Can a floor joist be "patched up"?

Question

Or do you have to put in a brand new one?

The joist is rotting due to water leaking through the bathroom floorboards. Has this took years to rot? Will I have to replace the joist fully?

Answer 1

You can sandwich it between a span of 2 timber members to bridge over the defective part. Just be sure that the new timber can perform to the same load together as the old joist, and that there is sufficient overlaps between the old and the new.

Also, check why the old joist has become defective. If it's dry rot or any form of infestation, the best thing to do is to get professional advice. You may even need to just replace the whole thing plus anything else that is infested.

Answer 2

Splicing Floor Joists

Answer 3

You should be able to "patch" the joist, if you can make sure you take out all the rotted wood and make sure the connections you use for the new pieces to the old have as much strength or more then the existing piece did. That probably means having metal bracing at the joints. Can't really get any more specific without seeing your joists. Be sure to use temporary supports around the repair area.

Answer 4

As long as you dont need to cut more than a third off the end you can splice it, m10 nuts and bolts staggered at 400mm centreswith a min of 75mm from edge of joists clearence .You would also need to overlap new timbers at least a metre beyond the damaged area of the joist.
If timber is suffering from Wet rot it will dry out naturally if you have stopped water leak, if Dry rot that a different matter and timber should be checked by expert to confirm extent of damage.

Answer 5

I recently seen a great method, if your talking about a cracked joist which is weak, first-jack up the sag in the joist. you can then liquid nail 2 pcs. of 1/2" ply on both sides of the area a few feet in each direction past the crack, then screw into the joist to tightly sandwich. After the glue dries remove the jack, this was amazingly stable and strong. Get back to me if you have any questions

Answer 6

yes, use 12mm threaded bar and 2 inch square washers.

The joist should be sandwiched between 2 pieces of timber, equal to the original and bolt right through the 3 pieces of wood at 400mm intervals.

A lot of older joints will be considered too small by todays standards so if you have space to make then 200 x 50 mm then do that

If the joist is rotten then soak it in wood hardener to halt the progress of the rot.

Once you've exposed the beam, its only a couple of hours in total.

I like your screen name, YA does feel like that sometimes doesn't it ?

Answer 7

the right thing to do is to replace it but an alternative would be to "sister" it with a new piece you would do this by cutting a new joist longer than the rotted section, or if you can expose entire old joist cut new one to same lenght, then just lag new joist to the old one making sure the lags go into solid good wood

Answer 8

It's cool if it's unique, but a lot of the time it's just something that's been done before. Or it's half a big gesture, like he tried to do something special to seem cool but was afraid to get too crazy. If you're going to do it, then do it all the way! Also, when it's a big promposal in front of a bunch of people, I imagine it would be a lot of pressure to say yes, which is unfair. Most importantly, it depends on the person your asking's personality. Would they really want to be asked the way that you're thinking of? If not, then don't do it - you're only thinking about yourself(trying to show off to other people). I personally would hate a public promposal, but a personal one away from other people might be nice. Don't go over the top if that person doesn't like over the top.

Answer 9

If the old timber has dry rot you will see "filia spreading across it and onto the brickwork. This looks a bit like fine roots and is how the rot spreads. If so you will need to cut away all the infected timber and treat the remaining and the new piece with Cuprinol or similar timber preserver. You should also treat the surrounding brickwork with rot killer for masonery. Be thorough. Earlier answers cover joining the new piece.

Answer 10

Sure just make sure you overlap the "patched in" length by as much as possible but say at least 1/2 foot at each end. Then fix through both lengths with some coach bolts or large bolt and nuts (pref stainless steel).