the other day I pulled down a ceiling in a basement to give easy access for the new plumbing going into a bathroom above. Much to my amazement I notice a double joist is cut in half to allow for 4 inch PVC to run RIGHT THROUGH it. This is about 4 feet from the exterior wall and 6 feet from the other end. The other end is the opening in the floor for the stairs, the double joist is attached to the stair opening on a joist hanger.
Edit: to clarify, the “hole” isnt through the joist, rather the pipe runs up and down and the plumber, or whoever, decided the joist was in his way so he cut the joist out. the joist comes off the wall about 4 feet, then there is a “gap” cut out the entire depth of the joist so the ends of the cut are just hanging there with no support. On the other side of the pipe the joist goes about 6 feet to the stair case opening where it is attached with hangers. I beleive the only thing holding the joist in place is the nails comeing down through the sub floor
My question is what is the best way to fix this?
I’ve thought of several options
1) Put in new joists on either side of the one that has been cut.
2) sister a new joists to the existing one on the side that the pipe does not stick out.
3) Use a heavy gauge steel plate to rejoin the two pieces, not sure on what gauge and how long it would need to be? If this is the best option would carriage bolts be the way to attach it or something else?
4) move the plumbing and install new joist, which really is not an option.
5) what ever suggestions you guys can up with that may be better then my own?
Thanks In advance
Edited 1/10/2003 10:58:27 PM ET by CAG
Replies
Cag,
Number two.
Professor,
Thanks for the quick responce,
that was my first thought but since the orginal one was doubuled up I didnt know if sistering one onto the side would be enough?
Cag,
Use two of them.
# 3 w/ 1/4 x 4" plate
Jim,
the gap is about 4.5-5 inches, do you mean a plate 4 inches wide extending past the end of the of the cut, how far on either side of the cut should the metal extend, or should I use a plate 1/4" * 9" X? ,
the joists are 2*10
Thanks for your input
i would use 1/4" plate as wide as I could fit above / below the pipe...I felt that you only had about 4" of joist left. as for length.... I would at least 3' on either side of cut, maybe 4'. Clean/ degrease plate, predrill, glue & screw. stager your screws every 6". top row on 12" centers starting at 3" from end. Bottom row on 12" centers starting 9" from end. this way, you have a screw every 6" all the way across. I would use ## 12 square drive pan head screws, or a hex head. lube w/ wax & long enough to get a good bite on all joists there.
hope this helps.
i get my plate at a local steel salvage yard. buy it by the pound. I do not see any reason why you need to span the width (9") of the whole joist....the cut out is the weak spot.
Jim, sorry, let me clarify the situation a little bit, its not just a 4 inch hole in the joist, there is a gap in the joist of 4 inches, the pipe runs up and down not through it. Who ever put in the pipe cut a gap in the joist the entire 9 1/4 inches.
Edited 1/10/2003 11:04:54 PM ET by CAG
What's the load on the doubled joist? How long since it was hacked? Any problems, or does it just make you nervous? Joe H
Joe,
Thanks for your interest and help,
The joist runs to the opening in the floor for the stairs down to basement. It is the first joist after you get down the stairs and runs across the opening. I cant say how long since it has been cut in two. The current home owners purchaced the home a few years ago and have done no plumbing or other renovation that could have caused this. The floor above is squeky and sprigy above it and it does make me nevrous.
I know little about framing and the fact they have what is essentially a 32" span instead of 16 kind of bothers me. To fix this wasnt in the contract my boss arranged but they seem willing to fix it, I would feel a lot better knowing that I didnt just ignore it.
As for the load, there doesnt seem to be anything bearing on it other then the usual.
Jim has you going in the right direction with the 1/4 plate. a suggestion is that 1/8 would be sufficient and your idea of bolts vs. screws is an easier/stronger way to go. Glue is always a good idea.
If this were my house, I'd use 3/16 plate about 3 ft long on both sides (that's 'cause I've got a stack of that size in the junkpile) and bolt it up with 20 ea 3/8 carriage bolts (again, 'cause that's what I got in the junk pile off old pallets) but regular bolts (e.g 16 ea 1/2 or 32 ea 1/4) or metric work as well. Match drill your steel to the exact size, drill the wood to a 1/32 size under and drive the bolts thru the wood for a tight fit. Waht works easy for this is predrill the steel, hold in place with a few drywall screws on the joist, and drill the wood using the stel plates as a template. The bolts should be in a line approximately 1 inch from the top and bottom of the joist, bolts at the centerline are a waste of bolts . This will provide the full original strength of the joists.
As you said, you have noticed springiness above, so put a post and hydraulic (0r car) jack below the beam before doing the above and jack the beam up (you need to 'feel' this - eg. you don't want to crack any plaster but be sure the floor above has no sag) Leave the post in place till any glue you have used has setup (polyester resin or boat epoxy works good in this application)
Is this a header? By that I mean are there other joists hanging from it around the stairs?If reality wants to get in touch, it knows where I am.
This is just one idea. Maybe you can shove a scrap into the top space too to resist the compressive forces.
Have fun kicking it around
Gotta run soon.
Excellence is its own reward!
Who ever put in the pipe cut a gap in the joist the entire 9 1/4 inches.
That changes things....I think i would shim out enough to sister a full 2x10 on it, or a 1/4" x 6" plate w/ at least 3' on either end and attach as stated earler. Which ever you do, you should make sure all sag is out ...w/ a jack. I prefer hydraulic jack.
