I did an audit yesterday and found out that a single doggy door was responsible for 1,300 CFM50 of air leakage (in an already-leaky house...total leakage of 5,300 CFM50 and only 2,200 square feet of conditioned floor area).

So, what to do about this doggy door? I could spent some time thinking of a clever way to address this, or do some research online, but I thought of y'all first, as the preeminent professionals.

Any advice?



Views: 609

Reply to This

Replies to This Discussion

Replace it with one that has two doors (one on each side) & magnets - they work great

I can't recall the brand but the last few I got were at Home Depot & I think I even saw them at Lowe's

Most pet flaps have some sort of positive closure, magnet or similar, and for the most part they work OK, although some air works its way around the flap's perimeter.

What I think happened here is that the blower door test pressure, which far exceeds natural pressure, overwhelmed the flap's magnet and it swung open, allowing an extra 1300 CFM. That should not occur under normal, non-blower-door test conditions.

Let me call Bull - if the blower door could pull it open, that means the wind will easily blow it open as it wasn't able to resist one pound of pressure (PSF) --- for more see Pascals & Pressure 

Either the magnet is shot, it is filthy, or the unit is worthless, which is one reason why I like the double flap system


I appreciate the frankness Sean (I really do).

Let me look into this flap again, and maybe these folks are looking at the POS series pet flap.

The blower door test pressure of 50 Pa is roughly equivalent to a 20 mph wind, which is quite uncommon in most areas

Unless you live in Oklahoma.

Thanks Curt.

I have to look at this flap again. It appeared to fit by friction.

Locating pet doors on a relatively sheltered wall of the house could help. I've been designing a two door doggie airlock in my head. It would be disguised as a bench (or banco in my neck of the woods), be heavily insulated, and vented to the exterior to disperse pulses of wind back to the outside of the house. If the vent could exhaust around a corner from the exterior flap that would be best, and it should have some kind of a flapper to reduce air coming in it. Or build the whole thing on the outside as a tunnel with exterior door at the end and vents both sides.

Locating Doggie Doors on South or East walls helps a lot.

worry more about the other 4000 cfm

the air coming from the dog door is fresh air

Where is the other 4000 cfm coming from?


I recently had a similar situation, only the doggy door was big enough for an adolescent to crawl through. When I told my client she should consider replacing the door, she waxed nostalgic about the happy times when her dog and children would chase each other through the door. She made it clear she'd never replace the thing. I still haven't done any work for her.

Another trick I've seen is to dedicate the bottom half of a cabinet as a vestibule/mud-room with a second air-lock flapper like Peter suggests.  Obviously you'ed need to design some people access to clean it out occasionally, but I agree with Glen re. the other 4000 cfm. 


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

John Proctor commented on Chris Laumer-Giddens's blog post Sparky Doubled the Air Leakage in this Home!
"Nice job on the house -- bad job on Sparky's high tech hole."
4 hours ago
Jeffrey Gephart shared Chris Laumer-Giddens's blog post on Facebook
4 hours ago
Diane Chojnowski's video was featured

Raising the Bar within the Weatherization and Home Performance Industry

The Weatherization Assistance Program (WAP) was created in 1976 to assist low-income families who lacked resources to invest in energy efficiency. Through th...
4 hours ago
Carlee Quintas posted a blog post

A Green Home for the Holidays

The holidays here, which means house parties and guests galore, not to mention the aunts, uncles,…See More
4 hours ago
Profile IconAmos Dunham and Grzegorz joined Home Energy Pros
5 hours ago
Alfie Davis posted a photo

Handschuhe im Wandel der Zeit

Im Laufe der Jahrhunderte haben sich #Handschuhe zu dem entwickelt, was sie heute sind:…
7 hours ago
Dennis Heidner replied to Rod Fox's discussion Utility Meter Accuracy
"For Rod, second part... When I see really large electric services... my first reaction my be…"
17 hours ago
Dennis Heidner replied to Rod Fox's discussion Utility Meter Accuracy
"Rod,  I did see earlier that you had calculated the loads.  The key is even though a…"
17 hours ago

© 2015   Created by Lawrence Berkeley National Laboratory.   Powered by

Badges  |  Report an Issue  |  Terms of Service