Home energy audit

[Scott K]

I was thinking about getting a home energy audit done to see is I have any large leaky areas. But then I got to thinking, if your house is to tight, how will it breath? My house was built in the early 90's, and doesnt have an air exchanger.

My question is, is there a benefit to sealing the house up tight, then have to install an air exchanger to cycle fresh air in the house? Isnt a few leaky windows, and doors doing the same as an air exchanger? Just bringing in fresh outside un heated air? If so, then why install such tight fitted doors and windows?

I am sure there is something I am missing here, since I dont see the point of sealing all the house up tight, then adding an air exchanger to bring in fresh air, which is what the leaky doors and windows were doing for free.

[Tom7227]

I had one done a bit over a year ago. You can learn a lot about what's going on with the house. I ended up buying some clear caulk and going around the outside of the framework on the windows and some beams in the family room, putting those little foam jobberdos behind the plates for outlets. The guy set up a blower fan in a door and used a Flir that took pictures. He then took pictures with a regular camera. When I got the report it allowed me to zero in on exactly what needed to be done where.

You also get a reading on how leaky your house really is. I wish that I had recorded the numbers because the report gives a pretty simplistic graph showing that it is not leaky, needs minor work all the way to 'dude you living in a teepee?' With that knowledge you can begin to determine if an air exchanger is needed even after you take care of the minor stuff.

[delcecchi]

Air exchangers recover some of the heat from the outgoing air and use it to warm the incoming air. Leaks just let in cold air and let out warm air.

[Scott K]

Air exchangers recover some of the heat from the outgoing air and use it to warm the incoming air. Leaks just let in cold air and let out warm air.

I didnt know that.

But, financially speaking, to tighten up your not too drafty house, and then having to install an air exchanger to exchange the air, then having to run the air exchanger, would it make financial sense?

I know I have a patio door that is bad, and was planning on replacing it before winter came, but wonter snuck up on me, so I think I will wait until spring now. Then have the audit done in the spring.

[FlagsDown]

You probably won't have to worry about getting it too tight-there will be leakage areas you just can't do anything about.

The audit can help find any areas of missing or fallen batts in the walls that can lead to moisture problems.

[Tom7227]

I had it done in the winter when the temp differences were most pronounced. I don't know how sensitive the FLIR was that the man used and so maybe it wouldn't have made a difference. What I do know is that he was able to pick up on some things that were pretty subtle.

I had an area that had a vaulted ceiling that was totally uninsulated. That was my biggest problem and my son and I fixed it last year. I would bet that I didn't spend more than $75 to do all the rest that was recommended. A roll of insulation for the rim joists, a can or two of foam and about 5 tubes of clear caulk.

What was a bit irritating was that Xcel billing doesn't give you enough data to make a comparison. I asked them and eventually they sent me a spread sheet of my billing. Didn't have degree day data and was in some goofy format that required a lot of screwing around to get it into a spreadsheet. I got frustrated and gave up. Bottom line is that I don't know with any evidence that my tightening up did any good at all. I know that it had to have had some effect, but I don't know how much. Add to that the ridiculously low price of natural gas right now and it is almost impossible to rationalize doing anything from a cost/benefit standpoint.

[Tom7227]

Scott,

The answer to your question is no, you are not going to be able to cost/benefit an air exchanger from an energy savings standpoint.

First of all you simply are not going to be able to tighten your house enough to get to the point of needing one. I suppose you could if you were to totally tear it down to the studs and insulate and poly the place like they do now days.

Second, you're too old. If there were a positive economic benefit it would be so low that you'd be in the ground before it 'paid' for the exchanger.

Happy New Year!

Tom

[Scott K]

How much did you pay for the audit?

[Tom7227]

$100 scheduled through a program from xcel. Don't know that they come as far as you though.

[jps]

I was told by our utility company, coldest day of the year is best time. I suppose in Arizona it would be the hottest day. Cost is $45. This is nw Iowa. jps

[harvey lee]

I love my air exchanger if for nothing more, to set the humidity in the house.

[Tom7227]

I love my air exchanger if for nothing more, to set the humidity in the house.

Tom, do you have to reset the humidistat on the air exchanger in this cold weather? I have an Aprilaire and the instructions indicate it should be changed to deal with temp changes. Tom