Jim thanks, I had planned on using a jack to get everything back where it should be.
Yes, I could do it this way, nothing in the way, but would it be strong enough?
Im concerned it would not have the same support as some of the other opitons. I would be relying on nails/screws/ and joist hangers to hold everything up. I guess its the same concept as the stair opening but again would it be strong enough?
Easiest for you in design effort may be to request Boss Hog to supply the part number and source of a couple of big 10 inch wide truss plates that go about 10" (or whatever boss says) beyond where the joists were cut. Glue a cuple pieces of good 1/2 plywood to one side of the joist (to provide clearance for the truss plates) and flatten the teeth where they would hit the pipe .
Pound a big truss plate onto each side of the joist and you are all done - steel plates & bolts would be cheaper (and maybe quicker) for me 'cause I likely have them in the junk pile and the drill press is always set up. Expect to spend more than a few minutes getting all the teeth fully embedded.
PS: I tried to do a quick fix like this on my brother-in-laws house a few years ago and could not find anything (not knowing the local suppliers) over 3" x 5" where he lives (NW Indiana) on a Saturday - which is why Boss can maybe suggest a source for you.
No, I won't spec a truss plate for that sort of repair, and for several reasons.
First, that's not what truss plates were made for. They aren't designed to span gaps without buckling.
Second, truss plates aren't made to be beaten in with a hammer. They're either pressed in hydraulically, or pressed in with huge 24" diameter rollers. Takes about 400 PSI or so to fully seat them.
Third, (almost) no one will sell the plates for uses other than trusses for liability reasons. I haven't sold a single one in the 18 years I've been in the business.
The drawing Qtrmeg made is the closest to what I'd recommend. But the size and species of the scab, and other details like connection sizes and locations would have to be designed by someone capable of analyzing the loads and such. I would never attempt that without looking at the actual job.Q: How does a man show that he is planning for the future?A: He buys two cases of beer.
Ron, Agree with all your points, I apologize to all for my use of "truss plate" terminology.
I probably should have said metal connections, recall having seen such some with upper and lower chord reinforcement bars (multiple spot welded to what looked like truss plates ) for gap spanning, but that may have been homemade stuff by an engineer<G?>. Are there any devices as described commercially available?
" Are there any devices as described commercially available?"
Never heard of anything like you describe.Q: What is the difference between men and government bonds?A: The bonds mature.
Thanks to everyone, everything is back up in place and the floor doesn't flex or squeak any more
Engineered with the right hangers or ledgers I expect it would be, but I am not an engineer.
W/ wflather's suggestion...use double joist hangers on the double joist, and single hangers on the headers. This may be your simplest solution....wish i had thought of it earlier.
No, that dbl joist that was cut is supporting the stairway header, not to mention the wall above. You have to sandwich the dbl joist, and most likely jack it up to do it. Pick steel or wood, either way will require the joist be built out so that the pipe doesn't stick out.
The pic is one thought. Green is the shim to bury the pipe, red is for the scabs. Glue and nail, bolt if you want.
Edited 1/11/2003 5:54:54 PM ET by Qtrmeg
CAG, which end of the stairs is this? Is there anything else holding this up? Does it tie into something else on the other side of the opening? Is the staircase freestanding? Joe H
Joe is the "down Stairs" portion of the stairs, the stair stringers are hung on the other side of the opening. As far as I can tell the only thing left holding this up is where it is attached on either end and the nails coming through sub floor into it keep it from coming complety down now. There were 1x3s on the flat to hold the old tile cieling up those have been removed to allow access for the pluming. Its being temporary held up with just enough support to keep it from coming down until monday morning. Its probably been there for years.
My question is the hell is stupid enough to cut through an entire double joist?
Guess they don't teach gravity in plumbing school.
Thanks for the reply, I think that sounds like best idea to sister a new joist on each side of the old. Carry them the full length of the span correct?
Thanks to everyone else that has replied all advice is appreciated
That cut joist was originally doubled to be the carrier for the header along the long side of the stair opening. That header is also norally doubled and the remaining single joists are hung to that.
As it is now, the carrier no longer supports the load as was intended and if it weren't for the interaction of the other components, such as the flooring nailed to the joists, the lumber box around the stair opening, the other carrier at the other end of the opening, the structure would have a pronounced downward sag.
You can use Qtrmeg's drawing as a guide but instead of scabbing on another short joist, dying into the header, add another full length joist out board of the originals (next to the one already drawn by Qrtmeg). Both of these new joists should bear on whatever the cut originals were on. You can now attach, as in scab on, the cut joists to the new, using the bolts as was mentioned by, I think, Junkhound. Place at least 2 bolts, high and low, near the point where the header was attached to the original carrier and a couple more further away toward the plumbing cut. That should be more than enough to transfer the weight from the cut carrier to the new doubled carrier. Not knowing the full lengths of all the parts makes it difficut to postulate further.
What the heck, throw in a couple more bolts.
That won't work. Go back and look at his orginal diagram.
The joist just to the bottom of the cut double is only supported by the joist for the stair opening. And that inturn is surported by the cut joist.
ooops, missed that.
Qtrmeg is right. That Joist is supporting the stairway framing and, unless there is a bearing wall under the frame at least half of the floor load on the joists tying into the stairway. Again, unless there is a bearing wall under the frame I would expect you have significant sag in that area. You say you are not a framing expert. I would recommend you get someone who is, perhaps even a structural engineer. All of the problems should be corrected.