The Rot Doctor


Subject: Bridge Repair
Date: Sun, 23 Aug 1998

Dr. Rot,
Have used your products in the past with great success on T1-11 siding and window trim in my all wood house. New Problem:

I have a large foot bridge with 3 12x8 beams to support it (about 30 feet long). I've found rot on the ends of the beams. Some of the ends are pretty bad. The beams are placed on footings edgewise. The bottom of the beams seem in OK shape, but the top of the end is gone about 1/2 to 2/3 down.

*) I assume best procedure is to remove any "loose" rot until, say, a wire brush wont take any more off (even though still weak wood) and then drill 1/4" holes into top of beams and use penetrating stuff until it wont take any more. Then use your filler to restore the end of the beam. Would you agree? Which filler should I use for this?

If best procedure, how far apart would you recommend drilling the 1/4" holes? And down the center of the beam only, or stagger them as they are 8" wide beams?

The rest I need to do is covered in your deck section.

Thanks for your help and great products!

Dave L.

Thanks for the complimentary words about our products!

Your suggested approach is correct. Since you'll be working from above, you have gravity working for you, pulling the CPES down into the wood. I would drill the access holes in a staggered pattern, and since it's apparently so simple about 3-4 inches apart. Fill them with the CPES until they'll accept no more, as well as brushing the CPES generously on the surface, give it 4-5 days for the carrier solvents to evaporate away, and then come back with our Epoxy Filler to re-build. The filler will bond with the CPES-soaked wood and you'll have a strong structure.

If there are any interior voids you're not certain you can get to with the Epoxy Filler, then flooding in some of the Layup & Laminating Resin is the answer. It has a 24 hour cure time.

When you drill, make sure there are a series of access holes near the outer edge of the rot area. What you want to do is make sure the CPES gets to the good wood/bad wood interface. This will encapsulate the fungi that it encounters and help resist further rot problems.

Come back if you have more questions.