Why can’t chemical smoke pass out of the building envelope when pressurized?
Instead of blowing away from an opening, it will get sucked in.
I am in favor of sucking over blowing, but it can be done.
It may have to be done at a higher pressure (60 vs 20 pascal), but it can be done.
I have seen it done with a smoke pen. It is pretty freaky to see smoke draw out of house.
Well, gentlemen, the smoke pencil is a chemical, and I don’t use chemicals. The back of my hand works equally well but only during the de-pressurization test.
How much smoke do you use? Not trying to be funny. But in the big scheme of things…it can’t be any worse than when I pass gas. If I had to compare the two, I think people would rather have the smoke than my gas.
You could use one of those theatrical foggers also.
Or as a last resort I could stand on one side of the wall and pass my gas and you on the other to sniff it out. LOL :D. Sorry I couldn’t resist that one.
Mic
There is about as much smoke from a smoke pencil as there from a cigarette. Pressurization works fine, depressurization is a bit easier thats all. Its not like the h/o is in contact with the smoke, the air pushes/pulls it outside the home in a matter of seconds.
Not accurate!!
You can use a blower door to “pressurize” the building and then use an Infrared Camera to detect air exfiltration on the exterior envelope. This survey is usually conducted a night or two hours post sunset.
Remember that due to the principles of “stack effect”, air infiltrates in the lower plane of a building, while air exfiltrates in the upper plane of a building.
However, I’ve never really found the need to use a blower door, and I’ve conducted hundreds of energy audits using ITI. When I first started doing them with infrared, I would conduct them during normal business hours (daytime), but I have since changed that and conduct all of my energy audits at night. That way I can detect both air infiltration/exfiltration by conducting interior/exterior scans. Plus, in my area (wash DC) you get a way better temperature differential at night.
Kevin
The best place to reduce air leakage is at the interior wall surfaces of the outside walls, therefore, the best way of finding air leaks is with depressurization of the building on cold days. The quickest way to find the air leakage would be with IR while the building is depressurized.
When you see air leakage on the outside of a building, you may not find the exact location of the air leakage at the inside wall surface, that’s where you want to seal it. It’s similar to finding a roof leak sometimes… where the water shows up on the ceiling may be many feet away from the actual roof leak!!
Agreed! The best and probably the easiest way to detect air leakage is from within the building. That is not to say that it cannot be done from the exterior. An exterior IR scan is a lot more difficult and has a lot of factors that can produce errors or misleading conclusions. Just because it’s not consider “easy” does not mean it should not be done.
Proper training and experience is critical for conducting exterior energy loss scans using infrared (with or without the blower door).
Kevin
Oh yea of little training…
Care to expound on your theories…or deeper knowledge??
I’ve received requests for blower door IR scans and I simply tell the callers that blower door scanning simply magnifies anomalies that my camera can detect anyways. I still book the IR scan.
I would like to purchase blower door equipment, but the problem I’m having now is finding someone to train me on how to properly set it up and read the instrumentation. I’ve contacted locals here but they refuse to return my calls because they’re afraid I’m going to cut into their side of the business.
If someone can show me how to properly utilize the blower door system, I’m interested in getting together.
David,
If you purchase a Minneapolis Blower door system it comes with in depth instructions on how to set-up and operate.
Great. I like the fact that the directions come with the product, but I would like to obtain hands-on training, in order for me to know exactly what I’m doing when performing these BD tests for the first couple of times.
I don’t think anyone (new at BD testing) would feel comfortable performing a blower door test for the first time and reading the directions while setting it up. The clients would love to see the professional they hired reading the directions, ayyy?
That’s why I prefer to participate in a hands-on training.
If anyone (with a BD) wants to volunteer their time, I’d have no problem flying out to you.
David:
Why not fly out to the Energy Conservatory or Retrotec and pick up your door. They’ll probably be more than willing to instruct you!
Energy Conservatory](http://www.energyconservatory.com/)
www.energy****conservatory.com
2801 21st Ave S # 160
Minneapolis, MN
55407
(612) 827-1117
PS: There is an additional use for a blower door that no one has mentioned yet:** Enclosure Integrity Testing** to NFPA 2001. Being in a highly populated area, there may be a way to work into that market. I did a couple of tests before I got out of the private contractor market in 1990. Both were for an electrical utility: One was on a 25 megawatt electrical generation backup station (using a modified 747 jet turbine) and the other was for the central communications facility at head office.
http://www.energyconservatory.com/applications/applications6.htm
http://www.retrotec.com/fire_testing/
Current president of Retrotec, Colin Genge, wrote the original 2001 standard and should still be one of the best sources of info on the topic. Met him when bought my door in 1981. He’s very approachable and willing to talk.
I’m looking into training (on the instrumentation) as we speak.
Thanks.
I have spoken to several professionals that provide energy inspections and use blower doors in my area.
The normal fee is $350. One company is offering an energy inspection for $149.
I am having them come do my home. I figure for $150 I can watch an expert and ask him a lot of questions and also see where I am losing energy. (I know were my heat losses are I just want to see how the camera and blower door work)
I want to see the blower door and thermal camera they use.
Look into the Duct Blaster unit. You can use it for duct leak detections and also use it as a blower door fan. I have been looking into the equipment myself too.
Scott,
I don’t think you can use the duct blaster system as a blower door. It is a much smaller fan and a different setup. It wouldn’t come with a door frame.
According to the website and product literature you can use it as a blower door fan. It won’t handle huge houses, but for the average home it says it will do just fine. There is a door frame for it that you can buy separately that fits the fan.
Good point, Dave. I may do the same if I must.
