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Weatherization & Indoor Air QualityImpacts of Weatherization on Air Quality and Comfort Inside Your Home

www.epa.gov/iaq/climatechange

What is Weatherization?

• Conservation activities applied to a building which help to protect the building from the elements, conserve heating or cooling energy, maintain temperature and provide a safe, comfortable, and healthy living environment.

www.epa.gov/iaq/climatechange

Typical Weatherization Components

Weatherization Assessment• Determining the condition of the

home • Energy Audit• Visual Inspection• Blower Door / Duct test• Other Diagnostics

Weatherization Retrofits• Building Envelope– Sealing/Tightening– Windows & Doors• Insulation• HVAC – Heating, Cooling,

Ducts• Designed Ventilation• EE Upgrades (Appliances)

Weatherization Plan• Prioritized• Customized

www.epa.gov/iaq/climatechange

The House as a “Living System”

• Comfort• Health• Safety

• Durability• Sustainability

Changes made as part of a weatherization plan can impact more than energy efficiency.

A Holistic approach to renovations will also address:

www.epa.gov/iaq/climatechange

Healthy Indoor Environment Protocols

• Building Systems– HVAC– Combustion Safety– Source Ventilation– Whole House ventilation– Multi Family Ventilation

Organized by Priority Issues – Alerts auditor, planner and contractor to to potential issues; recommends minimum and expanded actions

http://www.epa.gov/iaq/homes/retrofits.html

• Contaminants– Moisture

– Radon

– Wood Smoke

– CO, NOx, etc

– Lead

– Pests

– Building Products

– Asbestos

– Other

www.epa.gov/iaq/climatechange

Weatherization AssessmentWhat’s Done?

• Energy Audit– Energy performance– Base Loads• Visual inspection– Overall condition– Visual clues• Thermal Imaging• Blower door Test– Amount and distribution of leakage• Duct test– Loss of conditioned air• Other Diagnostics & Tests– Backdraft, CO2,RH,

Purpose:• Determine Baseline• Determine Options• Identify IAQ Concerns

http://www.waptac.org/Weatherization-Assistant/Weatherization-Assistant-8002E5.aspx

www.epa.gov/iaq/climatechange

www.epa.gov/iaq/climatechange

Weatherization PlanWhat improvements will be performed

Approach• Prioritized– Health – Cost Effectiveness

• Customized – Test results– Building Specific– Occupancy & Operation

Considerations• Safety• Energy• Indoor Air Quality• Comfort• Cost Effectiveness• Sustainability

www.epa.gov/iaq/climatechange

Weatherization RetrofitsHow can changes impact Indoor Air?

• Temperature Differentials –

– Condensation

– Air Flow

• Pressure Differentials –

– Air Flow

• Moisture Management –

– Humidity

• Air Sources, Volume, Movement (Ventilation)

• Pollutant Sources & Controls

www.epa.gov/iaq/climatechange

Building EnvelopeSealing, Tightening, Windows & Doors

Weatherization Action• Blower Door / Duct Test based• Reduce air leakage, resistance to

heat transfer, thermal losses/gains• Size and distribution of uncontrolled

airflow

Impact on IAQ• Stack Effect / • Source of Leakage Air• Radon• Reduced “Natural” Ventilation– Less fresh air for occupants– Increased Humidity– Increased Pollutant Levels

(indoor sources)– Increased Odors• Spillage / Backdrafting

www.epa.gov/iaq/climatechange

Insulation

Weatherization Action• Resistance to heat transfer,

thermal losses/gains

Impact on IAQ• Moves dew point surface –

Shifts condensation to exterior wall

• VOC – type of insulation• Loss of containment - Fibers

/ Particulates• Decreased Air Movement

www.epa.gov/iaq/climatechange

Heating /Cooling / HVACWeatherization Action• Programmable Thermostat• Ducts– Replacement– Sealing– Balancing

• Furnace or A/C changeout– Efficiency– Right sizing– Combustion Venting– Fuel type

• Wood stove changeout• Ventilation

Impact on IAQ• Alter Pressure balance• Combustion makeup air• Spillage/Backdrafting• Emissions• Humidity

www.epa.gov/iaq/climatechange

Designed Ventilation / Radon Ensuring Adequate Ventilation

Weatherization Action• Minimum Ventilation Rate– Blower Door data based– Sized for occupancy– Volume– Natural ventilation

• Designed Fresh Air• Heat Exchangers• Exhaust fans• Active Radon Control

Impact on IAQ• Humidity• Odors• Comfort• Radon• Point Sources

www.epa.gov/iaq/climatechange

Energy Efficient Upgrades

Weatherization Action• EE Lighting• Hot water– Replacement H2O heater– Insulation– Reduce demand (lo flow)

• Fans (attic, ceiling)• Appliances

• PV/Wind

Impact on IAQ• Air movement• Mixing• Emissions • Humidity

www.epa.gov/iaq/climatechange

Holistic Considerations

• Landscaping shading

• Water conservation

www.epa.gov/iaq/climatechange

Homeowner / Resident EducationHow to Effectively Operate and Maintain the Renovated

House

• Energy conservation• Ventilation• Humidity • Sources • Lifestyle

• Maintenance

• Routine

• Scheduled

• In response to observations

– Don’t ignore changes that you observe – “Listen” to what your body & family are telling you

www.epa.gov/iaq/climatechange

Additional Resources• EPA’s Indoor Air Quality Web site:www.epa.gov/iaq

• Climate Change: www.epa.gov/climatechange/

• The Inside Story: A Guide to Indoor Air Quality: www.epa.gov/iaq/pubs/insidest.html#Intro

• ENERGY STAR Home Improvement:www.energystar.gov/homeimprovement

• Mold and Moisture:www.epa.gov/mold

• Weatherization Assistance Program Technical Assistance Center (WAPTAC)

http://www.waptac.org/