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need crawl space access

We have a 1950s house with an addition built on cement block over a crawl space. We've had the house two years. The room is carpeted, and we cannot find any access to the crawl space. We've looked in the closet, room corners, and all around the outside. We need to access the space to repair the H/AC ducts, and to insulate the space. The floor joists are on 16 inch centers.

How can we create an access so we can do the work? Can we cut a floor joist? Thanks.

Re: need crawl space access

Try to find an unobtrusive corner of the carpeted floor where you can cut say a 5' X 3' hole.

Try to score the carpeting beforehand so that a trap door can be constructed with the saved piece of carpeting/flooring.

If you have to cut a joist, it has to be reinforced with a cross- member.

Thus when the trap door is open, you shoud see 4 facing pieces of lumber, boxing in the hole.

The only alternative is to go thru the masonry block outside; this can be done with a rented chipping/demolition hammer (Home Depot); but then you would have to fashion a small door that won't look out of

Some specialty lumber yards carry such items; it's worth a call.

Re: need crawl space access

You'll need more than just a "crossmember"
You'll need to fashion a header, with joist hangers for the cut joists, additional joists to double up the joist on at least one end if the opposite one bears on the foundation and your trap door.

Re: need crawl space access

If the opening in the floor is within 3' of bearing & less the 4' wide both the header & joist can be single members per the international residential code. By my interpretation, you could probably put a 32" opening in the corner of a room where the joists bear without adding extra floor joists.

Getting extra floor joists in the crawl space shouldn't be that hard if there are crawl space vents you can remove. I would look for an unobtrusive place to put the hatch, but be willing to change locations depending on what the floor structure is doing.

Cutting a hole in the flooring, but not through a joist would be my first step. Then I would crawl between the joists to scope out the situation, the whole time ready to do battle with spiders & cobwebs.:eek:

Cutting a hole in the block & putting in a access panel might be easier.

Pretty unusual in my experience not to have a access to a crawl space.

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