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Hello all. Been asked by a client to insulate the crawlspace in their home that was damaged by Sandy here in Jersey. Some facts--the CS is ventilated with new concrete floor. Joist to be insulated are 2x12 I-joist 16 oc. Insulation is really no longer part of my repertoire but they insist that I do it since they were burned by quite a few BS contractors since the storm--that's happening a lot here. Anyhow, my plan of attack was to use unfaced R30 held in place with lightning rods which is what I would have done years ago in a vented CS. Now I'm hearing to only use faced insulation. Is this really becoming the norm? I've used unfaced insulation many times in this application including my own home without any moisture issues. Am I hearing wrong? Thanks
 

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Hello all. Been asked by a client to insulate the crawlspace in their home that was damaged by Sandy here in Jersey. Some facts--the CS is ventilated with new concrete floor. Joist to be insulated are 2x12 I-joist 16 oc. Insulation is really no longer part of my repertoire but they insist that I do it since they were burned by quite a few BS contractors since the storm--that's happening a lot here. Anyhow, my plan of attack was to use unfaced R30 held in place with lightning rods which is what I would have done years ago in a vented CS. Now I'm hearing to only use faced insulation. Is this really becoming the norm? I've used unfaced insulation many times in this application including my own home without any moisture issues. Am I hearing wrong? Thanks
Always install the insulation with the vapor retarder toward the warm side which is the floor.

What is a lightning rod? Some use nylon banding from insulation packs, some use metal insulation supports, but in most cases wire works just fine and they already sell it precut just for that.
 

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Yeah, paper up without a doubt. I was just wondering what's with all the must use paper in a crawlspace now? BTW, "lightning rods"--the metal rods that pinch in between the joist to hold up insulation--is what an old timer I worked with used to call them years ago.
 

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Or chicken wire
 
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diplomat
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In colder environments you still need to insulate the joists. Fairbanks Alaska average soil temp is around freezing. Best new crawls have insulated perimeters and joists. Or really fancy might be an insulated slab, but then you might as well just build slab on grade.
 

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the spray foam and closed vent procedure is great as long as any flooding doesn't happen again. If there is any problems in the future, it can accelerate and magnify the problems. I have eye witnessed this. Ohio does not have these problems, I know. Also, the price tag often hurts with that type of system installed.

OP contact me if you'd like. I reside in the direct sandy effected area, and can answer any questions you might have.
 

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even w/ kraft up, I wouldn't consider b/c of the condensation effect in moist spaces. Also, if it's a moist space, no to the metal rods b/c in time they will rust and when condensation gathers on the insulation, its weight will make it fall-all depends on THAT space.

I've wondered about insulating the joists w/ FG then installing 1/2" foil board on the bottom of joists and taping seams. Never heard of anyone doing it, but thought it might be a good method. I don't like the chicken (nylon) mesh only b/c the center of the heavy insulation bows downward-that would potentially create a pocket of air at the top. For that, rods are best, hmmmm
 

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Sean
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Unfaced is fine, but if you do use faced (or the inspector requires it) it needs to be installed towards the warm space i.e. the house. Fortunately the codes are finally being fixed to match reality & with the exception of a few real cold locations the using kraft faced FG or other vapor retarder/barrier is going bye-bye.

With that, was the slab insulated? if so then definitely go with a closed & insulated crawl

72 - best if foam is at bottom of joists & radiant pointing down (though I would save the cost on radiant) - fill with cellulose... As for a space at top, not really an issue in reality if you went with FG though some inspectors might not allow it based on not knowing any better
 

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I guess different environments are different, but in the cold crawls I'm used to, kraft up stays dry, kraft down gets wet. Moisture is driven away from the warm size and condenses on the cold side, so kraft down means condensation happens inside the fiberglass at the kraft face.
 

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Critters love to make their homes in fg, too..
 
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