Attic access location
tjones1014
| Posted in General Questions on
Climate Zone 3A/4A – N GA area
Full gut reno
Our attic is unconditioned & ventilated. We have a bonus room upstairs that will be conditioned. We’re taking careful precautions to make sure this is well air sealed from the attic space. I’m looking for advice regarding where to put the attic access. Is it better to put a well insulated attic access door with weatherstripping inside the conditioned bonus room? Or would putting a pulldown attic door with a ladder in the unconditioned attached garage be best?
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Replies
tjones,
There's a case to be made for either choice. I'd put it in the garage. It makes any work you do up there a lot less intrusive to the house and keeps it cleaner.
Check your code to see what it requires as a fire separation between the ceiling and attic. above.
Thanks! On the subject of air sealing/insulation, I'm also trying to figure out the detailing around the bonus room and could use some help.
The plan was to have batt insulation in the wall cavities surrounding the room and drywall the interior walls of the room. Do we need something on the other side of the insulation (on the side of the vented attic) as well?
We also planned to have blown-in fiberglass insulation on the attic floor (on top of the ceiling of the conditioned spaces below). If we make sure the ceiling drywall is air sealed well, do we need any other type of air barrier in the attic? Or are there any other measures we can take to make sure we're separating those spaces effectively?
tjones,
The walls would benefit from an air-barrier on the outside - house wrap would do. The ceiling is fine, although cellulose suffers much less from wind-washing that blown fiberglass.
Insulating bonus rooms is tricky. There is some good advice in these articles:
- https://www.greenbuildingadvisor.com/?s=bonus+rooms
- https://www.greenbuildingadvisor.com/article/insulating-the-roof-of-a-bonus-room
- https://www.greenbuildingadvisor.com/article/detailing-a-bonus-space-in-a-high-performance-home