I have a floor joist that has gotten some water damage and the joist needs to be fixed. We had thoughts on going back to "good wood" and making a slice to the end but not sure how to do it should we do a board on each side of the existing joist? Or is there a a metal clamp like thing such as what you would put to hang trusses. is there something like that or should we kill it with screws?
Go back and look at your post, makes little since to me.
A picture would sure have been helpful.
Most often it's best to sister a full length new joist using constrution adhesive and carrage bolts.
Just a patch will do little good.
Has the problum been corrected that caused it to rot?
...the joist needs to be fixed.
...going back to good wood and making a splice...
...a board on each side of the existing joist?
...metal clamp like thing such as what you would put to hang trusses
New wood on one side or the other should be plenty.
If you have access to some sheet steel... then sandwich a piece between.
Pay special attention that the new joist is well supported at the end.
Nail it thoroughly and a couple of carriage bolts won't hurt either.