Of heavy stoves and bouncy floors
Over the past few weeks I’ve slowly been noticing that the kitchen floor is a bit bouncier than I’m comfortable with. Particularly near the 400-pound stove.
The stove sits atop three 2x8 joists that run a span of about 14 feet. The center of these three joists is cut short, and is attached to a cross piece between the outer two joists. Effectively, the outer two joists are carrying the entire load for this part of the floor. This was all done so that the new boiler’s vent pipe could travel through the joist bay unobstructed by the middle joist. At the time I didn’t consider that the weakened joist structure plus a heavy stove might equate to a bouncy floor.
I don’t have a lot of options here. The room below is our laundry/boiler room, and the ceiling is quite low. Ideally I would run a beam down the center of the room, perpendicular to the joists, to brace them all. The only way this will work is if I can find some sort of low profile steel I beam, because anything more than 4” deep and I’ll be knocking my head while doing the laundry. I don’t think a beam made out of 2x4’s or a 4x4 would be stiff enough. (Unfortunately I also cannot cut the joists and put a beam inline with them – there are too many gas/water lines running through the joist bays.)
The other option is to brace the three joists directly beneath the stove. One problem with this is that our horizontal water tank (4’x2’x2’) sits on the floor beneath the stove in the basement. I can’t brace directly beneath the stove, but I can brace on either side of it, and I tried this tonight using some 4x4’s and my 2 bottle jacks.
This worked pretty well. The stove area is no longer bouncy. There is one other bouncy area out in the middle of the floor, which I think I can solve in much the same way.
For a permanent solution I’m thinking of using a couple of screw-jacks. I don’t know where to get these, however –HD doesn’t carry them. Does anyone know where to buy screw jacks and/or steel posts? I guess I’ll try a more traditional lumber yard.
5 Comments
Greg·December 12, 2005
Lolly columns might be better (and cheaper) than screw jacks. A lolly column is a concrete filled steel pipe (4-inch?). They come with steel plates that they sit on. I think the concrete keeps it from rusting on the inside. Use the screw jack to raise the floor a hair and then set it down on the lolly column. You will need a big pipe cutter (just like the “C” shaped cutters to cut copper, only bigger) to cut it to length. I’m sure you can rent one.
Derek·December 12, 2005
Our Home Depot up in Vancouver has screw jacks, I bought 2 there. Our 2x8 floors seem bouncy, even without a 400 pound stove. I guess you can’t sister the joists? I know I would have a hard time doing that, with all the wiring and plumbing going through ours.
Afterburner Al·December 12, 2005
Good luck on a final solution…firming up my Milwaukee house’s 1st floor with the Micro-Lam (/) raised the floor enough that the toilet popped off its mounts…but…the floor doesn’t squeak anymore.
Tom·January 16, 2009
The easiset solution to fix this would be to use a blocking type product called IBS. It is manufactured to fit between any space and depth of joist. You do not have to worry about the wires and pipes. It is very easy to install. Another possible solution for you.
Mick·March 3, 2009
Sorry, I know this may come too late since the first post in 2005, but just wanted to second the opinion of Tom, who talked about the IBS. Finished a retro-fit this past Fall with this bridging system - not too much needed had a relatively short span. But there is a large kitchen island that indirectly made the other floors in the area squeak etc. Sistering joists, putting in a beam-forget it. Too much hassle too pricey. I put one row of IBS in spent 1 1/2 hrs. doing it, paid about $90.00 (Cdn.) No brainer…