Sealing attic floor & moving/reblowing insulation
#1
01-15-19, 11:44 AM
Sealing attic floor & moving/reblowing insulation
I want to seal all the penetrations in my attic floor, and then add more loose fill insulation to the attic. The attic already has loose fill insulation. I'm not sure what kind. My house was built in early 1980 with cheap materials, and the insulation is white and seems fluffy like cotton. The interior of my attic is very short (4.1') tall.
I don't have any can lights. Just once ceiling light junction box, and a bathroom fan. As long as my bathroom fan is rated for insulation contact, should I just add spray foam around the fan perimeter? Should I box it in some kind of protection?
I already used great stuff spray foam to seal the interior wall top plates.
In order to install soffit vent baffles, and to seal my outside wall plates in the shallowest part of my roof, I have to move a lot of insulation out of the way so have room to work.
The part about his project that worries me the most is how to handle moving and reinstalling that insulation. Should I just rake/scrap it away, and then push it back by hand, or should I try to re-blow it back into position? If so, how? Does it make the much difference whether I push it or blow it back, since I will be adding more on top anyway?
When all this is done, should I try to create a crawling path/catwalk in the middle of the attic of just fill in everything except the hatch? My attic has trusses. Without added wood support the crawling area only has 3.5" from the top of the drywall ceiling to the top of the truss member.
Or, could i just create a path of fiberglass batt insulation instead? I have already have a some batt insulation that I could use and can't return.
I don't have any can lights. Just once ceiling light junction box, and a bathroom fan. As long as my bathroom fan is rated for insulation contact, should I just add spray foam around the fan perimeter? Should I box it in some kind of protection?
I already used great stuff spray foam to seal the interior wall top plates.
In order to install soffit vent baffles, and to seal my outside wall plates in the shallowest part of my roof, I have to move a lot of insulation out of the way so have room to work.
The part about his project that worries me the most is how to handle moving and reinstalling that insulation. Should I just rake/scrap it away, and then push it back by hand, or should I try to re-blow it back into position? If so, how? Does it make the much difference whether I push it or blow it back, since I will be adding more on top anyway?
When all this is done, should I try to create a crawling path/catwalk in the middle of the attic of just fill in everything except the hatch? My attic has trusses. Without added wood support the crawling area only has 3.5" from the top of the drywall ceiling to the top of the truss member.
Or, could i just create a path of fiberglass batt insulation instead? I have already have a some batt insulation that I could use and can't return.
#2
01-15-19, 01:20 PM
Group Moderator
You're in for a fun job... NOT! I use a rake or shovel to pull old loose insulation out of the way. When done I just push it back and try to fluff it up as best possible. Then you can come back later with another layer of blown in insulation to really seal things and improve your R value.
If you had just one small area to work I'd just shimmy out balancing on top of the joists. Since you'll be doing the whole attic it's helpful to have a small sheet of plywood or scrap boards to lay across the joists so you can crawl all the way to the edge to work.
If you have machinery like attic vent fans or HVAC in the attic then creating a catwalk above the insulation level can be very useful. If you have nothing in the attic that will require servicing then don't bother.
If you had just one small area to work I'd just shimmy out balancing on top of the joists. Since you'll be doing the whole attic it's helpful to have a small sheet of plywood or scrap boards to lay across the joists so you can crawl all the way to the edge to work.
If you have machinery like attic vent fans or HVAC in the attic then creating a catwalk above the insulation level can be very useful. If you have nothing in the attic that will require servicing then don't bother.
