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Using blower door with infrared


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come on guys, a building under negative pressure will increase air infiltrations thus making them much easier to observe when they might not be under equal pressure. Same for the outside scan, a building overpressurized will also make it easier to observe air leakage. When it comes to building envelopes, air can come in from one end and exit the other, that's where the blower door comes in handy.

I just want to know from those who are using it. Would it be worth investing another 3 grand plus formation to help with infrared sweeps without going into infiltrometric analysis.

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I do blower door leakage tests in south Texas in the summer. I have used my IR camera during the test. Its benefit is that with the IR camera it does highlight the hot air that is being pulled into the inetrior through leakage holes. Would I buy an iR camera just for this purpose? No! I would only buy an IR camera if I was willing to get proper training and I had some valid uses for it.

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"Worth it" is the big question. A blower will set you back a few grand; you can probably pick one up cheaper because most of the folks that thought there was a huge new business in blower door testing are unloading them for a lot less than they paid for them.

Blower doors are a quality assurance thing, not a quality control thing. There's a difference. If you're trying to figure out what to do, it could help, but it's one tool of many. If you're trying to figure out if the things done were done correctly or adequately, it's not necessarily the right tool.

It would help you find air leaks, no question. Then again, it's not hard to figure out air leaks if you've got a decent delta T. If air sealing and energy efficiency consulting is business avenue you're interested in, you would find it useful. Using it for calculating things like combustion air and ventilation calculations gets a little overly technical, and possibly very wrong.

Read this for some background.

My experience with energy efficiency stuff back in the early 80's and then again in the 2007-2012 time frame tells me everyone is very interested in energy efficiency improvements until you tell them what it will cost to implement. Air sealing is about as far as anyone will go, and even that gets them upset. You can figure out air sealing (more or less) just by walking around a house and looking.

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I have both, and several BPI certs. I never try and group the energy side with the inspection. The cold truth is just about every house stinks on the energy side of it. No one in these parts even makes a half-ass attempt to air seal, insulation in attics are 6-8", etc...

If people actually understood what a difference it makes, they'd jump all over it. I went nuts on my house last year, and cut my bills by nearly 35%. I was cash flow positive in 8 months. This past summer, when it was crazy hot, I could make my house as cool as I want. 65 felt nice when it was 100 outside.

I tell my people if you buy the house, call me back and we'll do a full audit (which can take 2-3 hours in itself). I may talk about the high points during the inspection, but nothing in the report.

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I do blower door/IR inspections often. IMO it's the fastest way to definitively identify the air leakage issues and write a scope of work for someone to fix them. Yes, you can do it without the IR part, but it will be slow if the building is at all complicated, there are high ceilings, etc., and you will probably miss stuff. You can do a fair amount of it without the blower door, too, but frankly, if your business is to find, describe, and possibly fix this stuff, why bother doing it without precision tools. I don't want to miss anything, and I don't want to be there all day. Set-up and execution are quick and the fees pay for the equipment, or else your business plan didn't work.

This is not a home inspection thing, although I think it would be a great adjunct for home inspectors (Kurt's correct comments about getting buy-in from the customer notwithstanding). I tend to get calls from people who know they need something done (they have comfort issues, often severe) so the buy-in is already there. We have mandatory blower door testing on new homes, so in those cases I am usually giving the builder a brief report on what they can improve. In other cases I am the contractor and we apply a certain amount of energy improvement stuff on just about every job.

You can also do a lot with a blower door and a home-made spray rack if you want to find water leaks.

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If you're in a market with a high awareness of energy issues, it could/would be a good long term business option. Get a cheap one second hand, and a basic IR camera; the IR comes in handy for a lot of things, and it impresses the hell out of customers. Never underestimate the value of good theater.

In my market, no one cares about energy; they just turn up the Tstat.

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with windchill in the 40 below like we've had all week, every little infiltration adds up. I might be interrested in a second hand blower door to help me with IR sweeps but havn't made up my mind yet? I like the inputs you all bring in though.

While not my main source of biz, learning the basics of BS does make you a better inspector. Get yourself a little training on how to use the equipment, it's not as simple as running a BD, you need to know how to interpret the numbers.

I've seen used systems (no IR) go for $2000 depending on how "used" they are.

A monkey could work the cam while running the BD. Stuff lights up like a Xmas tree. Not hard to find a air leak at 20MPH when you have a 50 degree temp swing. It's literally black and white on the screen.

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