On Jan 19, 1:40*pm, wrote:
I am a novice DIYer who is renovating a second floor bathroom. I
removed the subfloor to move some pipes and now that I am ready to
relay the subfloor I have discovered that one of the joists ( which
are 16 inches apart) and which is in the centre of the room has sagged
an inch. It has sagged where the first floor chandalier was attached.
I removed the chandalier and tried to pull up on the joist but it
won't budge.I am limited as to how much I can push up on the joist
from the first floor because I dont want to disturb the finished
ceiling.

When I lay plywood across the joists there is an inch gap between the
plywood and the one joist. I could proceed and screw the plywood down
and then use a levelling mortar to fill the trough, or I could place
shims *on the top of the 2x10 joist so that the plywood would lay
flat.What would be a good material to use as a shim? or how would an
expert proceed?
Brent
Thanks

Thanks for all of the suggestions.I think I am going to bolt a 2x8 to
the side of the existing joist and lay my subfloor on that.The house
is 30 years old and I think a chandalier pulling on the joist in one
focused area just caused the joist to warp over time.The ceiling below
is a white and has a popcorn finish and unless you are looking very
hard you dont notice a sag.I never noticed the old floor sagging or
moving--I guess the old subfloor just bridged across the gap.