Home>Discussions>INSULATION & HVAC>Insulating crawl space between 1st and 2nd floor
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Karl
Insulating crawl space between 1st and 2nd floor
Karl

We've been rehabbing our 1930's 4-square house since we moved in here in Western New York State (we get plenty of winter). As part of that process, I've lowered the ceiling from 10 feet to 8 feet in the bathroom and will be in the adjoining laundry room (they're both side rooms and it didn't make sense to me to heat the extra cubic feet). As this essentially creates a 2 foot crawl space between the 1st and 2nd floors, this does bring up 2 questions:

1) Should I be insulating the ceilings of both rooms (and could it be roll insulation) since the crawl space is not heated?

2) Both have an exterior wall, I plan on using fiberglass batts with a vapor barrier between the studs. Can I leave the paper facing exposed above the ceiling or am I supposed to enclose that with wallboard too?

HandyAndyInMtAiry
Re: Insulating crawl space between 1st and 2nd floor
HandyAndyInMtAiry

You should not insulate that area. Heat rises and you will want that heat that is rising thru to the second floor. That is the way the floor is heated.

I am assuming that you have plaster walls. If you do, do not bother removing that to try and gain an insulation R-Value in only 4 inches of vertical space. The plaster wall gives you more that insulation and sheetrock will give. Another plus to this is that mold will not grow on plaster. Just caulk around the windows and ensure there are no cracks or holes that have been missed. Fill them with foam or caulk. You do not want to use a vapor barrier in the stud bays, these houses were designed to breathe and not be air tight. This keeps the mold from growing, and keeps the structurecool in the summer.

Handy Andy In Mt Airy NC

Andrew

Clarence
Re: Insulating crawl space between 1st and 2nd floor
Clarence
HandyAndyInMtAiry wrote:

You should not insulate that area. Heat rises and you will want that heat that is rising thru to the second floor. That is the way the floor is heated.

I am assuming that you have plaster walls. If you do, do not bother removing that to try and gain an insulation R-Value in only 4 inches of vertical space. The plaster wall gives you more that insulation and sheetrock will give. Another plus to this is that mold will not grow on plaster. Just caulk around the windows and ensure there are no cracks or holes that have been missed. Fill them with foam or caulk. You do not want to use a vapor barrier in the stud bays, these houses were designed to breathe and not be air tight. This keeps the mold from growing, and keeps the structurecool in the summer.

Handy Andy In Mt Airy NC

Andrew

Plaster has 0 insulating value.

Plaster will retain Heat / Cold but does not add or subtract insulating value.

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