How to Repair Floor Joist Termite Damage

Lead Image
  • 4-20 hours
  • Beginner
  • 40-1,200
What You'll Need
A couple of 2-by-4 wooden floor joists
A hammer
Plenty of Nails

Are your floor joists in danger from termites? If they are and the damage is very minimal, you may be able to do the repairs yourself. You can save yourself a lot of money by doing the work yourself. Making repairs like this is quite a job. There won’t be much in the way of supplies that you would need. Time will be the biggest factor here. If this is your first attempt at repairing a floor joist with termite damage, you might consider having a friend who knows how to do work like this to come to lend you a hand. There are some steps to follow that will hopefully get you going in the right direction.


You will need to look for the damaged area that will need to be repaired. Once you find it, remove any of the top floorboards above the damaged area to look at the subfloor. Then you must attempt the repairs from the crawl space or basement so that you can save the interior flooring. You will also need to be able to see the damaged area well enough from underneath it to be able to fix it properly.

Disconnect Utilities

You will now need to disconnect your utilities temporarily because you could run into some wires near the damaged area. If they are live wires, you could get electrocuted. Be sure to clear all the wires away from the area if there are any.

Placing the New 2-by-4

Now that you have the utilities cut off, you can set the new 2-by-4. Place it as close to the termite damaged one as possible. You need to secure it by nailing it to the crossbeam on the base of the floor. This will help to provide the structural support needed for the damaged beam. Then you can remove the damaged portion and replace it with a good sturdy wooden beam.

Extra Tips

Removing termite infested lumber from your floor without replacing any kind of support: you might do some significant damage to the foundation and put yourself as well as others in harm’s way. If you don’t know what to do or you are unsure, seek the help of a professional.

Now that you have learned how to replace a termite-infested floor joist, you can see that it is not an easy job. One way to be sure that you can prevent this kind of situation is to have your home termite treated. A once a year inspection can save you from having to tear up your floors to repair the damage that could have been prevented. Should you ever have to tackle a job like this, Ask for help, and play it safe? It might also be a good idea to get the opinion and advice from a professional. They will be able to give you the best advice possible.