Taking a slice off the top of a joist

Old house and a few things are quite bent! In articular, a joist along a corridor (about 15 feet long* has bowed up ward, making a hump in the floor. Building up the other joists running along here would throw the floor level out in terms of skirtings etc, so it would be good to be able to take say (I haven't measured accurately) 20mm-ish off this one to flatten the floor. I know that will weaken it and I would sister it with another timber to bring the strength back. So how could it be done? 20mm is too much to plane etc. I thought of putting a circular saw on its side and running it along but that doesn't look very feasible. Any suggestions chaps?

Reply to
GMM
Loading thread data ...

I'd have thought an electric plane would probably do the trick with the least amount of pain (hopefully it's not the full 15ft?!)

Otherwise - I don't know how load-bearing this is and how exposed it is, but could you remove it altogether and replace it with a straight one?

Is there any mileage in trying to bend it back to where it should be (using leverage against the adjacent joists somehow)?

David

Reply to
Lobster

GMM,

How long, wide a deep is the joist itself - (is the measurment you gave - the corridor or joist length)?

Taking 20mm off the top of the joist is not advisable, even if you are going to reinforce it - BTW, how are you going to fix the joists and support the ends of the reinforcing timbers?

How long, deep and wide are the reinforcing timbers going to be - and how do you intend to fix them to the existing joist and where are you going to drill the holes for the fixings (most imporantly, which part of the existing joist)?

And as harry has said, what about the ceiling (if any) fixed on the underside of the joist - type etc?

If you are going to the trouble of removing the floorboard the full length of the joist (and you will need to) to plane and reinforce it, why not simply replace it with a nice straight new one? After all, you've done all the hard work.

Cash

Reply to
Cash

could clamp/nail a couple of bits of straight planed wood on either side proud of the joist and run a router along the humped joist supported by the planed wood - obviously the amount proud would depend on the depth of cut set on the router .... assuming you are going to reinforce it .....

Reply to
Ghostrecon

Well I would cut several strips of ply the depth of the joist and screw + glue them on either side so the tops are at the finished height. Then I would get a hand saw and lie it across the ply and saw the top off. Stager the joints in the ply and use it as the reinforcement.

Reply to
dennis

It's rare for me to openly contradict another poster here, but with all due respects, I think you really are talking through your hat!

In this case, they reinforcing material should be bolted to the joist and should, at the very least be of equal thickness to the original (and *NOT* "several strips of ply") doh!

And as for advising the reducing any load bearing piece of timber without being told the size of it, its unsupported span and live and dead load carrying well...

Cash

Reply to
Cash

Well I didn't say how thick the ply is! You really shouldn't argue unless you know how thick the ply is, how long the ply is and what load is on the ply. I can assure you that three pieces of 18 mm ply on either side would replace

20 mm of a joist.

Well if you are that worried then its a lot better than taking 20 mm off and it will resist further warping. I suggest you lookup engineered joists to see just how strong they can be.

Reply to
dennis

Makes a change. Denboi usually talks through his arse.

Reply to
The Medway Handyman

Rather more than you I believe Dennis,

Isn't there, from my experience there is a huge difference between a properly engineered pywood joist and sticking a few bits of ply on the sided of a dimension (or even rough saw) timber joist.

What's so difficult in understanding gluing and screwing bits of ply onto the side of a joist?

I will accept that you said the depth, but out of curiosity where did you say "along the length of it" in your post (reproduced here)?

---------------------------------------------- "Well I would cut several strips of ply the depth of the joist and screw + glue them on either side so the tops are at the finished height. Then I would get a hand saw and lie it across the ply and saw the top off. Stager the joints in the ply and use it as the reinforcement." _____________________________

Where is the "top and bottom" of the repair that you suggested? You simply advocated fixing plywood to the sides - so can you show *ME* how your suggested repair corresponds to an engineered plywood "I-beam"?

Shame you can't apply the basic principles of asking for more relevant information about a job before shooting from the mouth.

As for applying them in 'the real world' I have - have you done so, or is it all theoretical with you via Google?

Now Dennis, it's interesting that you have not answered one of the technical questions that I have posed to you.

Cash

Reply to
Cash

Of all the posters to choose from you had to choose dennis:-)

Reply to
ARWadsworth

I like to live dangerously sometimes Adam - and that's about as dangerous as I can get these days. ROTFL

Cash

Reply to
Cash

Ignore them all, Dennis (as you do). Why change the habit of a lifetime, I for one, enjoy reading your tripe.

*choke* Ahhhh yessssssssss, Dennis, what an appropriate name.
Reply to
brass monkey

So you don't think the OP has even read what you posted then? If he has he already has all the knowledge you have posted so he will already know all about making sure its strong enough, etc.

Well I haven't even noticed you post any questions during your mouthing off.

Reply to
dennis

I agree; however, the removal of 150-odd lines of post would have made a helluva difference there, don't you agree?

Reply to
grimly4

And it's an old property, probably even more over engineered as they didn't have the skills to cut everything to the bone like we do today.

MBQ

Reply to
Man at B&Q

If the OP has, then I'm sure that he can make up his own mind - if he hasn't then that doesn't cause me any problem.

Try re-reading the last but one post I made - you know, the one that you selectively edited.

Never mind Dennis, life still goes on. LOL

Cash

Reply to
Cash

Yep, the old Mosquito really was some aircraft wasn't it - but what the hell that has to do with cutting of a floor joist really escapes me.

Typical youngsters (and Dennis), can never seem to keep to the subject at hand.

Cash

Reply to
Cash

Depends on size of the timber, length of the timber, live load, dead load etc, and generally you would be right - but what about the unexpected?

But the one the one question that has yet to be asked - is why has a (presumably old) joist bowed nearly one inch upwards for no apparent reason (in a presumably) short time. Surely that reason has to be found before any remedial works can be suggested?

Just out of curiosity though, how can you base your decision on a job that you have never seen and with the minimal information given - you and Dennis must have second-sight Harry

Cash

Reply to
Cash

We don't have second sight unlike you, however all we have done is suggest ways the OP could fix the problem. It is up to the OP to decide how as only the OP has all the details and what his skills are. All you have done is get the wrong ideas about what was said.

Reply to
dennis

You're welcome GMM.

If you go ahead and decide to cut the joist, have you thought of using a very sharp axe, cutting with the grain to 'knock' most of the waste off - and then finish off to the correct height using the electric planer or even a sharp hand plane?

Just to perhaps cause a little more controversy with one or two here - if you could get hold of an old adze, that would be even better, as you could stand up and do the job, and with a sharp tool and a little bit of practice, get an almost plane-like finish for a lot-less effort.

Just wear a pair of steel toecapped shoes and shin-pads though while you're learning. :-)

All the best with a bugger of a job, and let us know how you get on.

Cash

Reply to
Cash

HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.