Download - Assessing and Remediation of Moisture and Mold in Residential Housing

July 19,2003July 19,2003The Building Performance CenterThe Building Performance Center

Assessing and Remediation of Assessing and Remediation of Moisture and Mold in Moisture and Mold in Residential HousingResidential Housing


What is mold?What is mold? Biological PollutantBiological Pollutant A living organismA living organism Can grow on almost Can grow on almost

anywhere and on any anywhere and on any surfacesurface

Needs food, Needs food, temperature and temperature and moisture to growmoisture to grow


Mold or FungiMold or Fungi

Multi-cellular and unicellularMulti-cellular and unicellular Multi-cellular formed of microscopic Multi-cellular formed of microscopic

filaments called HYPHAEfilaments called HYPHAE A colony looks velvety, granular or A colony looks velvety, granular or

leatheryleathery May appear black, red, green, yellow or May appear black, red, green, yellow or

brownbrown Most common aspergillus, pennicilium, Most common aspergillus, pennicilium,

and stachybotrys.and stachybotrys.


Mold and FungiMold and Fungi

Outdoors mushrooms, puffballs, trufflesOutdoors mushrooms, puffballs, truffles During lifecycles spores are formedDuring lifecycles spores are formed Spores small, light, travel by airSpores small, light, travel by air Need food from external sourcesNeed food from external sources Water is critical to digestive processWater is critical to digestive process Volatile compounds can be released Volatile compounds can be released

called mycotoxinscalled mycotoxins


Mold and FungiMold and Fungi

Grows on organic Grows on organic materialsmaterials

Wood Wood PaperPaper FoodsFoods


Health Effects of MoldHealth Effects of Mold

AllergenicAllergenic PathogenicPathogenic ToxigenicToxigenic


Allergenic MoldsAllergenic Molds

Allergic reactions to mold are commonAllergic reactions to mold are common Inhaling or touching may cause allergic Inhaling or touching may cause allergic

reactions to sensitive individuals reactions to sensitive individuals Mold can be dead or aliveMold can be dead or alive Repeated exposure may cause sensitivityRepeated exposure may cause sensitivity Symptoms include Hay fever reaction, sneezing, Symptoms include Hay fever reaction, sneezing,

runny nose, red eyes, skin rashrunny nose, red eyes, skin rash


Pathogenic MoldsPathogenic Molds

Cause infectionsCause infections Only small group of molds associated with Only small group of molds associated with

infectionsinfections Most dangerous for immune compromised Most dangerous for immune compromised

individualsindividuals Some infections include Hypersensitivity Some infections include Hypersensitivity

Pneumonitis, HistoplasmosisPneumonitis, Histoplasmosis


Toxiogenic MoldsToxiogenic Molds

Cause diseaseCause disease Exposure thru inhalation, ingestion and Exposure thru inhalation, ingestion and

skin contactskin contact Mycotoxins Mycotoxins Some molds have been proven to cause Some molds have been proven to cause

liver damage, central nervous system liver damage, central nervous system damage damage


Building Science BasicsBuilding Science Basics

Moisture Flow ConceptsMoisture Flow Concepts Air Flow ConceptsAir Flow Concepts Indoor Air Quality ConceptsIndoor Air Quality Concepts


Liquid FlowLiquid Flow

Driven by gravity or Driven by gravity or air pressureair pressure

Examples: roof Leaks Examples: roof Leaks and plumbing leaksand plumbing leaks

The most serious The most serious threat for a homethreat for a home


Capillary FlowCapillary Flow

Liquid water creates a suction of its own as it moves Liquid water creates a suction of its own as it moves through tiny spaces within and between building through tiny spaces within and between building materialsmaterials

Examples: Capillary action can also move liquid water Examples: Capillary action can also move liquid water into a home through damp soil and a porous concrete into a home through damp soil and a porous concrete slab or stem concrete wallslab or stem concrete wall


Air MovementAir Movement

Air movement carries water vapor into and out of Air movement carries water vapor into and out of the building and it’s cavitiesthe building and it’s cavities

Example: Hot air rises through the cracks and Example: Hot air rises through the cracks and crevices in the top of the building shell taking crevices in the top of the building shell taking water vapor with it.water vapor with it.


