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: 4683

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

Forum Discussions

Origin of guarded blower door testing

Started by Kim Tanner in General Forum. Last reply by Eric Kjelshus yesterday. 9 Replies

Electro Magnetic Fields (EMF)

Started by Barry L NewDelman in General Forum. Last reply by Daniel Cullen Aug 10. 5 Replies

When is it too windy to use blower door?

Started by Brandon Walton in General Forum. Last reply by Iain Walker Aug 10. 17 Replies

Latest Activity

Profile IconArmstrong SMith, Eric Buchalter, Liza Gonzalez and 3 more joined Home Energy Pros
15 hours ago
Eric Kjelshus replied to Kim Tanner's discussion Origin of guarded blower door testing
"That same house that meet highest sealing rate in early 1980 we went back and super sealed it and…"
yesterday
Jill Cliburn posted an event
Thumbnail

National Solar Conference and NZE Decathlon at University of Colorado

October 9, 2017 at 6pm to October 12, 2017 at 7pm
yesterday
tedkidd replied to Kim Tanner's discussion Origin of guarded blower door testing
"Brendan, Eric, great stuff!"
yesterday

Photos

Loading…
  • Add Photos
  • View All

© 2017   Created by Lawrence Berkeley National Laboratory.   Powered by

Badges  |  Report an Issue  |  Terms of Service