Blow-in insulation behind pegboard?

   / Blow-in insulation behind pegboard? #1  


Elite Member
Apr 21, 2012
Cascade Mtns of WA state
Kubota B-series & Mini Excavator
I have a new shop. This is good! REAL GOOD! One bay is walled off, with a door, so I thought I'd put a woodstove in that bay. It has pegboard on ALL walls, nailed on with galvanized drywall nails with the thin heads. I don't know if I like pegboard, cuz I yank tools & the hooks fall off (I think). Perhaps I can learn to like it. One guy said paint it white anyway, then the pegs will have to jam in, and will stay on.

It has no insulation in the walls behind the pegboard. It would be very easy to blow in the insulation on 3 walls, I suppose all done in one morning.

SO...can I blow in insulation into the walls behind the pegboard? Will it stay put? There will be no vapor barrier, but theres no shower or cooking or steam in my shop, no people sleeping etc - it will be cold most of the time, heated perhaps twice a week - if that.

Does blow-in insulation have fire resistance? I was thinking of a welding spark diving into a hole.

Hoping someone has experience with this. I need to make some decisions before I move in. Can't do a lot of work on it, have other fish to fry. I need a new workbench too. Soon, house projects will be TOP priority and its gonna be a long haul.
   / Blow-in insulation behind pegboard? #2  
Blown in can be cellulose or fiberglass. Both have an agent that is on the product that prevents free burning but it isn't fireproof. If you insist on leaving the insulation exposed or semi exposed Roxul is the only product I know of that a home owner can purchase relatively easily and provides a decent level of protection from high heat. However it's batt not blown in.
I'm not sure what you consider a vapor barrier in your area. However, insulation is designed to work in conjunction with products that prevent air movement. The typical setup is a house wrap on the exterior side and drywall with tape and paint on the inside. Again, I'm not sure what you mean when you say their is no vapor barrier- either side or just on the inside?
Peanut gallery idea- remove peg board, insulate then add plywood or OSB. If the shop has drywall everywhere else add drywall and then the sheathing on top of that.
Also remember about 70% of the heat loss occurs in the lid. You don't mention your plan for that.
   / Blow-in insulation behind pegboard? #3  
I can't say about the insulation, but if you are concerned about the peg board, look up "French cleat" for workshops. A little more work, but much more robust.
   / Blow-in insulation behind pegboard? #4  
Sodo, I hate pegboard. That said, sure go ahead and blow in fiberglass insulation behind it. Most of the commercial stuff nowadays is fire rated so I wouldn't be concerned at all. Your pegboard can burn but vertical surfaces hard to light especially with a 'spark' vs. continuous flame. I see your concern with an ember sitting in a peg hole but the fiberglass will just melt and not ignite.
   / Blow-in insulation behind pegboard? #5  
I don't think this is a good idea. You should have a vapor barrier between the heated space and the insulation for it to work well. If it was mine, I would pull the pegboard and put up some type of liner, if only thin particle board. I have pegboard in a lot of my shop but I have mounted to stand off strips over particle board. I also had a love/hate relationship with pegboard until I bought a large quantity of plastic hooks on ebay. They stay in place.
   / Blow-in insulation behind pegboard? #6  
I would be inclined to remove the pegboard and put in insulation that way. However, our blown-in insulation had some sort of adhesive agent added to it so it sticks together and doesn't settle. This approach might also reduce the mess if you ever removed some of the peg board in the future.
   / Blow-in insulation behind pegboard? #7  
If you want to breathe that stuff for the rest of your life, or at least until the particle-induced lung cancer puts you into hospice, go right ahead..

I think blown-in insulation and lots of square yards of small holes sounds like a very effective way to make sure you have plenty of dust in the air of your shop at all times. Short of using some kind of mechanism to feed it into a fan, I can't think of a better way to seed your lungs with bad stuff every minute you are in there.
   / Blow-in insulation behind pegboard? #8  
Attic Cat doesn't have a smell to it, it doesn't itch and when I'm blowing it into an attic, I don't have to wear a mask. It's really nice stuff to work with. Home Depot rents the machine for free if you buy ten bags, and the cost of it is the same as the smelly, itchy stuff. One bag costs more then the other stuff, but it goes so much farther that the price becomes the same.

Do you have enough attic insulation? If you are doing the walls, be sure to max out your attic. Around here, we shoot for R60, which is almost two feet of blown in insulation.

How much condensation do you get inside your walls? How much air infiltration do you get through the walls?

If it's not much, then go for it.
   / Blow-in insulation behind pegboard?
  • Thread Starter
OK do't want dust - cellulose is OUT. Good thing I didn't buy anything yet, the cellulose was $140 compared to $220 for the AttiCat. So what about the fiberglas Owens-Corning AttiCat? They claim it never loses it's loft.

I probed the ceiling with a wire and it seems to be insulated, and the roof is flat (new torchdown). I think the exterior sheathing is T111.
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   / Blow-in insulation behind pegboard? #10  
If you do the insulation project wrong enough,, and something happens,,
you void your homeowners insurance,

Skip the insulation, buy a propane IR heater, and for the couple days a week,
simply add the extra heat.

The cost will be less,, you will be safer, State Farm Insurance will smile,,, :thumbsup: