How to Repair Dry Rot Yourself

dry rot in a home
  • 1-2 hours
  • Beginner
  • 40-80
What You'll Need
Medium-width paint brush
Wood stabilizer
Wood filler
Putty knife
Heavy-duty rubber work gloves

Dry rot repair is crucial to preventing more damage to the infected wood. Dry rot is wood decay caused by a type of fungus that typically thrives with very little moisture. Common areas infected with dry rot are window sills, shutters, and roof run-offs. It can also be found in wooden outdoor furniture such as picnic tables and Adirondack chairs. Dry rot repair must be completed to prevent the spread of the fungus which will completely destroy the piece of infected wood.

Step 1 - Prepare the Work Location

Choose a warm dry day to complete any dry rot repair. You'll likely have to complete the repairs outdoors, so it's important to make sure the weather is warm and dry to allow the stabilizer and filler to dry.

Avoid making the repairs on a humid day, even if the temperature is warm. Work in a clean, well-ventilated area and make sure you have a place to dispose of the infected wood immediately. Dry rot is caused by a fungus, and you don't want to spread the fungus when you're doing the repair. Wear gloves and other appropriate safety gear because most brands of wood stabilizer and wood filler are toxic.

Step 2 - Remove the Infected Wood

dry rot on wood

Use a saw or a chisel to remove the dry rot. It's crucial to remove every last piece of the infected wood when completing dry rot repair because even a few strains of fungus-infected wood could re-infect the healthy wood and cause more damage. If you notice the problem soon enough, the damaged area will likely be small and manageable. You'll be able to remove the dry rot by chipping away at it with a chisel. If a saw is required, use caution so that you don't cut so much wood away that you can't salvage the piece. Allow the rest of the wood to dry completely.

Step 3 - Treat the Uninfected Wood

Apply an even layer of wood stabilizer to the good wood that was exposed to the dry rot. A medium-width paint brush will work well in most cases, but use a larger or smaller one as you need. The stabilizer has a glue-like consistency, so it will destroy the brush. Use a clean old paint brush that you know for sure hasn't been exposed to any fungi, or buy a cheap one at your local hardware store. Allow the stabilizer to completely dry for several hours.

Step 4 - Apply Wood Filler

Check to make sure the wood stabilizer has completely dried. Mix the wood filler, making sure the substance is thoroughly stirred. Apply a thin even layer of filler over the wood which was treated with the stabilizer. Allow it to partially dry and then apply another layer. Repeat as necessary. Too thick of a coat applied the first time may not bond. Remove any extra filler before it dries because hard filler can be difficult to sand.