Quote:
Originally Posted by holliswuzamember
okay, I think I did a pretty good job of air sealing my house. We do this to all of our apartments as tenants move out and it has really helped with heating bills both on the apartments and my house.
We use a number of things,.. an infrared camera, and a blower door are the two best things. Actually we seldom use a blower door anymore but put a high-capacity fan in one window set back about a foot and 1/2..Blowing out on the first floor. Closing everything up including (temporarily and label the on/off switch to remember to clear them before they are switched back on) each stacks for the furnace and hot water. We then turn on the fan and if you stand outside, you feel the huge amount of air rushing out that you have to heat. There is a lot of pressure for cold air to push in and that air is coming in just as fast on a very cold day.
Then you can go inside and use a moist hand /the infrared camera, or a piece of smoky incense and find any leaks. At first some of them are pretty big. We usually close all the interior doors and pop one open at a time to find which are the leakiest rooms. Then we spend time for the worst ones first.
Does it make a difference? Yeah sure does ,..we spend less on heating bills then we used to. Also on those very windy days we feel no drafts in the house. Our tenants also are happy with their heating bills and no drafts.
Can you overdo it? I suppose you can on maybe newer houses but we have not found that to be a problem yet. After we do our sealing you can go outside and turn on that big fan again and note considerably less air coming out of the house. With Someone in the house, have them raise a single window and you can feel the big blast returning.
I think an older house it's very, very hard to over seal it. Point in fact today it is relatively cold out. So there's a lot of pressure of cold air trying to push into the house. We don't feel it now so so that's nice. However a car obviously hit a skunk on the road near the house, and it didn't take that long to really smell it in the house, showing that that air is leaking in more and faster than one might would think.some engineering studies say the average house has a 3x3 window MORE THAN YOU NEED for good ventilation open 24x7,.,.Try heating your house with a 3X3 window open 24x7,..
Anyway I'm thinking of doing it again seeing if I can find a few more. I remember reading an engineering book that the average house has a complete air exchange 5 to 9 times and hour! The reason why you don't feel that it's 10 degrees from that outside air coming into your 72° house is that the mass in your house retains enough heat and will not drop it down very fast. But its still using a lot of energy to keep it up.
|
Air sealing is a good thing, but for every action, there is a equal reaction. You can have a house that everything is functioning in and air seal it and now the dryer will backdraft the furnace, or the range vent will backdraft the water heater. You shouldnt address air sealing without addressing mechanical ventilation. Back when we were doing research for the NAHB, we used to get really, really anal about air tighness. I think our lowest ever was like .23 ACH/Hr @50pa.