Do you have wood rot happening at your home? It’s a very common problem, and it’s getting worse each year, in my opinion, because new lumber is more susceptible to rot, and many tradespeople are not coating the fresh-cut ends of wood with paint or preservative. As you might expect, clever alternative products have appeared in the marketplace to take wood rot off your plate. I’ll discuss those in a moment.
Wood rot is a sibling of mold growth. Mold growth requires but three things: a food source, mold spores and water. Those three things are almost always available in and outside your home.
Wood fibers, and especially the soft, light-colored spring wood, is the food source for wood rot. Fungus spores are simple organisms that are abundant around your home. Rainfall, moisture in the soil and even water vapor in humid climates allow the fungi to start to munch on the wood in and around your home.
Rot is more common with exterior wood than interior simply because water falling from the sky sustains the fungi that’s eating away at the wood. Wood rot happens indoors only when you allow interior wood to get wet and stay wet.
Don’t mistake dry rot for some other issue. Dry rot is just wood rot but the rot stopped because the water supply was cut off. The fungi stop growing once their water source disappears. The active wood rot destroyed the lignin that holds together the wood. This is why dry rot wood crumbles in your hand.
I had a wood rot issue at my own home a few years ago. The builder used cheap exterior wood trim to frame around all my windows and exterior doors. Water cascading down from my roof splashed up and onto the vertical trim on each side of my exterior doors on my upper deck.
I had several ways to deal with the problem. The least expensive method was to remove the destroyed wood and patch it with wood epoxy. This method works well for small areas of rot. You need to have a bit of hand-eye coordination to make an expert repair, as you have to apply the sticky epoxy compound much like you’d apply drywall joint compound to a wall. The issue is that the wood epoxy has the consistency of peanut butter. It’s also very sticky and difficult to tool!
I decided the easiest thing to do was to cut off the bottom 9 inches of the wood trim. I then place new plastic trim that was the identical size of the original wood trim. My new plastic trim will never rot.
I used a vibrating multi-tool to cut out the old trim. I made a jig that has a 45-degree-angle cut to act as a cutting guide. I didn’t want a flat seam where the new trim met the old trim. I wanted a sloped seam so water would not flow back behind the trim. The flat surface of the multi-tool blade resting on the sloped jig made this a very simple task.
I then applied two coats of exterior paint to this angled upwards sloping cut of the wood trim. This paint would help prevent future wood rot by not allowing water to get to the wood fibers. I made an opposite 45-cut on the new plastic trim and slid it into position.
The moist soil caused the dense oak to start to rot. Fortunately, this rot is somewhat shallow and it only extends into the oak about 1.5 inches. I feel the best way to make this repair is to carefully cut away the rot using several different power tools and a router with an extended bit.
I plan to cut away enough of the oak so that I can then replace it with a small length of a treated 2-by-4. I’ll use a piece that’s been graded for direct burial, as it has quite a bit of the chemical preservatives in it. I plan to coat the entire oak post with two coats of liquid copper naphthenate. I’ll be sure to coat the hollowed-out portion of the oak with at least three coats before I insert the 2-by-4 patch.
I’ll also apply two coats of the copper naphthenate to the other oak posts as a preventative measure. This product is easy to work with, and it allows you to do a fairly decent job of protecting wood. Copper is a natural biocide.
Plastic wood trim is available. The plastic house trim is white. You can paint this plastic trim, but you need to pay close attention to the recommendations of the manufacturer. The plastic has a very high expansion/contraction coefficient.
Painting the plastic with dark colors increases the amount of movement as it increases the amount of heat retained by the plastic. Most paints don’t have the adhesive strength to withstand this much movement. The paint may start to peel, and then you’ll have a real mess on your hands.
