4 posts / 0 new
Last post
adding joists

We have an old Key West home (pier construction) with joists that are 2"X 5 1/4"(real size Dade pine)spaced about 24" apart.They are notched to fit the sills about 4 1/2 inches. I would like to add joists between them - they would be 1/2 the width of the house and rest on the center beam. However fitting anything with a 18 inch craw space is a problem without major surgery. I am wondering if I could use a kind of sandwich consisting of a 2x4 at the center and 1x6's on each side.

Any help would be appreciated

Re: adding joists

There are a couple of options here. One is to shave the ends of each new beam so that they are are about 1/2 to 3/4" shorter than the height between the sill and the sub floor on one end and between the center beam and sub floor on the other. That will make it easy to install, then put a wedge between the sill and the joist and between the center beam and the joist. Pound the wedge in until the joist is supporting the floor.

You can also stiffen the floor up by putting beams running parallel with the center beam about half way between the center beam and the rim joist. That will cut the span of the joists in half. This would be my preferred option.

You could also just sister to the existing joists. You could use 1x one each side or a 2x on one side only.

You can fill in between the joists with blocking on each end, flush with the inside edge of the rim joist and with the edges of the center beam and then use joist hangers.

Re: adding joists

Can you remove some siding and slide them in from the outside?

Re: adding joists

yes on on side fairly easily the other would be a hassle

Sponsored Stories

TV Listings

Find TV listings for This Old House and Ask This Old House in your area.