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: 3718

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

Photos

Loading…
  • Add Photos
  • View All

Latest Activity

Profile IconBrian Coverstone, Charlie Ouellette, Karin Haerter and 1 more joined Home Energy Pros
10 hours ago
Juan added a discussion to the group Energy Auditing Equipment for Sale, Trade or to Purchase
Thumbnail

Need Energy conservatory Blower door 3 + DG-700

Hello thanks for taking the time to read this post. I am currently looking for a blower door…See More
20 hours ago
Juan joined allen p tanner's group
Thumbnail

Energy Auditing Equipment for Sale, Trade or to Purchase

Discuss the pros and cons of the equipment you are interested in prior to purchase. Post equipment…See More
20 hours ago
Caoimhin P Connell replied to Rodney Fox's discussion Radon: Truth vs. Myth
"Good morning, Mr. Cullen – As I mentioned in another post – for the purposes under…"
22 hours ago
tedkidd replied to Rodney Fox's discussion Radon: Truth vs. Myth
"If putting the house under positive pressure using fresh air helps mitigate not just radon, but…"
23 hours ago
Rich Manning replied to Rodney Fox's discussion Radon: Truth vs. Myth
"Tell them the truth as you know it, and back it up with the facts!!"
23 hours ago
Rich Manning replied to Charles Ryan Weitzel's discussion Oil Fired Boiler Being Used as the Heating Source in Two Air Handlers of a Historic Home
"Yes, its a Hydro-air system. It uses one boiler to supply hot water to the coil in the supply side…"
23 hours ago
tedkidd replied to Rodney Fox's discussion Radon: Truth vs. Myth
";) I love uncovering absuedities... Funny how creatively and vehemently people will argue against…"
23 hours ago

© 2016   Created by Lawrence Berkeley National Laboratory.   Powered by

Badges  |  Report an Issue  |  Terms of Service