I’m rebuilding a house after tearing it down to the bare studs. I found a few spots where (in the bathroom) the floor joist had gotten soaked through and rotted. This is how I fixed them. The house is over a hundred years old, and had surprisingly little rot. This house originally did not HAVE a bathroom attached to it, and the previous owners did a very slapdash job on adding one in. So not only am I dealing with the wear and tear of time, but also shoddy workmanship. Making it so that this house lasts another hundred years is my goal. :)
2 x 6 board. size and length varies
quick setting wood glue
3 1/2" wood screws (length can vary depending on wood size)
flat head screwdriver
electric/ battery operated driver
elbow grease and patience
Step 1: Find the nasty spot
Find the rotten spots. This can be easy or difficult. You can poke the questionable board with a screwdriver and see if there’s any give to the board, and you can also do a visual inspection: a darker spot on the board can be a sign of rot.
Step 2: Get rid of the rotten spot
Cut the rotten spot out. This part can be a little hard, depending on what wood you are working with. Pressure treated stuff won’t let the water flow through the wood as well as straight regular wood. You want to cut about 6 inches past where the rot ends, just to make sure no more moisture will get through. Once that’s done, your spot will look like the picture above. The floor joist was also where a wall is, so there were two joists butted together. MAKE SURE that the other board is not rotted as well! I checked all four sides of the other joist to make sure there was no rot.