Are sealed electrical boxes needed for the airtight drywall approach when using drywall gaskets?
I’m planning to use the airtight drywall approach to air-sealing in a single room renovation.
As I understand it with internal walls the concern is penetration into the attic. So I’m using drywall gaskets from Conservation Technology to seal the drywall at the top (and bottom plates). If the top-plates are well sealed do I need to worry about air-sealing the electrical boxes? Warm air could penetrate but not rise into the attic (or more likely in Zone 2) warm air won’t ever get from the attic behind the drywall to enter the room.
The external walls are block and won’t have dry-wall on them; they will have American Clay. So the drywall gaskets here will just be for the ceiling/wall join. I know that sealing electrical boxes in external walls is recommended, but I assume that’s for air penetration from the outside (not top) which isn’t a concern for us.
On a related question: in cooling season is air-sealing the ceiling so crucial? Why doesn’t the AC cooled air stay low in the house while the super-heated attic air stays high? Is it primarily a question of pressure or wind wash rather than temperature? Or is this an example of something that’s crucial in warming season (cold outside/warm inside) but not as crucial in cooling season (where low to the ground sealing is more important, e.g., under doors).