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: 3351

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.  Home Energy Pros is sponsored by the Better Buildings Residential Network.

Latest Activity

Eric Kjelshus replied to Rod Fox's discussion Does calcification affect electric water heater aquastat temperature sensor performance?
"Those 240 Volt aquastats shut off and then on kinda quick back on.  The older the tank the…"
3 hours ago
Profile IconMike Norvell Sr and Jen Loomis joined Home Energy Pros
8 hours ago
Rod Fox replied to Rod Fox's discussion Does calcification affect electric water heater aquastat temperature sensor performance?
"Well I'd love to tell you folks I found an answer, but I did not... I went to my…"
12 hours ago
Rod Fox replied to Kevin Eigel's discussion What is the best energy auditing software?
"I've been trying to answer this question for many years and have not yet found an answer.…"
12 hours ago
Jerry Lawrence posted events
12 hours ago
Jan Green commented on Theresa L Gilbride's blog post Find out who's building some of the best-performing homes in the country today with DOE’s Tour of Zero
"Thank you for sharing! "
14 hours ago
Jan Green commented on Theresa L Gilbride's blog post Find out who's building some of the best-performing homes in the country today with DOE’s Tour of Zero
"We have one builder in Arizona on the DOE list.  Good information for a blog!"
14 hours ago
Beverly Lerch posted a photo

FIREPLACE FASHION COVER

A Fireplace Fashion Cover will insulate and isolate your fireplace against drafts and heat loss…
14 hours ago

© 2015   Created by Lawrence Berkeley National Laboratory.

Badges  |  Report an Issue  |  Terms of Service