Trapped space between roof and ceiling
In renovating a rowhouse in Philadelphia, I ran into problems with a drop ceiling in the two bedrooms, which are at the front and back of the house.
I now plan to raise those two ceilings all the way to the rafters.
This means that there will be trapped space above a central hallways, a small central bedroom, and the bathroom, all in the center of the house.
There are brick walls to adjoins houses on both sides.
The open space that used to run from front to back will no longer exist.
I am concerned about trapping hot, humid air in this middle section.
Can I create enough air flow in this area by adding wall vents in the front and back bedrooms that go into this area?
If not, how can I deal with this?
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Replies
How is the roof insulated?
"I now plan to raise those two ceilings all the way to the rafters."
Do you mean rafters -- sloped pieces that support the roof -- or joists, horizontal pieces that run below the rafters and support the ceiling?
Normally houses of that vintage the insulation goes right above the ceiling and there is a space between the insulation and the roof. If you are in fact raising the ceiling to the rafters you are creating a cathedral ceiling. You need to read this article about how to insulated it properly:
https://www.greenbuildingadvisor.com/article/five-cathedral-ceilings-that-work