Sunday, October 3, 2010

A Low Air Infiltration Pet Door

We had a blower door test recently, and one of the big air infiltration leaks in the house was our pet door.  The pet door leaked so badly that it had to be temporarily sealed off just to finish the blower door test.
This was a bit disappointing as we had paid extra for a double flap model that was supposed to provide good sealing.


While looking around for a good solution, I happened to read a blog on a new home that was being built in which they were enthused about the pet door they had installed.  It was a Freedom Pet Pass pet door, and in looking into it, it did seem like it might help with the air infiltration.

We ordered and installed one, and its been in use for couple months. We are quite happy with it.  It seals very well -- I cannot detect any air leakage even with a smoke pencil.   It also eliminates the problem we used to have with the flaps on the pet door banging noisily when it was windy.

The installation was a bit more involved than the other pet doors I've put in, but not that difficult, and the result is a near air leak free door.

The reason this door works better is the double magnetic seal that it employs.  It basically has one full magnetic seal for the dog going outside to inside direction, and a 2nd full magnetic seal for the dog going inside to outside.  This approach of using separate seals in each direction allows the use of face type magnetic seals with good contact area.

This shows the double magnetic seal arrangement.


View from the inside of the completed pet door.
The door does not include any "tunnel", so be prepared to frame in and trim the little tunnel through the wall.

While estimating energy saving for air infiltration improvements is very difficult, I had a very rough go at it and came up with about $30 per year in propane savings for our case.

Gary