Adding Extra Blown In Insulation To Attic

Mike Finley

Before the heating season starts I think it's time to add some extra blown in insulation in the attic of my house. Is there any do's or don'ts can you do too much? What would be your considerations? We've got some up there, maybe 12" on average, but it's been stomped and moved around over the years of remodeling projects.

reveivl

There's no such thing as too much, but you get diminishing returns on it. Make sure you don't block the soffit vents.

__________________
From where does knowledge come? If you need to know what is in a box, you could ask someone (not reliable), you could pray, (not useful), you can consult with the scripture (not helpful) or you could open the box (science)

superjay5

what kind is up there right now???

Mike Finley

The blown in kind? That's about all I know about it. House built in 1984.

neolitic

Use fiberglass--fiberglass over cellulose is okay, cellulose over fiberglass--not so much. I'd guess anything over 14" a waste of money in your clime.

erik123

Just my 2 cents... I have only done a 1/2 dozen or so insulation jobs and only had one helper fall completely through the ceiling. I think roll or batts are cleaner and easier in the long run. No need to rent a blower, set up clean up etc. plus it can be a one man job with batt insulation.

woodmagman

A fluffy 12" typically nets you a R-40 for blown in insulation. If you have packed it down over the time then it would be more productive to send in a fluffer...ohhh, thats not what I meant. The definition is the same. You would like it to have as much volume as possible... compressed is not good.
A small leaf rake will do wonders.
Your ventilation is just as important. Ensure the eaves are not blocked and even add additional roof vents if you find that it is really hot in the summer up there. It will assit in the life of your shingles as a bonus.

mdshunk

I've been in attics where the blown in cellulose is maybe 4" at one end and 2 feet at the other end, due to the prevailing wind that was blowing through the gable end vents.

joasis

And I can't believe there are still contractors that have a thing for fiberglass.....cellulose is the way to go, and if wet applied (yes, sprayed) in an attic, the starch will take on a "set" and not be subject to movement. Another fact is as cellulose settles, it doesn't actually loose as much R value as some think.....density plays a roll as well...just smaller air pockets.

Check out http://www.fiberlitetech.com/fiber_lite.htm for the real deal on cellulose. Fiberglass doesn't come close.

__________________