housing action illinois 2009 convention

Housing Action Illinois 2009 Greening Rehab

Alex FullerCenter for Neighborhood Technology

Craig MattesonARC Insulation, Inc.

• Energy audits, construction management, low-interest loan through CIC

• Multifamily building owners in private and subsidized markets

• 260 buildings, 9,000 units audited so far

• Measure impact of energy efficiency on affordability and housing preservation

Energy Savers Program

(a)Put up a wind turbine

(b) Install photovoltaic panels

(c) Literally go green

(d)Build your own nuclear power plant

(e) Insulate and air-seal

You want to go green.The first thing you should do is

The Nightmare Scenario:

An inefficient building that you try to run on renewable energy. First make the building burn as little fossil fuel as possible. Then go after renewable/sustainable/green/ clean/eco-friendly technology.

Measuring greenResidential Energy Services Network

(RESNET)

Leadership in Energy and Environmental

Design (LEED) Energy Star

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What’s important?

Electricity

Gas

Simplified House – A box of hot air in cold air

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Conduction heat loss

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Moral of the story:• Worse than you’d think. Low R-values disproportionately

drag down the overall R-value.• Heavily insulating one side is exponentially useless.• In an ideal world, insulate all sides evenly.

Area-weighted R-values

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Convection heat loss

Air leaks in at the bottom

Air leaks out at the top

Somewhere in the middle, no air leakage

From Insulate and Weatherize by Bruce Harley:

Older homes usually had little or no insulation and were quite leaky. They are the basis for that pearl of wisdom “a house has to breathe”…One approach to dealing with this is a head-in-the-sand stance: Let’s not make this house “too efficient” in the hope that it will “breathe” and stay healthy.

Why make a house tight, and then spend money to ventilate it? Doesn’t it make more sense to just leave it a little bit leaky? The short answer is no. A leaky house experiences haphazard ventilation that may or may not be appropriate or adequate. A good ventilation system, on the other hand, allows you to control the introduction of fresh air into a home.

Air-sealing – Tedious but Important

Good books

Insulate and Weatherize by Bruce Harley

Residential Energy by Krigger and Dorsi

Mortgage Industry Nat’l Home Energy Rating Systems Standards

Where does your house fall?20

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Energy use intensity (kBTU/sq ft/yr)

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