I am not an energy Rater .. I am an architect

I am curious if any "Home Energy Pros" make an effort to locate the Neutral Pressure Plane (NPP) of a house that is being blower door tested?

Views: 2619

Reply to This

Replies to This Discussion

Don, I agree, I agree,

As for actually pointing to an elevation and saying the NPP is about here, somewhere in one of these posts I explained how to do that and it is rather easy.  All that is necessary is a ▲t and a manometer.  From inside and outside temperatures, a stack pressure per foot can be calculated.  Then, by taking a high or low pressure reading (that's where the pressure will be the largest) through the envelope, you have it.  If the front door reading is 2pa and you had calculated a 0.25pa per foot stack pressure, then the NPP is 8' above the penetration at the front door.

If you want to get fancy and you have a good ▲t, you can open a window a measured amount and, just like the "add a hole" process for pressure diagnostics, you can estimate the CFM50.  I keep baiting people with this in hopes that someone will do the math for me :).  My to-do list it too long.

As for the metal capillary tube, you can't get too small as a manometer does require a flow of air.  I would have to ask to be sure.  Just an FYI.

Bud

PS, I have started another thread to get into this issue a bit more: http://homeenergypros.lbl.gov/forum/topics/controlling-passive-air-...

RSS

Home Energy Pros

Home Energy Pros was founded by the developers of Home Energy Saver Pro (sponsored by the U.S. Department of Energy,) and brought to you in partnership with Home Energy magazine.

Latest Activity

Tom Conlon commented on Kurt Shafer's blog post What is your opinion about members promoting products here?
"I just checked the site Guidelines Kurt, and any true "promotions" should be posted in…"
17 hours ago
Tom Conlon posted a discussion

Whole House Fans - Love 'Em or Not?

I just searched this forum for "Whole House Fan", but I didn't find much about them (except …See More
18 hours ago
Richard Beyer replied to Mike Kandel's discussion Our Homes Suck – And That's Why Our Kids Have Sinus Problems
"Don, Thank you for the praise! I only wish that some of these profiteers could answer my questions…"
20 hours ago
Richard Beyer replied to Mike Kandel's discussion Our Homes Suck – And That's Why Our Kids Have Sinus Problems
"Todd, This report (attached link) below on poor people living in subsidized housing show's…"
21 hours ago
Mike Kandel added 4 discussions to the group Building Performance Institute (BPI)
22 hours ago
Mike Kandel posted discussions
22 hours ago
Nate Adams commented on Jim Gunshinan's blog post My Energy Upgrade California—The Numbers Are In
"Jim, Glad to help! OK, a touch of soap box. So long as we don't tell people EE is free and…"
23 hours ago
Kurt Shafer commented on Kurt Shafer's blog post What is your opinion about members promoting products here?
"Bob, Good idea. I see that you are a window energy reduction expert. You might consider adding…"
yesterday
Robert (Bob) Bacon commented on Kurt Shafer's blog post What is your opinion about members promoting products here?
"Kurt, I would explain what energy/efficiency problem this device solves and explain the science the…"
yesterday
Ben Jacobs replied to Mike Kandel's discussion Our Homes Suck – And That's Why Our Kids Have Sinus Problems
"I agree that in many homes the indoor air sucks.  However, a lot of this problem is caused…"
yesterday
Kurt Shafer commented on Kurt Shafer's blog post What is your opinion about members promoting products here?
"Tom, thank you for your odd reference to a leaky duck. It is a bit off topic since I was not asking…"
yesterday
Tom Delconte commented on Kurt Shafer's blog post What is your opinion about members promoting products here?
"Shameless self promotion here sucks like a leaky duck!"
yesterday

© 2014   Created by Lawrence Berkeley National Laboratory.

Badges  |  Report an Issue  |  Terms of Service