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Ceiling Insulation for existing steel building

TTMotorsports

Red Skull Member
Joined
Jan 7, 2021
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3315
Messages
1,289
Loc
Lucerne Valley, CA
Ok so my new home has a 30x80 x 12' eve steel building on it already. The purlins are 2" square box tubing. The walls I insulated with fiberglass matt and drywalled it. No the ceiling has a ridge vent since it is cooled by a large swap cooler. BUT the ceiling being metal it gets very hot with sun beating down on in all day. The shop is loaded up with all my tools, equipment and vehicles so I can't unload it and do spray foam insulation. I need the full 12' height, possibly 14' would be ideal so I can put my 12' tall pallet racks in easily.


Now I am thinking about going up 2 purlins and running a steel stud from side to side, approx 20' length and support it from the roof up heigher to prevent sagging on them at all. Then putting a ridge cap on the building instead of a vent, which won't be an issue since there is a large exhaust vent fan on opposite wall from swap cooler at other end of the shop. Remounting the LED lights on new drywalled ceiling. Then doing blown in insulation to approx 4" thick on that to provide insulation from above now. I will lose the light from the skylights but that's not a problem with the quality led lights I have. Going up 2 purlins will allow me to put an angle on the drywall above the swamp cooler and exhaust fan on other end wall.


Does this sound like a feasible plan or do you guys have a better idea? Thanks


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as goofy as it sounds i ran plastic across my shop and created the same air gab your thinking up and has made my metal building alot more bearable in the heat and winter too. cheap enough to do and would provide instant relief you could work one bay at time and no die at least.
 
We just put up RadiantBarrier in our shop, found it on Amazon, works great. Used HVAC silver ducting tape to hold it up. You can see it in this pic, its that tinfoil looking stuff, its got about 1.5" air gap between it and the roof paneling


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If you're going to use a radiant barrier it should have an air gap, think bubble wrap and two sided. Much mo betta
That would need to be pressure washed before being sprayed so yeh, thats out. Too bad because 1-2" of closed cell would work great
 
Ok so if I add the radiant barrier to the bottom of the purlins I will have a 2" air gap between that and the roof. Isn't that good or should I try something else?
 
Ok that stuff would be awesome but enough for a 30x80 shop with a 3:12 pitch roof would make me go broke. I found a company online that sells something similar. 3000 sq ft for $550 shipped. Just hard to spend that kind of money without knowing for sure that it'll work good
 
Ok that stuff would be awesome but enough for a 30x80 shop with a 3:12 pitch roof would make me go broke. I found a company online that sells something similar. 3000 sq ft for $550 shipped. Just hard to spend that kind of money without knowing for sure that it'll work good
what product did you find?
 
you nearby a city?
Call around and see if you can get old cubicle panels, they're always free, and they're 2" rigid fiberglass insulation board in there. They use it for sound insulation, but it is just as good for thermal insulation, and it is rigid so it doesn't drape down.

Tear them apart and scrap the frame, some are extruded aluminum which is reasonable money when you get it free of anything magnetic.
If you're worried about fire, just tear the fabric off, too.
 
I'm in the high desert Lucerne Valley near Hesperia Victorville apple valley and not too far from inland empire of LA area.

What kind of places would I call around to find something like that?
 
I'm in the high desert Lucerne Valley near Hesperia Victorville apple valley and not too far from inland empire of LA area.

What kind of places would I call around to find something like that?
any office furniture surplus places on craigslist?
Used pallet racking guy I know always turns them away, he'll take desks and such but the dividers he can't manage to sell.
 
if you do blown in on a flat ceiling and don't suppy attic venting you will get mold or condensation issues. so you either need to fill the whole attic with insulation to the ridge so there is no air flow or provide attic venting. or just insulate the vaulted ceiling and retain the gable vent
 
I know this won't be the ideal answer given the criteria in first post...
Move everything to one side of shop... spray foam open 1/2. Move everything to other side of shop... spray foam that half. Move everything back in place.
Take the pain one time...
 
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I know this won't be the ideal answer given the criteria in first post...
Move everything to one side of shop... spray foam open 1/2. Move everything to other side of shop... spray foam that have. Move everything back in place.
Take the pain one time...
that's what I'd do honestly. some big stuff just cover it.
 
I've gotten quotes for spray foam from a couple companies and paying 8K for that doesn't make sense for what I want to do here. Anyone suggest DIY spray foam kits I could do myself?
 
even hanging a barrier between like a giant tarp off each bean will keep an air barrier between you and the hot ass roof tin.. we did that in all of our military tents and it does help. its not insulation but will cut down on some of the heat.
 
Ok so if I add the radiant barrier to the bottom of the purlins I will have a 2" air gap between that and the roof. Isn't that good or should I try something else?
Thats not enough for the stated R value but much better than no gap.

We used foil faced 2" eps board on my father in laws shop. Ran steel banding from the eave to the ridge in the gaps of the highs. With the eps boards in place pull the banding tight and run a tek screw through it into the purlin.
Made a huge difference in radiant heat load.
 
This "system" seems to achieve the desired outcome.
Air sealed inner envelope, foil barrier to block radiant heat.

 
I don't really need much insulation. Even last summer when it was in the 90's the swamp cooler kept shop down in the high 70s/low 80s. But if the swamp cooler wasn't on I could feel the heat radiating down from the roof. Also my clock up on the wall about 2' down from ceiling reads temp and it's usually 7-10 deg hotter than working at could level. So just needing something to keep the heat on roof or at the roof. Also the birds love the vented ridge cap and like to make nests on all my main beams. So i'm planning on capping that to keep the dirt/birds out of the shop. I can't find a metal roof supplier that sells ridge caps that would work for my building/sheet metal style. How do you guys suggest that I cap the edges of the ridge cap to keep the birds and dirt out?
 
Thats not enough for the stated R value but much better than no gap.

We used foil faced 2" eps board on my father in laws shop. Ran steel banding from the eave to the ridge in the gaps of the highs. With the eps boards in place pull the banding tight and run a tek screw through it into the purlin.
Made a huge difference in radiant heat load.

I'd like to do that as well but my shop is 50x80 and i'm not wanting to spend $4000+ on something that just helps a little bit
 
I'd like to do that as well but my shop is 50x80 and i'm not wanting to spend $4000+ on something that just helps a little bit
In my testing a 4x8 1/2" piece of foil backed EPS makes a huge difference in A/B testing and its $11/sheet, cheap enough to test with.

Leaning one of these sheets against my uninsulated roll up door completely blocks the radiant heat when the sun is direct on the door from the east.
Buy one and try it out.
 
I know this won't be the ideal answer given the criteria in first post...
Move everything to one side of shop... spray foam open 1/2. Move everything to other side of shop... spray foam that half. Move everything back in place.
Take the pain one time...
Big fan of spray foam. Did a pole barn last fall in it. Building did not get below 32 degrees all winter. Even when it was sub zero for a week.
 
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