DIYbanter - View Single Post - Replacing attic insulation with a whole house fan

Art Todesco

On 3/20/2014 8:18 PM, wrote:
Hi,
I've recently bought a 1930's house with a whole house fan that discharges directly into my attic. The attic has gable vents, so plenty of discharge space is available. The attic floor joists are 2x6's and the fiberglass insulation is ancient... it's matted down to about 2" high. I'd like to replace the insulation. It's covered in a heavy layer of dust, probably most of which was deposited over the years by the whole house fan.

Is it ok to replace the fiberglass insulation and just let the dust settle on it over time? I have little interest in spending money to cover the attic floor with plywood or OSB just to keep the fiberglass relatively dust free. Should I worry about this sort of thing?

All comments appreciated.
Regards,
Theodore

I did this in a house I once owned. It was trussed construction and
there was about 3-4" of blown in fiberglass. I has a removable exhaust
fan mounted in the scuttle hole ... it was designed for that purpose.
Later I decided to add more insulation and had about a foot of cellulose
blown in. But before doing so, I build a 2' wide walkway. Actually, it
was a 2' wide crawl way; the peek was only 4' high right along the crawl
way. First I put 2" thick of foam board down with the final layer of
plywood for walking ... I mean crawling. Knowing the blown in
insulation would be all over the crawl way, I put vertical pieces of
cardboard along each side. Never had a problem with the fan messing
with the cellulose insulation. When 1st done, it was very thick and if
you touched it, you would propagate waves in it. But, that quick
stopped as the air eventually left and it settled to a less thick
coverage. After using the crawl way to store many things, like
Christmas and Halloween decorations, I only wish I had made it 4' wide
instead of 2'. BTW, I was able to get the 2' x 8' pieces of plywood and
foam up there because I had the front of the house opened for a
remodel/fix up. So, I cut a 2' wide hole in the sheathing and slid in
the 8' long panels. And then covered the hole in the sheathing and put
new siding over the entire wall.