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JGarvin
Floor insulation

When my house was built it had an attached garage. As a lot of people do I removed the garage door and framed it in. I am getting ready to raise the floor up even with the floor in the rest of the house for more efficient heating because the concrete lets off a lot of cold air in the winter. My question is, do I need to insulate the raised floor or will that make the floor sweat when the concrete below it is cold and the air in the house is warm causing mold or other problems?

Thank You for any possible help.

Timothy Miller
Re: Floor insulation

Howdy, need more information. are you raising the floor level of the garage a inch or feet? it makes a difference. in other words more information. if you are installing a sub floor remember no wood touches concrete. for starters. depending on how much room there is in raising the floor there are choices in insulation....

JGarvin
Re: Floor insulation

I will be raising my floor approximately 11 inches but the floor joists will only be a few inches off the concrete. I hope that will help with the answer I need.

Thank You for the reply

keith3267
Re: Floor insulation

Place a heavy duty plastic vapor barrier directly on the concrete, build the floor joists and insulate between them, then put down the flooring.

JGarvin
Re: Floor insulation
keith3267 wrote:

Place a heavy duty plastic vapor barrier directly on the concrete, build the floor joists and insulate between them, then put down the flooring.

Thank You very much for the info. That will help a lot knowing what to do for sure before I do it. Thanks again Have a wonderful day...

Fencepost
Re: Floor insulation
keith3267 wrote:

Place a heavy duty plastic vapor barrier directly on the concrete, build the floor joists and insulate between them, then put down the flooring.

Also install vents to the outside from this crawlspace. Even though you've installed a vapor barrier -- it will block most of the moisture -- some will still infiltrate the crawlspace and if it's not vented you will have mold and rot problems.

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