Your House as a Healthy System Bruce Stahlberg

Improvements / Remodeling When one has finished building one's house, one suddenly realizes that in the process one has learned something that one really needed to know in the worst way - before one began. -Friedrich Nietzsche

Remodeling Who in the room has had a remodeling project done in the past? Who is planning to have one done?

Common types of remodels? Bathroom Kitchen Addition Basement Entire House

Common changes included Increased mechanical ventilation New heating and air conditioning system New windows, doors More insulation Air sealing / Reduction in Infiltration New roof and siding Other…

The House as a System: One improvement on your home may affect the operation of another part of your home...and not always positively. Questions to ask before remodeling!

PRE-Remodel: Questions Is the house safe? Are there carbon monoxide sources? Does it have any pre-existing conditions (that may get worse)? How tight is the house?

PRE-Remodel: Questions Are there comfort problems? Are there moisture problems? Ice dams? Water damage? What is being proposed? Does it include the entire home?

The House as a System Example Install new kitchen exhaust hood What may be some unintended consequences?

Bath fan dryer Kitchen Exhaust Water heater (natural draft) Heating / Fireplace Air is pulled from the house and has to come from some place

Bath fan dryer Kitchen Exhaust Water heater (natural draft) Heating / Fireplace Air is pulled from the house and has to come from some place Negative ( - ) Pressure

House Depressurization PRE vs. POST Will appliances still vent properly?

How leaky (or tight) is the home? Blower door test PRE and POST = what impact?

Negative pressure can create backdrafting Signs of combustion gases entering the home

Carbon Monoxide? One way to determine if you have carbon monoxide

Other Sources of Carbon Monoxide Check for carbon monoxide in unlikely locations

The House as a System Example Replace old atmospheric draft, inefficient furnace with an Energy Star, sealed combustion system? What may be some unintended consequences?

The House as a System: Example Possibly moisture on the windows the next winter And / or Orphaning of the water heater and potentially back drafting of the system

Atmospheric draft vs. power vented New furnace was elimination of a small but continuous exhaust system Possibly “orphaning” the water heater Two pipe system on right does not take any air from inside the house: closed combustion

Moisture On Windows Moisture levels can go up in home Excessive moisture on windows can ruin windows and create mold

Moisture Problems Excessive moisture can also show up in the attic Important to control the relative humidity of a home Signs of moisture at attic hatch

Atmospheric draft vs. Power vented Available in Water Heaters too Much less chance of back drafting

AIR BARRIER* WITH INSULATION *Think rain coat over sweater Sealing air leaks the easiest and most cost effective yet often missed in remodeling project

We agree insulation is important

Need to make it work right

Continuous Air Barrrier ContinuousContinuous Full contact with interior air barrier (e.g., sheet rock)Full contact with interior air barrier (e.g., sheet rock) Fully enclose conditioned spaceFully enclose conditioned space Courtesy of Southface Institute

Penetrations through the air barrier Chimney and open wall.

Penetrations through the air barrier Need to be air SEALED !

2 nd Floor First Floor Thermal Bypass Solution: align insulationalign insulation add air barriersadd air barriers Open Floor Joist air leak

Longfellow Bungalow Air Leak Major air leak often overlooked and missed Holes sealed with foam, caulk, air tight materials

Penetrations through air barrier Open floors represent large leaks

Is insulation effective? How does yellow or pink fiberglass turn so dark? Answer: Air moving through it (filter)

Insulation “We already have insulation”

Insulation Needs to be installed correctly to be effective

Avoid Problems Ice dams, moisture issues

Avoid Problems Safety, carbon monoxide Interior moisture

Project / Remodeling Process Plan! Part of planning process includes testing Home Performance Test to determine pre- existing conditions Gain information, make decisions, set priorities Communication (i.e. ask questions) with all parties (contractor, owner, etc.) Site visit or questions along the way (while still in process and dusty) Test out and Verify when project is complete

Safety concerns Do not tighten a home with a safety or serious indoor air quality problem! Correct the situation before proceeding with air tightening measures

Solutions Include Air sealing and insulation Energy Efficient mechanical equipment Designed ventilation Safe operation Increased comfort More durability

Solutions! Mechanically Controlled Ventilation High Efficiency equipment

Solutions! Effective and documented air sealing

Solutions! Properly installed insulation products

Solutions! Verify with thermal imaging

Why the need to test? Examples of real life remodeling projects  $400,000 remodel, utility audit post- inspection only, payments wanted  Ice dams, owner wanted roof torn off (just needed air sealing)  Lower efficiency equipment installed, not given option or choice

Why the need to test? Test before starting Incorporate ideas into plans Check during remodel (still dusty and messy) Best not to ask for advice after-the-fact

Home Performance Testing for Existing Homes On-site evaluation of your home Safety testing Inspection of mechanical systems; Heating, Cooling, Water heating, and Ventilation systems Inspection of insulation types, levels and values for walls, attics, crawlspaces, windows, etc. Diagnostic Pressure testing: Blower door test Thermal Imaging Camera Measuring exhaust fan flow rates Documentation of recommendations for improvement

Bruce Stahlberg