I have a lot of damaged wood caused by powderpost beetles. I can see their exit holes and the powder is falling out of most. Do I need to replace this beam where they have been causing all the damage? They only seem to be in the one beam ( I think they call it a floor joist) but I’ll get it fixed if needed.
Powderpost beetles can do a lot of damage if given the chance. In most cases, they’re not detected till something significant has been discovered so whats happened is fairly common. Also, it’s not uncommon for their activity to be limited to one piece of wood. In other words, they could be in just that one piece (and hopefully so). That being said, the first order would be to treat the wood with activity, along with all the other accessible areas, to insure the problem is not more wide spread and that if it is, the damage won’t get worse.
Once the area has been treated with something like the Boracare we have listed in our powderpost beetle control article, it would be wise to get a knowledgeable expert to inspect the floor joist to see what needs to be done. In most cases, “sistering” or attaching another joist to the damaged one will do the job. Leaving the old one in place would be fine and probably best; the new one would then take on the weight of the structure and the old one would be left to support what it can.