Blown in insulation questions?

[Scott Duncan]

I'm getting ready to do blown-in insulation in my walls and have a bunch of questions. My first step was to get a price for a contractor to blown-in fiberglass at $3500. The price of cellulose material to do this job is 1/10 of this so I have decided to do it myself. I have a

100-year-old Dutch Colonial that is 36 feet long and 24 feet wide. My location is Lexington Massachusetts.

Cellulose vs Fiberglass?

A fireman friend of mine told be not to use cellulose because the fire proofing treatment can leach out over time, especially since there is no vapor barrier. Is this true? He said to use fiberglass just because of the fire proofing aspect of it.

If I decide to use fiberglass, can I rent the equipment and get the material do this job myself? A lot of what I see on the web seems to suggest "professional use only" and I haven't seen the material anywhere. I have experience working with hazardous materials and know how to do the job safely, I just don't know where to get the stuff. I've checked a few local lumber yards and the Borg (Home Depot/Lowes) with no success.

If I go with cellulose, where is a good source for that? I found that Lowes sells Cocoon brand and rents a machine but no one there knows anything about it. The machine they have seems to be set up only for blowing stuff in your attic and not the walls. The hose is 2.5 inches in diameter and only 35 feet long. Their web site talked about drilling 1 1/8 holes through the plaster at the top of the wall cavities but they only offer this short 2.5 diameter hose with no adapter or reducer. They also talk about leaving the machine outside of the house yet they only offer a 35 foot hose? It would probably have to be more than twice that length to do a two-story house. Can any one recommend another source besides Lowes?

Also, is it possible to blow insulation into a stud cavity with only a hole at the top? The stud cavities are air tight and this seems trying to blow up a paper bag that is already inflated ? you just can't blow up any more than full or it will pop. How does the air escape?

Thanks in advance for your help.

Scott

[Speedy Jim]

To get the wall spaces really full, you need an exit hole for the air. You can make up your own adapter to fit the hole you drill. Get extension hose for ShopVac, etc. Definitely leave the machine outside; you want to minimize any dust.

More questions answered here:

Jim

[<BKS>]

In Massachuesetts, NSTAR gas customers get a sigificant rebate on all blown-in and batt installation. Up to $2000 can come back to you. Not sure if it applies to gas---call them.

For about $1500 (after rebate) I had one of their approved contractors come in and blow in fiberglass tufts into my old farmhouse in Maynard, Mass. which is about 1600 square feet. Note, if you have vinyl siding (like me) or shingles, it's easier for them to drill the holes required. I would not let them drill in fancier siding....

Bruin Insulation out of framingham did a super neat and clean job---the best, most professional and cleanest contractors I've ever worked with. I'm pretty handy and have put a bathroom in myself, but after watching how fast and efficient these guys are, I would gladly hire them again. I couldn't find anywhere to rent equipment for blown in fiberglass tufts (Cocoon easy---home depot) and hate working with insulation.

The air escapes any way it can. Mostly around the hose and hole, but in my case, it blew some dust through the electrical outlets and in a hole in the envelope in a bathroom I was remodeling (oops, should have covered that up).

Good luck!

[Big Jake]

Loose fiberglass is awful to work with. If you go that route, you will itch for days and days. You will also need to throw out whatever clothes you wear that day.

I have insulated about a dozen houses with cellulose, and I am told that, installed correctly, you get slightly better R-values from cellulose than fiberglass. Here in WI, there are many tool rental places that rent insulation blowers, but Home Depot gives it to you for $.01 for 24 hours if you buy at least 10 bundles of Cocoon Insulation (Made in WI).

I whine when they try to give me less than 40 feet of hose, and usually get around 75 feet. Buy shop vac hoses and adapters for special situations.

No matter how good you are, a pro will probably be able to cram 15-20% insulation into your house than you can. If you can get the utility company to give you a big rebate on the job, it really starts to make sense.

Best of Luck!

JK