Vapor DiffusionVapor Diffusion

Water vapor will move through solid Water vapor will move through solid objects depending on their permeance and objects depending on their permeance and vapor pressurevapor pressure

Is the the slowest form of moisture Is the the slowest form of moisture movementmovement


Moisture RulesMoisture Rules Moisture moves from Moisture moves from warmwarm toto coldcold

Moisture flows fromMoisture flows from moremore to to lessless

Moisture hitchhikes with air:Moisture hitchhikes with air:

high pressurehigh pressure to to low pressurelow pressure Gravity pulls water downGravity pulls water down Water wicks upWater wicks up

ll


Air Flow BasicsAir Flow Basics

July 7, 2003July 7, 2003 The Building Performance CenterThe Building Performance Center

Air FlowAir Flow1 Cfm out = 1 Cfm 1 Cfm out = 1 Cfm

inin


Air Flow Air Flow

High pressure flows to High pressure flows to low pressurelow pressure


Air FlowAir FlowA hole + a driving force A hole + a driving force

=Airflow=Airflow


Driving ForcesDriving ForcesNaturalNatural WindWind Stack EffectStack Effect

MechanicalMechanical Bath FansBath Fans Kitchen FansKitchen Fans DryersDryers Forced air heatingForced air heating


IAQ BasicsIAQ Basics


Most vulnerable to the effects Most vulnerable to the effects of indoor air pollutionof indoor air pollution

ElderlyElderly ChildrenChildren DisabledDisabled Immune deficient or Immune deficient or

chronically illchronically ill Pregnant Pregnant

woman/unborn childwoman/unborn child


Children the most vulnerableChildren the most vulnerable Their bodies are still developing. Their bodies are still developing. Their immune systems are still developing and may be less Their immune systems are still developing and may be less

protectiveprotective They take in more food, water and air per pound of body weight They take in more food, water and air per pound of body weight

than adultsthan adults They are smaller and therefore closer to pollutants on or near the They are smaller and therefore closer to pollutants on or near the

ground. ground. They put their hands in their mouth more than adultsThey put their hands in their mouth more than adults Early environmental insults may have a lifelong consequencesEarly environmental insults may have a lifelong consequences


Indoor Air Pollutants Indoor Air Pollutants MoistureMoisture Tobacco smoke Tobacco smoke Pressed wood furniturePressed wood furniture Carpets Carpets Moth repellentsMoth repellents InsectsInsects Dry cleaned goodsDry cleaned goods Household chemicals Household chemicals Dust mitesDust mites Pesticides Pesticides Personal care productsPersonal care products Lead based paintLead based paint Car exhaust Car exhaust Woodstove Woodstove Paint suppliesPaint supplies PetsPets PanelingPaneling CleanersCleaners RadonRadon Products of combustion Products of combustion


Seven Steps to a Healthy Seven Steps to a Healthy HomeHome

Dry and CleanDry and CleanWater, clutter and dust permit or encourage the growth of mold, insects rodents and Water, clutter and dust permit or encourage the growth of mold, insects rodents and

mites. Keeping a home dry and clean controls mold and pests.mites. Keeping a home dry and clean controls mold and pests.

Well ventilatedWell ventilatedVentilation provides a mechanism to remove contaminants.Ventilation provides a mechanism to remove contaminants.

Combustion Product FreeCombustion Product FreeCombustion products like carbon monoxide should not be present in a healthy homeCombustion products like carbon monoxide should not be present in a healthy home


Seven Steps Cont.Seven Steps Cont. Toxic Chemicals FreeToxic Chemicals FreeToxic cleaning compounds, pesticides, oil based paints and solvents can lead to poor indoor air Toxic cleaning compounds, pesticides, oil based paints and solvents can lead to poor indoor air

quality.quality.

