Insulating the attic in a brick home
I am getting ready to insulate the attic of a brick home that was built in the 1950s. I have all the old insulation removed and plan to blow in either cellulose or fiberglass insulation.
Around the perimeter of the attic there is a 1 inch gap between the brick and sheathing on the exterior walls. These gaps appear to extend to the foundation and were not insulated at all and just vented into the attic. I have a couple of questions.
Should these gaps be insulated (blow insulation into them)? I’m assuming the gap should be left open as I think it is meant to allow moisture that seeps through the brick to evaporate.
Do these gaps need to stay open to the attic or should they be sealed off at the top of the wall plates and insulation installed over them? On one hand leaving them open would allow hot air and evaporated moisture to escape into the attic. On the other hand, it leaves a fairly large opening for air to escape the structure below.
Any advice you can provide would be appreciated.
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