Subject: Home projects questions
Date: Sat, 30 May 1998

I have a couple of potential home applications for your products. One involves the plywood decking beneath a ceramic tile floor on my covered, screened deck. I have some rot of the plywood flooring around the outside edges of the ceramic tile along two walls. This is because water which blew through the screens and onto the floor seeped around the edges of the floor and eventually rotted the plywood for ~ 3 to 4 inches. The rest of the plywood floor is sound. My plan was to remove the wood trim around the sides which are rotted and seal the edges with silicon rubber. I am wondering if your products can be used to "fix" the rot before I do this. There is no structural problem with the floor but from the bottom surface (there is finished bedroom beneath this floor) the rotted flooring is visible. I have minimized any future water entry into the room but want to avoid tearing up the outer 2 rows of ceramic and rebuilding the plywood. Can I use your products to strengthen the plywood rot from the top and perhaps from the bottom (access from the ceiling of the bedroom below)?

Yes, remove the trim around the outside of the plywood, make sure the rotted portion of the plywood is reasonably dry (we have used commercial kerosene heaters to dry wood when necessary), and the brush/inject all the rotted areas with the Clear Penetrating Epoxy sealer (CPES). The CPES penetrates very well into plywood, and should wick through the damaged wood without difficulty. As our Test Section on the web site demonstrates, the CPES will wick a long way in porous wood, which of course includes rotten wood. Additionally, you can go below into the bedroom and brush on the CPES where the damaged ply is visible. Cover the floor, because using this stuff on overheads can get messy. As we say, when mixed it has the consistency of diesel fuel. Give it 3-4 days for the carrier solvents to evaporate and the epoxy to cure and you're ready to put things back together. You might also want to coat the trim pieces with the CPES if it's salvagable and you plan to replace with trim.

DO NOT use silicone rubber! If you use a flexible sealant, use a polyurethane based sealant. It will bond with the CPES-impregnated wood and keep water out. Silicone won't. The poly sealant we always recommend is the 3-M 4200 (lightly adhesive) or the 3-M 5200 (strongly adhesive). But there are other poly sealants around and any of them will work just fine.

My second potential application is some weathered cedar siding on my exposed garage wall. I have tried several epoxy fillers and latex putty but they all either pull away or pop out of the cedar as the wood flexes from the hot/cold weather changes. Most of the cedar is sound but there are some areas which need to be filled, sealed and sanded. I cannot get any of the previous filler/sealer materials to last longer than a year before it turns ugly. I am trying to avoid completely replacing the cedar siding.

Well, what's happening here is that the epoxy filler and the latex putty is just sitting on top of the wood. There is no bonding. The wood soaked with the CPES and then filled with a good epoxy putty such as our Fill-It (or polyurethane sealant, like the 3-M products) will stay there almost certainly. This is a bit of a trickly situation, because everything depends on how much the wood is expanding/contracting. You could end up with the CPES/putty staying in place but the wood splitting away somewhere else. I'd suggest here that if you decide to use the CPES, you also buy a little putty and do a test patch somewhere and see what happens through a season. If everything works, then you can go ahead and complete the project. If not, then you're going to have to investigate some hi-powered wood treatment systems to see if you can stabilize the cedar. You should probably look into this anyway after the repairs. As you may or may not know, CONSUMER REPORTS is now into a multi-year study of surface wood treatment products and has already stated that some simply do not work at all. Perhaps a check at the library into CONSUMER REPORTS can be of help to you down the road.

Let me know what you can do. If you need to discuss this with me, let me know. I can call you instead.

Regards,
Jim T.

Jim, feel free to call if you need better clarification. I am almost always in the office Mon-Fri from 6:30 am to 5:30 pm Pacific time. Be happy to talk with you. Or come back via e-mail if you have additional questions.

Our products are available only through us. We always have them in stock and we ship Monday - Friday (except holidays) within 24 hours. GA is about 2 days away via UPS. Hard to say how much CPES you might need, because everything depends on how much the wood absorbs. You do want to give it all it will take. I would probably recommend starting with our 2-gallon unit. The CPES will keep if the tops are screwed back on the cans. VISA, MASTERCARD and AMEX cheerfully accepted.

Doc