Allen Residence - Building And Maintaining A More Sustainable Home

Your home is extremely air tight. The point at which Earth Advantage counsels builders to tighten up the home is when it exceeds .35 air changes per hour. This translates into approximately 1/3 of indoor air being exchanged with outdoor air hourly. Your home is at approximately .13 air changes per hour.

When a home is this air tight, we recommend ventilation to benefit both the home and the occupants. You already have ventilation, which is very good. I ran the ventilation calculation on your home, determined by ASHRAE 62.2 and came up with 68 cfm of air. This means you need 68 cubic feet of fresh air coming into your home every minute. You can check with your heating contractor to see if this is what you have.

If you are looking into saving more energy and money, you could look into a ventilation system with heat recovery. Venmar just came out with a model that hooks right to your furnace--so you have to add very little. It is called the "Enerflo." I'm told it runs $800 installed. Since it is a new product, we have not had any experience with it, but you may want to check it out. I know Roth Heating and Cooling has been working with them. Otherwise, the Energy Recovery Ventilators (ERV's) we are familiar with run about $1,200 for the unit and $1,200 for installation.

In terms of air sealing your home further, we did find some opportunities:

1. At all of your bath exhaust fans the gap between the fan housing (the metal box) and the sheet rock can be sealed with caulking or low-expanding foam.

2. You have a small amount of leakage at the can lights where they meet the sheet rock. You can seal in the same way as the fans.

3. As you know, the door from the house to the garage needs a threshold repair.

4. The majority of leakage was coming from your exhaust hood over your gas range. You had this plugged up, which is a health issue, as gas ranges produce Carbon Monoxide when they are in operation. I believe the cold air is coming in because there is a damper issue where the vent duct terminates outside the home. It is highly possible that there isn't even a damper on it, as we could see nothing opening and closing from the outside when the fan was running. You could get something very long to fish up there from the ground (tape measure) to see if you hit any thing inside the metal box. Or, if possible, get something flexible to run through the duct from the inside of the home. I also wouldn't mind coming up and doing this for you. These are new ideas our team came up with after discussing something we haven't solved.

You asked about getting the home Earth Advantage certified. I spoke with my boss, and he said this is possible. As a starting point, the U-factor of the windows must be documented, the VOC level of the paint, and insulation levels. If you have kept track of these items, then we may be in business. The cost to certify is $600. We can put the $150 you already spent towards this. If you decide to go this route, we will need to meet with you to go over all the requirements. One major requirement is doing and passing a duct test. We can do the test for you, but if it doesn't pass, you or your heating contractor will want to be ready to seal up any leaks we find.

Information provided by:

Megan Moore-Kemp, CSBA, Building Analyst
Earth Advantage, Inc.
345 SW Century Drive
Suite 20
Bend, OR 97702
p:541-550-8185
f: 541-306-3814
e: mmoorekemp@earthadvantage.org