Blow in Ceiling Insualtion as Ceiling is Installed

[monteu]

Blow in Ceiling Insualtion--Celluliose or Fiberglass??

Going to put the sheet metal ceiling up in pole barn tomorrow. I have this idea of blowing in the ceiling insulation as we go rather than crawl around up there later. I have called and got prices at two lumber yards. One reccomends celluloise blow-in and the other reccomends fiberglass blow-in. Which one is the preferred insulation? I am confused.

 

[dave1949]

Blown cellulose or fiber-glass? I've only had one experience with cellulose, but I think you are going to put a lot of paper dust in the air doing it that way. It's not good to breathe, you should wear a good respirator/mask when blowing.

I think sheet metal ceilings are nice looking and should be maintenance free. Decent fire resistance too. When putting insulation above sheet metal, do you use a vapor barrier or seal the joints in some way?

 

[Luremaker]

Going to put the sheet metal ceiling up in pole barn tomorrow. I have this idea of blowing in the ceiling insulation as we go rather than crawl around up there later. We are running the sheet metal parallel with the trusses. I would put up approx three widths of 36" sheet metal and then blow the insulation on top. Then continue on and so forth. The truss would sort of act as a barrier to keep the loos insulation from falling. Make sense and what do you think?

I would blow it all up after installing the ceiling. Like Dave1949 said you will be working in dust. It is so easy to blow insulation with a helper. My son and I insulated my 40' x 60' shop in a few hours. I let him crawl around the attic while I fed the bales into the blower. Kept the blower outside the shop and there was only little cleanup required afterwards.

 

[rswyan]

Re: Blow in Ceiling Insualtion--Celluliose or Fiberglass??

One reccomends celluloise blow-in and the other reccomends fiberglass blow-in. Which one is the preferred insulation? I am confused.

While I'm sure that neither is good to breathe, I see cellulose as the less irritating of the two .... just something about breathing shards of glass I guess.

In terms of insulating, apparently cellulose provides somewhat better performance.

 

[ray66v]

I think sheet metal ceilings are nice looking and should be maintenance free. Decent fire resistance too.

If by "decent" you mean a little better than nothing, then yes.

 

[dave1949]

If by "decent" you mean a little better than nothing, then yes.

How about "not combustible" :laughing: Thinking of sparks or whatever that wouldn't be able to start a fire. If it's 29 ga., I'm sure a hot fire gets through it pretty quickly.

 

[ray66v]

How about "not combustible" :laughing: Thinking of sparks or whatever that wouldn't be able to start a fire. If it's 29 ga., I'm sure a hot fire gets through it pretty quickly.

I'll stay with 5/8 drywall.

At least then, I won't wonder if it would have mattered in a fire. :thumbsup:

I have slid pre-cut 4' fiberglass insulation batts on top of the drywall, as it was being put up. That sure made the job easier.

 

[mad_planter]

Re: Blow in Ceiling Insualtion--Celluliose or Fiberglass??

When they insulated my house they gave the option of stapling up a polyester "fabric" before putting in the ceiling and then blowing the insulation up through that to avoid having to crawl around in the attic to do it after the ceiling was in.

 

[Gary Fowler]

Re: Blow in Ceiling Insualtion--Celluliose or Fiberglass??

I think that blowing in the insulation came about because of the "crawling issue" in ceiling and some of the really tight spots sometimes go no insulation because you physically couldn t get into the small areas to put in bats. A good dust particle mask is a necessity for either. I prefer the glass insulation over the cellulose simply due to fire hazard. I know they claim the cellulose is treated for fire retarding but, I know glass doesnt burn and paper sure as heck does and small critters seem to like the paper better than the fiberglas. I also think the cellulose settles more and quicker than the glass. The trapped air is the insulator and if the fiber settles it has less insulation value.
Back to the question of when to install it. I suppose that if you were carefull, you could blow it in as you installed a few panels, but why bother. If you are up in the rafters, its going to be hot either way you go and getting the stuff level a bit at a time might be problematic not to mention time consuming on rental of the machine to blow it in. The dealer might not want his machine out for the period of time necessary for you to blow a bit and put up tin, then blow some more. Typically a blown in job is less than an hour to install a whole house system.

 

[KennyG]

Re: Blow in Ceiling Insualtion--Celluliose or Fiberglass??

Don't discount the fire barrier value of a metal ceiling. Many people mistakenly assume that fire rating is based on insulation capability. It's actually based on the resistance to burning, burning through, and transmitting heat. As a roof, 29 ga. metal is Class A rated. You would need a major fire to ignate insulation above a metal surface because it spreads the heat as it conducts it in all directions. Some people prefer the fiberglas, but the most common approach is cellulose for both price and performance.

In any case, make sure you have the vapor barrier in place above the steel.

 

[SSdoxie]

I've blown insulation in couple houses I remodeled and used both cellulose and fiberglass. Used to use cellulose just becsue of the itch factor of fiberglass but cellulose needs to be thiker to get same R factor and it does settle more, especially if moisture in the attic. I reblew my attic in current house this spring using fiberglass. Owen Corning has some white tuff out now that is "no itch", low irritation. Price works out to about same with either since you need more cellulose to get same result.
I wouldn't try blowing as you put up the ceiling, with the wind coming out the blower it will push the insulation back into a pile and make it hard to cover the few sheets you put up. Plus the blower rent is usually free if you buy certain number of bags and have the blower back in 24 hrs. Just lay a couple planks up in the ceiling joist to walk or crawl on before you finish puting up the steel. Trying to balance on the joist, watch where you are blowing, then step back to the next joist has resulted in more than one foot going through the ceiling, in this case bending the steel and poping screw loose.

 

[ray66v]

Re: Blow in Ceiling Insualtion--Celluliose or Fiberglass??

Don't discount the fire barrier value of a metal ceiling. Many people mistakenly assume that fire rating is based on insulation capability. It's actually based on the resistance to burning, burning through, and transmitting heat. As a roof, 29 ga. metal is Class A rated. You would need a major fire to ignate insulation above a metal surface because it spreads the heat as it conducts it in all directions.
.

The problem with steel in a fire is, it does a very good job of conducting heat. The heat from a fire rises to the ceiling, and is transmitted to the other side with almost no loss, igniting anything combustible. Not your insulation, your roof trusses, or furring used to hang the steel. Heated wood can ignite at temperatures as low as 500 degrees F. The steel also warps, and buckles as it expands from the heat, this allows fire, and superheated smoke to go through the gaps.

The problem is not so much when your working in the building, as when the fire ignites in an unoccupied building. Then, it can potentially develop quickly into a big enough fire, that a Class-A flame spread rating is not going to slow down.

I would not be surprised to quickly be able to measure temperatures above 500 degrees at the ceiling, directly above a very modest sized fire.