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[DaveWertz]

Well Im pulling the trigger and plan on blowing insulation into my walls. Im torn about what to use. My house has metal siding with old wood siding under that. Im seeing some really good things about the cellulose blown insulation. What are some perks of cellulose that you dont get with fiberglass and vise versa? Cellulose just seems to be the better choice and better bang for the buck IMO. I will be blowing this in from the outside. The house is 100+yrs old and has no insulation, Im tired of temps going up and down in the winter and summer. The house does not hold heat what so every nor does it keep heat out in the summer months. The main this is that cellulose has borate and Im not sure how this affects wiring over the yrs. And how to both handle moisture?? I know cellulose is mold "resistant" and fiberglass is not. What are some of your opinions....

[bruey]

I think it's your personal choice. Both do a great job. If you have to worry about mold you have bigger problems than just insolating, not a worry of mine. The only draw back to cellulose would be it does compact over time. Best insolation today is that new foam that has been out for a few years but you spray it on which might be impossible in your application. If I ever build another house that is what I will use.

[tawilson1152]

Sounds like my house. I did cellulose 20 years ago and have had no problems or regrets. Mine is balloon construction so I could blow most of it in from the attic. I used a short length of chain tied to a rope to get the insulation to settle past wiring.

[hondaracer2oo4]

Dave,

  This can be quite the touchy subject. The major issue with blowing cellulose into the wall is moisture. If the wall, outlets, floor, windows etc aren't completely air sealed any hot air that gets into the cavity and hits the cold outside wall will instantly condense and in turn soak the cellulose causing rot and mold. Some people have zero problems filling the walls and some people rot the walls right out and can't keep paint on the outside of the house because of the moisture trying to make its way out. I have been one at a time pulling my walls down in my 200+ year old house and sealing the exterior sheathing up tight with chaulk and foam then insulating with fiberglass and then covering the whole wall with 1/2 foil faced foam board to break the thermal bridge through the studs from the outside wall to the inside wall. I can always tell where the air leakage has been when I pull a wall down because it will be wet/frozen in the winter or you can see where the exterior boards have been stained by moisture. After I cover with sheet rock I chaulk all of the edges to make a nice tight seal. I know that blown in is quick, easy and cheap. But if your going to do something I like to try to do it right and do it only once. If you do blown in make sure that you go around with a fine toothed comb and chaulk everything you can to prevent ANY air leakage. After all air leakage is your biggest enemy.

[beeman]

i to live in old house the thing that scared me as the old wiring get rid of old plaster leigh walls mind you when hanging drywal i dont think they used a tap mesur thank goodnes for tap and mud

[Sprinter]

The cellulose here doesn't grow mold, and doesn't loose r value as it settles(like glass does). It actually increases R, in walls it's the space it leaves behind that's the problem. When blown in professionally it seals and no wires stop it from filling cavity. They do it thru two 1" holes and its as solid as the blocks you can buy at the store. It's more R/inch than fiberglass and just a bit less than Roxul (which can also be blown in) provided your contractor has the equipment or material. mineral wool or Roxul keep their R value when wet, fireproof and no mold at all. And the only thing spray foam is better at is application, structure stiffening.

[DaveWertz]

Im not really worried about mold I just like the idea that its mold and insect resistant. I will be re caulking the windows from the outside to make sure water cant get in. I see there are two ways of doing it. Loose pack and dense pack which requires a longer smaller hose and takes a bit more cellulose but reduces the settling from loose pack. Im only doing first floor and attic for now. Attic already has it im just rolling fiberglass over top of that.

[hondaracer2oo4]

Dave,

   The major concern is the warm air from inside the structure making its way into the wall cavity and hitting the cold outside sheathing and condensing causing rotting of your structure of the home. If you still decide to go this route you will want to do dense pack in the walls. If you do loose pack it will settle over time and you will lose a certain amount of insulation space at the top of the wall. As far as your attic goes I would forget the rolls of fiberglass and blow down more loose cellulose. Better R value then fiberglass and fiberglass batts have to be installed butted right up/not compressed at all etc. Cellulose you just blow it down.

[DaveWertz]

Dense packing seems to be the key to get away from moisture. At least thats what im seeing from others. Some have loosed packed and had moisture issues.

[DaveWertz]

I finally got my attic fully insulated! I went ahead and did the attic as this seems to be from what im hearing the best way for my money to go. I went with r30 attic from home depot. It was 4 bucks cheaper there than lowes or anywhere else. It took me about 3hrs by myself to do a little under 1000 square. Would have taken allot less but the attic is separated by 3 different rooms. What a pain it was!. I got 32 rolls and only needed 28. I sure hope my house holds heat and keeps up to temp when its real cold out! Tine will tell if I see any difference.

[hondaracer2oo4]

Sounds like you went with rolled fiberglass. Just curious why you didn't go with blown cellulose in the attic.

[DaveWertz]

Only because of settling.  Without dense packing cellulose it will settle considerable. The attic had 10inches of blown insulation 10yrs ago. It is at about 5inches now. So I got some r30 and rolled it over top of the cellulose. The cost was about the same. I think cellulose in the attic would have required much more material to over time get the r value I wanted

[Sprinter]

As cellulose settles it does loose R value like glass. Cellulose itself is an insulator, glass is not. Glass insulates by trapping air and preventing movement. If you compress an R30 bat to fit in a stud wall it only has an R19 value.
The perimeter of your attic is where the most heat loss happens. Especially the area between the top wall plate and roof, also the hardest area to get to. Using baffles or the foam board that folds up attached to roof trusses all the way to the soffit, allows cold air movement for roof and separation from the attic space itself.
Injecting spray foam at the corner bucks is another big Spot to do. Best seen with an infrared camera and where to get access. Look into doing a heat loss inspection by IR camera, worth ev.ery dime.

[DaveWertz]

I only did the floor in the attic. I butted the glass right up to the bottom of the truses so air could still vent threw. I got them tight as can be. I hope to see some heat savings

[Sprinter]