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
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
can you use something like a red-i-post temporarily on the first floor
to jack the joist up and then sister it and cripple it to reinforce? I
would think that crippling at a minimum would be advisable if you're
going to reinstall a heavy chandelier. Also use a ceiling fan box to
mount the chandelier and reinforce it well while you have the opportunity.
replace "roosters" with "cox" to reply.
Have you considered securing a 2 x 8 to the side of the sagging joist
and using the now level joist to secure your flooring to? If the fact
that the 16 inch on center would no longer exist for that joist could be
tolerated, that might be an easy way to go.
On Jan 19, 2:40 pm, email@example.com wrote:
You could straighten it by taking heavy 2" heavy angle iron, drill
holes every foot, take 1/2" coarse thread lag bolts, pre drill the
wood with maybe 1/4" drill and tighten them down over a few days. it
hopefully wont crack but sister another piece along side. If the hight
is to high with the angle iron plane the beam a bit.
Get a 2x2 of appropriate length. Screw down on the bowed joist with
3" construction screws. Snap a chalk line on the side of the 2x2 that
is in plane with the rest of the joists. Unscrew the 2x2 and rip
along the chalk line with a skilsaw. Glue and screw it to the top of
the offending joist.
Don't think the chandelier caused the joist to sag, some upon drying do tend
to crown extremely, sometime down as you have, and as one in my house did,
it went up creating a hump in the floor.
If the ceiling is drywall, you would be better to remove a 4 foot strip
along the joist so that you can examine the whole joist. A plumber at some
time may have hacked away all the strength when he was working in the area,
at least you can then see what perforations there are in the joist. I would
not leave it as it is as you will notice it from below every time you walk
by. Fix it by sistering another joist, maybe one size smaller on each side
if vertical clearance is a problem and cutting the old joist to push it up.
Only by opening up the ceiling can you know what you can fit in there, and
what pipes are in the way and may need moving either permanently or
temporarily. While reno-ing the bathroom this is the time to fix it all.
This happens to me all the time, a relatively simple job snowballs into a
major change in multiple areas.
To estimate the time it takes to do a task: estimate the time you
think it should take, multiply by two and change the unit of measure
to the next highest unit. Thus, we allocate two days for a one hour
On Jan 19, 3:40 pm, firstname.lastname@example.org wrote:
I think you would get best results from Ken's approach. Attaching a
straight joist of the longest possible length to the existing joist
would provide enough extra strength to support the chandelier as well
as provide a solid level surface for the sub floor.
The sagging joist is probably the result of 'creep' resulting from the
unplanned for weight of the light.
Deforming the sagging joist without cracking it would take a period of
weeks at least.
On Jan 19, 5:54 pm, email@example.com wrote:
Am I the only one wondering what the ceiling below looks like? If
the one joist sagged by an inch, one would think the ceiling below
would be an obvious mess. And it wasn't caused by the chandelier
below, at least assuming it's of the weight class found in typical
Before I went with some type of sistering solution, I'd make sure the
ceiling below is OK. You don't want to sister it only to find out
that the ceiling has an obvious sag spot too.
On Jan 19, 1:40 pm, firstname.lastname@example.org wrote:
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.
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