One tip for repairing wood rot in an exterior wall is to probe damaged areas with a fine-pointed tool. Replace any wood that the probe penetrated to a depth of more than 1/8 inch or that shows obvious signs of water damage. Another tip for repairing exterior walls is to utilize an epoxy wood patch when repairing smaller areas.
The process of repairing an exterior wall consists of locating the cause and source of damage before exposing the wall frame and assessing materials to determine the extent of the damages. Remove boards that suffer from extensive rot whenever possible, and use a saw to cut out damaged sections of larger boards. Measure and cut replacement boards, ensuring they are the same thickness of the originals, and use framing nails to hold them in place. When replacing damaged boards, install brackets at the top and bottom of the exterior wall to provide additional support.
Replace the plaster, drywall or siding after replacing all damaged construction materials. Use drywall patching compound to float the seam around the repair before sanding and painting all surfaces to match the surrounding wall. Monitor the area closely for a few weeks to ensure no further signs of rot or water damage develop.