Air space between brick and wood
I have an older house (built between 1920’s and 1930’s). The original house had clap board siding. A previous owner was a mason, and installed a brick veneer. There is an airspace between the two that is at least two inches wide. Right now I am having trouble with flying insects and more ending up in that airspace. Knowing that I have to find the holes that allow the insects in, I was looking for a way to insulate that space to keep air flow to a minimum.
1. Do I want to stop airflow in the space between the brick and pine clapboard? My main concern here is the buildup of moisture.
2. If stopping the airflow is the correct thing to do, does anyone know of a product to use .. I was thinking about a foam type product, slow cure, that I could pour into the cavity and allow to rise up filling the void.
Thanks for any help in advance.
Chris
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Replies
Chris,
You are right to be concerned about moisture. If you want to insulate, you should concentrate on the cavities in the wood framed wall and leave the space behind the brick the way it is. There are several foam products available for professional use that could be used to fill behind the brick but that would be absolutely the wrong thing to do. Brick is quite porous and the vent space is necessary.
Christopher,
Q. "Do I want to stop airflow in the space between the brick and pine clapboard?"
A. No! The more airflow, the better. All brick-veneered homes should have such an air space (although most modern homes have less than 2 inches). The air space allows wind-driven rain to drain down the back side of the brick veneer, and if the space is well ventilated, it aids drying.
If you think your wall is drafty, with too much infiltration, you'll have to do your air sealing work from the interior, as Torsten suggested.