Blowing Insulation into attic

Q: I'm looking into blowing insulation into attic. I think that Home Depot blown insulation come out to about 40 cents per square foot for R-38. I also had a quote from a professional that is $1/square foot. Does this sound right (want to make sure I'm comparing apples to apples)?

In addition I was reading some instructions on how to blow, and it said to keep the machine _outside_, however I don't think that's possible for me to blow into my attic. Is it OK to run these machines indoors? (the one from Home Depot in particular)

Any tips or advice?

A: When I looked into doing my house, the cost difference between doing it myself and paying somebody was minimal since the pros buy in such big quantities.

You also need somebody to install the appropriate baffles at the eaves so that the vents don’t get blocked, and you should also consider whether there are any open air paths into the attic that need to be sealed.

I was happy to spend the money to have somebody else do it.

Q: I want this crap OUT of my house. I sucked a some out myself when I remodeled my kitchen, but I would not mind getting it ALL out and replaced with something better. (And I do NOT want to do it myself, that stuff is super nasty.)

Any idea on how much it would cost to first SUCK out all the old blown in stuff? The insulation in my attic is super super nasty stuff. It’s this burnt amber color, smells horrible, and if you happen to get a taste, very very acidic tasing. The inspector said it looks like cedar shreddings soaked in formaldrahyde. And in the summer, it can acquire a smell that is not pleasant.

A: I think I would ask an insulation contractor about that. My guess is that it wouldn’t be that pricey to suck it out, but there might be some disposal cost.

A: You might want to call “Clean Crawls” (http://www.cleancrawl.com/). My wife and I have hired them to do our attic, (their field rep, Jay, was very knowledgeable). Additionally, if you have Puget Sound Energy supplying your electricity, you are eligible for rebates on attic insulation, (we saved about $400).

However, we have only 455 sq. ft. of attic, and that is small because of the shape of our roof; in most houses the attic will equal the square footage of an entire floor, (I figure we saved on our materials cost, but labor, machine set up time, etc. will probably be pretty much the same for everyone).

A: CleanCrawl

Eastside exterminators (they also do insulation work)

And there is another one in the prime card site

A: Did you then have someone install rolled / paperbacked / whatever its called insulation sheets, or did you just blow something new in? I’d love if I had the clean rolled stuff in my attic, it would make it a lot easier to get around up there compared to the loose fiberglas that it currently contains.

A: I think “batt insulation” is the term you’re looking for.

Blown in cellulose is considerable better at insulating than fiberglass. Not only does it fill around uneven shapes (which batts don’t do), but it acts as an air barrier, which is something fiberglass doesn’t do.

It’s also cheaper, and you can work in an attic with it (I understand your opinion about loose fiberglass).

A: Ahh, yes I remember hearing about the cellulose on this list before. Based on how the joists in our attic are I won’t be converting it in to storage space, but I do get up around there to pull wires so it may be a decent option. It would have the same ‘compaction’ problem when I’m walking around trying to find my footing on the hidden beams though - I have tons of spots in my attic where the insulation is really thin from me standing. Is cellulose more robust against that? (I imagine just being able to fluff it up with my hands would be a big benefit over the fiberglass anyway)

A: I had cellulose insulation blown in to the level of the top of the joists. Then I took the jeans-based insulation from Seattle Environmental Homecenter and laid it on top of the joists myself. I’m figuring I’ll need to pull up and re-install those jeans bats when I run new wiring and I didn’t want to have to wade through cellulose covering all the joists.

A: Yeah, I put in a whole-house fan last spring and had the same issue.

You do get compaction, but it seems to me that it’s not as bad because the cellulose is considerably more dense to start with and it’s easy to move it around when you’re done. I take a small dustpan up and use it to scoop the insulation to the sides and then back when I’m done, and that works well for me.

A: A leaf rake works wonders when spreading out blown insulation or moving the fibreglass kind into the hard to reach places.

A: It was about 5 years ago, so I don’t remember who did the work, but it was pretty simple and they did a nice job. All the good installers have a truck-mounted blower, which is quieter (in the house) and moves the product more quickly and with less mess.

The concerns are:

1) Seal any holes up beforehand (I had a cavity from the second floor that was open into the attic and would have take around 20 cu ft of insulation to fill, so I had them seal that up ahead of time
2) If you have skylights, the shafts need to be insulated separately with fiberglass batts

3) You need baffles at the eaves to provide airflow.

4) Recessed lights need to be handled properly. Older housings need to have some airspace between them and the insulation – there are baffles you can get to cover them, and sometimes installers just use open cylinders of flashing to keep the insulation off them. You will definitely lose heat through those kinds of housings, and if you cover them there is heat/fire hazard.

Newer housings (which have IC (Insulation contact) on their label someplace) can have the insulation right up next to them.

5) Attic access covers need to be well handled, and it bit of a pain to get them to seal well. Mine has fiberglass around it so that you don’t get a shower of cellulose every time you open it.

My one regret is that I didn’t have them put in more depth – I have about 8”, and I would be happier if I’d paid a little more for an extra 4” of insulation.