 million culmsDomestic Market 0.6 – 0.7 million culmsIndia 0.5 million culms
Bamboo based economy only contributes 1-2% to the national GDP. (Karki et. at 1998)
Area of Bamboo Agricultural Land
1991/1992 2001/2002 2011/20120
1000
2000
3000
4000
5000
6000
7000
8000 6000 63007230
Area
(in h
ecta
res)
Source: CBS(2012)
Bamboo Agricultural Land Distribution by Region
Eastern Central Western Mid-western Far-western 0
500
1000
1500
2000
2500
3000
3500
3100
2300
700
200
Area
(in h
ecta
res)
Source: CBS(2012)
Samata Sikshya Niketan (Bamboo Schools)
Samata Sikshya Niketan is a privately managed community school which provides education up to higher secondary (Grade 12) in only NRs. 100 per month.
19 different schools around the country so far and interesting thing about this school is that all the school building, compounds and furniture are made from bamboo.
source: http://nepalesechildren.blogspot.com/
source: http://fr.ulule.com/
Habitat for Humanity Bamboo Houses
• Habitat for Humanity (HFH) started engineered bamboo housing for poor people to uplift the living standards of the rural poor in eastern districts of Nepal
• The houses constructed are one storied with the use of wood, bamboo, concrete, bricks, Corrugated Galvanized Iron (CGI) roofing sheets and mud tiles.
280 Sq.ft house, Stone foundation, Bamboo wall plastered with cement(Source: Habitat For Humanity)
280 Sq.ft. house, stone foundation, Bamboo wall in timber frame with cement plaster and tin sheet roof (Source: Habitat for Humanity)
• HFH constructed 20,000 houses by 2012 using low cost bamboo housing techniques.
• HFH envisions to build 100,000 by 2016 using low cost and eco-friendly housing techniques such as bamboo.
Challenges Ahead
• Concept and Perception of bamboo as construction material
• Supporting Policies
• Quality assurance and aesthetic value of materials
• Technology and Research
Hollow Concrete Block - A material for cost effective and energy efficient building construction
Use of Hollow Concrete Block in Building Construction
Existing Scenario of HCB Market
• Hollow Concrete Block (HCB) is a walling material, applicable to both load bearing and framed structure buildings. In Nepal, mostly used under Load bearing system for constructing houses
• No inventory on number of HCB industries across Nepal. There are numerous formal and informal small scale enterprises producing HCB
• A mixture of cement: sand: aggregate in the proportion of 1:3:5 is usually considered suitable for constructing blocks for load bearing wall. However, in market there is no quality assurance
• HCB houses are cheaper compared to RCC buildings and are more energy efficient, however the use of these materials has not been in substantial numbers due to lack of incentives and supportive policies. (Shrestha, 2013).
Opportunities of HCB
• Brick one of the most used construction material in Nepal has a very high embodied energy level(100~170% higher than hollow concrete blocks) and to meet the need for 1 million housing, 20 billions of bricks will be needed i.e. 85,000 tera-joule energy will be needed. Hollow Concrete Block has potential to replace brick for achievement of low carbon development path
• Nepal lies in seismic zone and HCB provides opportunity to develop Earthquake resistant houses preventing disaster
• Unlike clay burnt brick, HCB does not use top fertile soil for production
• The building construction with HCB is easier and faster making construction more cost-effective. HCB houses are 30-40% cheaper compared to RCC frame building and contribute to the society by providing affordable houses to poor.
Housing for People (Janata Aawas Karyakram)
• Government initiative on low cost housing to support poor and marginalized groups in Sarlahi, Mahottari and Surkhet
• Government’s target failed due to the lack of social acceptance and public opposition.
• General impression of low cost housing for the people means low quality who are unaware of the technologies and its benefits
• People demanded government should make quality houses using the cement mortar and burnt bricks instead of HCB, soil cement blocks and bamboo
• Government was forced to construct cement brick masonry houses. The program has a target of construction some 3000 houses and about 2200 houses are already completed
HCB Housing at Sitapaila
Santosh Man Shrestha: “Many people are interested and ask about HCB housing, but most people hesitate to go for HCB house as people perceive RCC are safe compared to HCB house which are built under load bearing system.”
Bidur Pandey: “The main reason he bought the house was due to its low cost and trust in the quality of house.”
Rajesh Manandhar: “I am keen in building HCB house in near future.”
Sailesh Shrestha: “The main reason I bought this house was due to its cost which was about 4.5 million rupees including land that was almost half of the price to buy RCC house of the same size and other reason was assurance of quality of house. My neighbors and relatives generally perceive this house made of HCB to be weak but it is not so.”
Housing in Satungal
• Three HCB houses constructed in Satungal with main objective to provide house for poor people living in that area
• After the construction, in consensus with the ward office, the houses sold at NRs 0.5 million through application procedure based on the lucky draw.
• Other owner of the house bought this house for NRs 2 million from the owner who bought this house for NRs 0.5 million within a year.
• He feels cheated knowing that this house is made of HCB and cost was only NRs 0.5 million.
• Kamala Giri, bought this house for NRs 1.65 million from the owner who bought this house for NRs 0.5 million within a month of lucky draw.
• She was unaware while buying house that this house was low cost only of NRs 0.5 million made of HCB which has made her perception that the house she owns is of very low quality.
Housing in Lamatar by Bhatbhateni Group
• More than 100 houses under construction
• Of 100 houses being constructed, 70 of them are already booked.
• Each house two and a half storied with 3 rooms in each floor
• The price for a houses with area of 1324 sq. ft is NRs. 3.7 million including price of land.
• Main reason for sale of this house is because of low prices with assurance of quality and presentation of brand.
• HCB are produced on construction site and sample from production is tested for strength in Pulchowk Engineering Campus for quality control.
• Big potential of HCB housing in the future due to its cost effectiveness. Future plan to expand its market
Challenges Ahead
• Concept of Hollow Concrete Brick as an alternative to brick
• Code and Regulation
• Limited Availability and lack of information
• Quality assurance and aesthetic value
• Research
Thank You