Blown-In Insulation Question

[Larry Weil]

I have an older house that was originally a summer house, but was later converted to year-round use, located in North Salem, NH.

A few years ago I had six inches of blown-in fiberglass added to the attic, on top of what insulation was already there. This helped a bit, especially in the summer, but in the winter the temperature is still quite uneven, and in real cold weather it is impossible to be comfortable no matter how high I turn the heat. The heat is oil fired forced hot air. Underneath the house in an uninsulated (but blocked off) crawl space that is less than a foot deep, so it would be impossible for anyone to go in there to insulate the floor.

I had an insulation contractor in today for an estimate on insulating the walls. The walls have vinyl siding, and the only insulation is the foam board under the siding. A couple of years ago I had the bathtub replaced, and when it was out I could see the sheathing with no insulation on the inside.

This contractor proposes blown-in fiberglass insulation. I asked him about potential problems from the fiberglass settling, and he said what they do is a two hole system, where that make holes and blow in fiberglass from both the top and bottom of the wall, and that will compact it enough that it won¹t settle enough to be a problem.

My question is if this is really a good way to go, if the two hole system really works to prevent the insulation from settling and forming a gap at the top? Has anyone here had that done and has it worked?

BTW, I called three insulation contractors, and the one that came was the only one of the three that bothered to return my call. Why do these guys bother to advertise if they¹re not going to return your call?

[ransley]

Fiberglass is about R 3.5 per inch, you dont say what was there before but R 21 isnt much. The code for your area is a minimum needed amount, not optimal. How cold does your area get, I am Zone 5 to -20f and R60 is good, but I have alot more than that. Find your temp zone map,

has good ideas and links to start at. For optimal values look at insulation co sites lie Dow, Certainteed, they have maps. Also google how fiberglass looses R value at cold temperatures, that fact and the fact the 6" you put in has settled means you probably dont have what you think you have. For walls I have read about Cellulose with glue that is pumped in damp and wont settle, the fiberglass in walls will settle. I had my walls foamed, that insulated better than anything else. If you can afford it an energy audit it should be done, maybe your utility does them free. A blower door test for about 350 will pinpoint air leaks, I think mine paid for itself in a year from all the hidden holes I had. If you get walls blown in, have in the contract that if a Thermal Imaging camera finds any defects of the instal he fixes them free or gives you your money back. Thermal Imaging before and after is the only way to find many issues.

[Joe]

These systems use plugs to seal up the siding holes after the insulation is blown in. Had it done on an old house of ours and the plugs looked awful. The insulation, however, worked great. Treated cellulose fiber is more common in our area, and it does settle. Fiberglass loses R value if compacted too much; that may be a concern.

a) They have more work than they can handle. b) Taking time to call takes time from the work. c) If you call a second time they'll know you're serious. d) The further east and the bigger the city, the less courteous people are.

If the appearance of the siding is important, the alternative is redoing the drywall and using standard fiberglass batts on the inside. That might be tempting if you have other upgrades you want to do, like electrical outlets, or plumbing or remodeling. Consider your priorities, prices and expected results and choose what you feel is best. HTH

Joe

[Sharp Dressed Man]

No doubt with the home building and construction businesses booming like they are today, they're just too busy....

[Bubba]

R-60 is good and you have a lot more than that??!! hehe. ransley, you again havent a clue what you are talking about. You can easily confirm this by doing a load calculation. In a ceiling, when you go from no insulation to the first 3 inches, you will gain your biggest energy savings. After that, whatever you add is only marginal. NOW, before you get that statement all out of whack, Im NOT suggesting that you only put 3 inches of insulation in your attic no matter where you live. I would go with what is recommended in your area but adding some ridiculous amount like you have done is just a total waste of money. Just like you though. Spend a few hundred extra to save a nickel. You should have checked with someone that knows what they are doing before you burned up your money like that. You could have saved that money and spent it on your crack habit. Bubba

[Pete C.]

I'd suggest that depending on the construction details it may not be all that difficult to either excavate the crawl space out to say 24" where it is workable, and / or to lift the entire house to the same effect.

For the blown in fiberglass in the walls, I believe there is a version with a slightly sticky binder included that helps lock things in place once it's blown in.

A good starting point for everything however is a simple blower door test and / or thermal IR camera survey to identify air leaks and the worst insulated spots so you can triage and prioritize your actions.

Don't underestimate the value of servicing the furnace and having the registers balanced. It is also possible to zone the heating system.

[Stormin Mormon]

The clue is feeling warm, no matter how high you turn the heat. Please get a humidifier, if you don't have one already. Some moisture makes a major difference. Table top models at chain stores, or have your heating guy install an Aprilaire on your furnace.

[Jim Elbrecht]

-snip-

I prefer cellulose myself- but if the contractor prefers fiberglass I'd rather have a well done job with fiberglass than an 'ok' job with cellulose. It is a bit of an art to pack it well enough to not settle- but loose enough to still insulate.

Be sure the contractor is going to lift the vinyl & drill holes only in the wood siding underneath. [you might need to wait until spring so the vinyl doesn't just crack all to hell]

I agree with a,b,c

Or doing the holes on the inside-- it tears up the whole inside- but this time of year might be an option.

Jim

[Steve Barker]

forget the fiberglass. You need cellulose. Called 'drill and fill'. And it can be done with one hole in each stud cavity. Keep calling around 'till you find someone who does it. If the house is fairly old, you may be able to do the gable ends from the attic. The cavities are usually open to the attic on the gable ends. Saves some drilling.

s

[ransley]

Buuba your statements just show what kind of ignorant idiot you are.

[Bubba]

ruunsley, your just a putz. Kind of cross between dumber than a rock and dumber than a full box of rocks. Your turn, dillrod...... Bubba