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Crawlspace stud wall insulation and covering question

Crawlspace stud wall insulation and covering question


  #1  
Old 01-24-22, 10:08 PM
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Crawlspace stud wall insulation and covering question

Best way to insulate this crawlspace exterior wall? Wall is roughly 10 feet long and 30" high. This is in the borderline of climate zones 5&6 in MI. Currently a dirt floor, but looking to get some plastic over it at some point.


Have the same wall just a little ways down(mechanical room where all the wires are coming from) that I would like to remove exisiting covering-its not drywall..old 50's-60s wood paper board stuff..and the insulation and airseal things up and insulate and board. Same line of attack?
THanks!
 
  #2  
Old 01-25-22, 12:02 AM
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So that is a fully un-insulated crawl with exposed exterior walls? Floors must be cold as hell, especially with the cold snap were having right now!

Best insulation would be foam. Would greatly help with air sealing and insulation.
 
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Old 01-25-22, 12:13 AM
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Correcto on cold floors. This is a 'summer home' and this is our first winter with it and thankfully dont spend alot of time there yet. Finding lots of things to attack as far as weatherizing. I agree on the foam, but I cant leave that exposed can I?
 
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Old 01-25-22, 06:11 AM
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Foam in the crawl space isn't "exposed" as it's inside and protected from UV (sunlight). Spray would be the best but perhaps too good. Rigid foam sheets can be cut to size and would be much less expensive and could be easily removed in the future if needed.

Do you have wood eating insects in your area; termites, carpenter ants...? If so I would check the house's insecticide treatment history. If termites are common in your area I would make sure the house is treated before foaming the foundation walls. Termites can bore tunnels through the insulation and the foam will conceal their mud tubes so it's best to treat to insure that you never have that problem.
 
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Old 01-25-22, 02:43 PM
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As that is wood siding with no sheathing, current thinking is caulking each bay for air seal, tar paper, rockwool, foam board on surface.
 
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Old 02-26-22, 02:41 PM
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Followup question, Have vented crawlspace for addition with insulated floor and hanging flexible heat ducts. Room above is too cold (warm in A/C season) and it seems like the ducts would perform better if their surroundings were warmer, Crawlspace floor and walls are concrete. Can I also insulate the walls? Research I have done says floor/wall insulation is one or the other, not both, Oh, and also ducts are drooping like wet noodles because trimming and dressing were poorly done. Am I correct in assuming there would be benefit in eliminating the droop so air doesn't take a roller-coaster ride?
 
  #7  
Old 02-26-22, 08:52 PM
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Yes, insulate walls or ceiling, not both. You insulate the ceiling if the space is open to the outside air and sealed from the house. You insulate the walls if you seal the space from the outside and open it to the conditioned air of the house. The latter is how you warm the floors above the space.
 
 

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