Pest FreePest FreePests lead to allergic reactions and pests lead to pesticides. Food and water Pests lead to allergic reactions and pests lead to pesticides. Food and water

lead to pests.lead to pests.

ComfortableComfortableUncomfortable homes can make people take action that makes a home unhealthy. If Uncomfortable homes can make people take action that makes a home unhealthy. If

people can’t afford to heat their home they won’t ventilate their home.people can’t afford to heat their home they won’t ventilate their home.


Pressures

Pollutants

Pathways

People


ReviewReview

Mold spores are everywhere Mold spores are everywhere Mold needs a temperature range from 40’F to Mold needs a temperature range from 40’F to

100’F to grow100’F to grow Mold needs food to growMold needs food to grow Mold needs moisture to growMold needs moisture to grow Mold can cause moderate to severe reactionsMold can cause moderate to severe reactions Mold is a symptom of a moisture problemMold is a symptom of a moisture problem


Assessing for Mold and Assessing for Mold and Moisture ProblemsMoisture Problems

Procedures for assessmentsProcedures for assessments Guidelines for assessmentsGuidelines for assessments Tools for assessmentsTools for assessments


Procedure for Assessing Procedure for Assessing Mold and MoistureMold and Moisture

Client interviewClient interview Pollution Source SurveyPollution Source Survey Physical survey of the building Physical survey of the building


Client InterviewClient Interview

Very valuable in Very valuable in assessing a IAQ problemassessing a IAQ problem

May have a complaint May have a complaint that should be recognizedthat should be recognized

Often know a lot about Often know a lot about their hometheir home

A chance for further IAQ A chance for further IAQ educationeducation


Pollution Source SurveyPollution Source Survey

Documents existing conditionsDocuments existing conditions Can indicate possible problemsCan indicate possible problems Identifies risksIdentifies risks May help in designing solutionsMay help in designing solutions

The Building Performance CenterThe Building Performance CenterJuly 19,2003July 19,2003

Pollution source survey


Physical SurveyPhysical Survey

Survey possible moistures sources from Survey possible moistures sources from outside and documentoutside and document

ExamplesExamples


Physical SurveyPhysical Survey

Survey possible sources from inside and Survey possible sources from inside and documentdocument

ExamplesExamples


Assessment Tools and Assessment Tools and MeasurementsMeasurements

Eyes, ears, noseEyes, ears, nose Measure relative humidityMeasure relative humidity Measure building materials moisture Measure building materials moisture

contentcontent Measure surface temperaturesMeasure surface temperatures


Measuring Relative HumidityMeasuring Relative Humidity

Thermo-Hygrometer Thermo-Hygrometer homeowner modelhomeowner model

DigitalDigital $19$19


Measuring Relative HumidityMeasuring Relative Humidity

Sling PsychrometerSling Psychrometer For measuring RH For measuring RH

takes 2 minutestakes 2 minutes $35$35


Detecting Moisture Detecting Moisture

Pin testerPin tester The process requires The process requires

making holes in the making holes in the material to testedmaterial to tested

Works on wood,sheetrock Works on wood,sheetrock ,plaster, concrete,plaster, concrete

$350$350


Detecting Moisture Detecting Moisture

Non destructive testerNon destructive tester Slides across material Slides across material

to be tested without to be tested without damaging itdamaging it

$200 to $400$200 to $400


Measuring TemperatureMeasuring Temperature

Infrared PointerInfrared Pointer Measures common Measures common

surface temperaturessurface temperatures $350$350


Guidelines for Evaluating Guidelines for Evaluating Mold ContaminationMold Contamination

New York City GuidelinesNew York City Guidelines CMHC Homeowners GuideCMHC Homeowners Guide


