How to Repair Rotted Wood in 6 Steps
Save your wood, save your wallet
- Putty knife
- Wood chisel
- Screwdriver
- Drill (optional)
- Safety goggles and gloves
- Wood filler
- Epoxy wood hardener
- Sandpaper
- Primer or paint (optional)
Rotted wood is a common issue in homes, especially in areas exposed to moisture, such as windowsills and door frames. If left untreated, wood rot can compromise your home's structural integrity and appearance, leading to costly repairs. If you're up to the task, savvy DIY homeowners can learn how to repair rotted wood and save some money rather than hiring a professional.
How to Repair Rotted Wood
Repairing rotted wood can be time-consuming depending on the extent of damage. Here’s what you’ll need to do.
Inspect the Damage
Photo: Mel Stoutsenberger / Adobe StockUsing a screwdriver, inspect the area to determine the extent of the damage. Gently poke the area with the tool; if it's soft or spongy, it indicates rot damage. If more than 30% to 40% of the piece of wood is rotted, replacing it would be a better option than repairing it.
Clean the Area
Clean the area thoroughly to remove dirt, debris, and loose paint to fully expose the rotted wood. Ensure the area is properly ventilated before working and wear protective gear.
Remove the Rotted Wood
Photo: soupstock / Adobe StockUse a wood chisel or putty knife to cut out all the rotted wood. Remove any soft or discolored material until only solid wood is left behind. If the extent of the rotted wood is deeper, you can use a drill to remove it.
Treat the Remaining Wood
Apply a wood hardener to the solid wood surrounding the damaged area to stabilize and strengthen it. Allow the hardener to cure per the manufacturer's instructions.
Fill the Damaged Area
Photo: lassi meony / iStock / Getty Images Plus / Getty ImagesPrepare the epoxy wood filler according to the package instructions. Use a putty knife to apply the filler, slightly overfilling the area to allow for sanding. Let the epoxy cure completely. Depending on the product, this can take a few hours to overnight.
Sand and Smooth
Use medium-grit sandpaper to smooth the filler. For a seamless surface, you can finish it off with fine-grit sandpaper. After sanding, sweep away any debris and clean the area before applying primer or paint.
DIY vs. Hiring a Pro
Repairing rotted wood is a manageable DIY project if you have basic carpentry skills and time to dedicate to the task. DIY repairs are suitable for small-scale damage or non-structural areas like window frames or trim. However, you should thoroughly remove all rot and use proper materials, as incomplete repairs could lead to recurring issues.
For extensive damage or structural components such as beams or load-bearing posts, hiring a restoration professional is the better choice. Professionals bring expertise and can complete the job more quickly and efficiently. They can also ensure that repairs meet safety standards and are built to last. Expect to pay at least $500 on the cost of professional dry rot repair, though the average is $1,400. While the upfront cost of hiring a professional is higher, it can save time, prevent mistakes, and avoid the need for future repairs.
Sometimes, mold is the cause of rotted wood or could escalate to a mold issue if it's not repaired. If you do have a mold issue, hire a professional. The average mold remediation cost ranges between $1,200 and $3,700.
Frequently Asked Questions
Expanding foam isn't a good material for filling rotten wood. It lacks the structural strength and durability required for long-lasting repairs. The material may temporarily fill gaps, but it doesn't bond well to wood or provide the necessary support for load-bearing or exterior areas. Expanding foam is better suited for insulation purposes or sealing gaps.
Avoid using wood filler for structural repairs or areas with extensive damage. Wood filler is designed for cosmetic fixes like filling small holes, cracks, or surface imperfections, and it doesn't provide the strength needed for load-bearing repairs or large gaps. Wood filler also shouldn't be used in areas exposed to heavy moisture or extreme outdoor conditions unless it’s a product specifically rated for such environments. Wood replacement or a strong epoxy resin is a better solution for severe rot or structural damage.
Homeowner’s insurance coverage for dry rot depends on the rot's cause. Most policies exclude damage caused by gradual issues like poor maintenance or long-term exposure to moisture since you can stop dry rot. However, if the dry rot results from a sudden and accidental event, such as a burst pipe or storm damage, it may be covered. Review your policy or consult your insurance provider to understand your coverage and determine if dry rot repairs fall under your plan.
