How to Combat Rotting Trim

October 14, 2015

Trim is found all over the exterior of most houses. It’s installed at corners, along roof lines, above and below doors and windows, adding a decorative flair to any home. The type varies depending on your home and the sort of exterior wall construction your home uses. However, most trim boards are 1 by 6 inches or 1 by 4 inches.

Trim is used for two reasons. It is aesthetically pleasing, typically painted to accent the wall paint. It also reduces moisture infiltration which is great for the house. However, all the moisture stays on the trim. This leads to rot and if the rotten trim isn’t replaced, the rot can reach the house.

How to Combat Rotting Trim


First, you’ll need to inspect the trim to see if it is rotting. To do that, you’ll need to check all over the trim, especially the top, bottom, and edges. This is where water and moisture are most likely to enter the wood. Check the roof facing trim at the corners and tops of the boards and in the case of door and window trim frames, check for rot a the top and bottom.

Second, if you do spy rot and you’re going to DIY it, you’ll need to purchase new lumber to replace any rotted boards with. You’ll need to make sure to match the type, thickness, and texture of the old boards as closely as possible. Prime the the new trim with a primer paint. The primer paint will seal the wood making it harder for moisture to sink into it.

Third, you’ll need to remove the rotted boards. To do this you’ll need a pry bar and a hammer. But the pry bar in between the trim and the house siding and lift until you feel the nail loosen themselves. Once that happens, remove the nails with the hammer. Take off entire trim pieces, even if only part of the trim has rot.

Wood Rot Under Wrapping 2

Fourth, after you’ve removed the trim you’ll need to check the underlying exterior siding and framing to make sure that the rot hasn’t spread. If it has spread to framing, you’ll need to call a professional. If it hasn’t spread, then you can seal any exteriors with primer and house paint (if they haven’t yet been sealed). If you see any cracks or splits or gaps, this would be an excellent time to take care of them. Fill cracks or splits with wood filler and caulk any gaps you may see. Gaps between the siding and the frame can hold water and damage the frame of the house.

Lastly, you’ll need to install the new trim boards. Nail the trim to the siding, making sure to overlap the boards. The face of one board should cover the edge of another. If you’re doing trim along the eaves of a roof, nail the horizontal trim to the rafter or subfascia, depending on how your roof is set up. Install a new metal drip edge on top of the roof fascia if there isn’t one already installed. If there is already one installed check it for gaps or rust – if those are there you’ll need to remove it and install a new one.

If you want to repair your trim, rather than replace it entirely, there is a way to do that, although in most cases it is better to replace the trim entirely. You’ll need to cut off the part of the trim that is rotted. Then you’ll need to choose a piece of wood. Make sure this piece of wood is measured and fits the area perfectly. A tight fit is necessary to avoid more moisture damage. Apply the glue after dampening the clean surfaces. Then drill small holes into the replacement trim. You’ll then need to attach it to the area with long screws that you have driven to just below the surface of the wood. And if the glue seeps out of the area, use sandpaper to sand it down. Cover the screws you installed with putty and then paint the wood to whatever color the rest of the trim is.

Know that rotted trim can happen to any home at any age. Just make sure to have the trim repaired or removed before the situation reaches the frame of the house.
Accord Construction is available to help you through the roofing process, no matter what you need. If you’re worried that the rotten trim could mean something more, we can inspect your roof for any possible issues. Our company is fully licensed and certified and ready to help you deal with any roofing issues. We are the best choice for professional roofing in Oklahoma City and Edmond, Oklahoma. No matter what you need, we want to help you achieve the roof you want. Call us at (405) 302-5520 to learn more or to arrange a consultation.

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