Small AreasSmall Areas

NYC defines as 10 sq ft or less designated NYC defines as 10 sq ft or less designated LEVEL 1LEVEL 1

CMHC defines a “small area” no larger CMHC defines a “small area” no larger than one sq meter and no more than three than one sq meter and no more than three of those areasof those areas



NYC remediation conducted by trained NYC remediation conducted by trained maintenance staffmaintenance staff

Training includes clean up methods, Training includes clean up methods, personal protection and potential health personal protection and potential health hazards hazards



CMHC say homeowners can clean up with CMHC say homeowners can clean up with detergent and gloves and dust mask and detergent and gloves and dust mask and guidance from Homeowners’ Guide guidance from Homeowners’ Guide


Mid-Sized AreasMid-Sized Areas

NYC defines as 10-30 sq ft. designated as NYC defines as 10-30 sq ft. designated as LEVEL 2LEVEL 2

CMHCC considers mid sized to be more CMHCC considers mid sized to be more than three patches, each smaller than a sq than three patches, each smaller than a sq meter or there is one or more isolated meter or there is one or more isolated patches larger than a square meter but patches larger than a square meter but smaller that three sq meterssmaller that three sq meters



NYC remediation conducted by trained NYC remediation conducted by trained maintenance staffmaintenance staff

Training includes clean up methods, Training includes clean up methods, personal protection and potential health personal protection and potential health hazards hazards



CMHC recommends assessment by a CMHC recommends assessment by a professional but if proper procedures are professional but if proper procedures are followed can be cleaned up by the followed can be cleaned up by the homeownerhomeowner


Large AreasLarge Areas

NYC defines as 30-100 sq ftNYC defines as 30-100 sq ft CMHC considers an single patch greater CMHC considers an single patch greater

than sheet of plywood “extensivethan sheet of plywood “extensive


Solving ProblemsSolving Problems

Mold is the outcome of another problemMold is the outcome of another problem MOISTUREMOISTURE Solve the moisture problem and you solve Solve the moisture problem and you solve

the Mold problemthe Mold problem


Moisture SourcesMoisture Sources

InteriorInterior ExteriorExterior Quantifying Quantifying


Moisture contributions from Moisture contributions from insideinside

Respiration, perspiration Respiration, perspiration 4pints / person / day4pints / person / day



Unvented dryersUnvented dryers 5.0 pints / load5.0 pints / load



PlantsPlants .96 pints / day / 7 .96 pints / day / 7

plantsplants



CrawlspacesCrawlspaces 0 to 105 pints / day0 to 105 pints / day



FirewoodFirewood 0-5 pints / day0-5 pints / day



DishwashingDishwashing .044 / pints / day / 4 .044 / pints / day / 4

peoplepeople



Showering,bathingShowering,bathing .52 pints / 5 minutes.52 pints / 5 minutes



Floor moppingFloor mopping .03 pints / sqft.03 pints / sqft



CookingCooking .088 pints / day / 4 .088 pints / day / 4

peoplepeople



Plumbing LeaksPlumbing Leaks



Drying laundry insideDrying laundry inside 4-6 pints per load4-6 pints per load


Standing water in crawl spaceStanding water in crawl space


Moisture from Moisture from outsideoutside This can be the largest source of moisture This can be the largest source of moisture

in a housein a house Roof leaksRoof leaks Broken or disconnected gutters and Broken or disconnected gutters and

downspouts downspouts Improper site drainageImproper site drainage Broken footing drainsBroken footing drains Improperly functioning landscape irrigationImproperly functioning landscape irrigation


Roof LeaksRoof Leaks


Improper flashing detailsImproper flashing details


Site DrainageSite Drainage


Disconnected DownspoutDisconnected Downspout


Broken Footing DrainsBroken Footing Drains


Moisture Problems are eitherMoisture Problems are either

A surface temperature problem orA surface temperature problem or A vapor pressure problemA vapor pressure problem


