I’ve heard of “crown up” when it comes to floor joists, but one of the joists in our hallway took the advice to an extreme. This 8-ft. 2×10 joist bowed upward 1/2-in. above its neighboring joists. The condition was bad enough to cause a hump in the floor, along with an annoying squeak.
My initial impulse was to yank out the bad joist and replace it with a straight one. But then I would have had to deal with the wall-to-wall carpet. Fortunately, my father-in-law came up with a good solution.
As shown in the drawing, I bolted a length of angle iron across the bowed joist and its two closest neighbors. The steel rail, called an elevator rail around here, is T-shaped in section. The vertical leg of the T is 4-1/2 in., while the horizontal cross of the T is 5-1/2 in.
I secured the rail to the bowed joist with a pair of 3/8-in. by 8-in. lag bolts. I predrilled the holes for the bolts, and then I tightened them slowly to keep from shearing the joist. I took out 1/4 in. of bow the first week, then the rest of the hump in the second week. The fix to the bowed joist worked to perfection.
—Tony Lindner, Lexington, SC
Edited and illustrated by Charles Miller
From Fine Homebuilding #92