Common Surface Common Surface Temperature ProblemsTemperature Problems

Poor air circulationPoor air circulation

1.1. ClosetsClosets

2.2. Exterior corners Exterior corners


Common Surface Common Surface Temperature ProblemsTemperature Problems

Wind washing and Low insulation levelsWind washing and Low insulation levels

1.1. Exterior wall line at ceilingExterior wall line at ceiling

2.2. Near leaky windows or doorsNear leaky windows or doors


Solving problemsSolving problems

Reduce vapor pressureReduce vapor pressure

1.1. Source controlSource control

2.2. DehumidificationDehumidification


Psychrometric BasicsPsychrometric Basics


Dry Bulb TemperatureDry Bulb Temperature

The air mixture temperature as measured The air mixture temperature as measured by an ordinary thermometerby an ordinary thermometer

It is plotted as a family of lines along the It is plotted as a family of lines along the x-axisx-axis


Absolute HumidityAbsolute Humidity

The ratio of actual amount of moisture in The ratio of actual amount of moisture in grains of water per pound of dry airgrains of water per pound of dry air

Absolute humidity ratio is plotted on the y-Absolute humidity ratio is plotted on the y-axis of the chartaxis of the chart


Relative HumidityRelative Humidity

Relative humidity is the ratio of the amount of moisture in Relative humidity is the ratio of the amount of moisture in the air compared to the maximum amount of moisture the air compared to the maximum amount of moisture the air could contain at the same temperature and the air could contain at the same temperature and pressure.pressure.

It is a family of curved lines that slope upward from left to It is a family of curved lines that slope upward from left to rightright

100 % relative humidity line is called the saturation curve 100 % relative humidity line is called the saturation curve and it forms the boundary on the left side of the chartand it forms the boundary on the left side of the chart


Wet Bulb TemperatureWet Bulb Temperature

Wet bulb temperature is another measurement of the Wet bulb temperature is another measurement of the amount of moisture in the air.amount of moisture in the air.

Measured with a wetted cotton wick placed over the bulb Measured with a wetted cotton wick placed over the bulb of a thermometer.of a thermometer.

As the wick evaporates it lowers the reading on the As the wick evaporates it lowers the reading on the thermometer due to evaporative cooling.thermometer due to evaporative cooling.

The lower the amount of moisture in the air, the lower The lower the amount of moisture in the air, the lower will be the wet bulb temperature because a higher rate of will be the wet bulb temperature because a higher rate of evaporation will occur in dyer air.evaporation will occur in dyer air.

These values are shown along the saturation curve.These values are shown along the saturation curve.


Dew Point TemperatureDew Point Temperature

It is the dry bulb temperature at which It is the dry bulb temperature at which condensation first occurs as heat is condensation first occurs as heat is removed from the air.removed from the air.

The dew point is found by moving The dew point is found by moving horizontally along the chart from the given horizontally along the chart from the given point to the saturation curve.point to the saturation curve.


EnthalpyEnthalpy

It is the total amount of heat contained in It is the total amount of heat contained in the air mixturethe air mixture

Enthalpy is plotted as a family of diagonal Enthalpy is plotted as a family of diagonal lines on the chart that slope upward from lines on the chart that slope upward from right to left.right to left.


Specific VolumeSpecific Volume

Is a measurement of the volume occupied by the Is a measurement of the volume occupied by the air based on it’s weight.air based on it’s weight.

It’s measured in terms of cubic feet per one It’s measured in terms of cubic feet per one pound of dry air.pound of dry air.

Specific volume is is plotted as a family of Specific volume is is plotted as a family of diagonal lines that slope sharply upward right to diagonal lines that slope sharply upward right to left.left.


Psychrometrics Exercise #1Psychrometrics Exercise #1


Mold and RotMold and Rot


MOLDMOLD


MoldMold


More MoldMore Mold


MoldMold

Download - Assessing and Remediation of Moisture and Mold in Residential Housing

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