Not every rotten piece of wood can — or should — be repaired. Readily available trim elements that are easily removable (such as brick mold and fascia boards) are simply not worth the time and materials to fix unless the damage is minimal. Strong candidates for epoxy repair include expensive components like porch and stair parts, hard-to-remove elements like window sills, and historic pieces like moldings or turnings that would require custom replication.

As with an iceberg, the vast majority of rot damage is beneath the surface. Before you can decide whether repair is feasible, you must determine the extent of the decay. I start with a painter’s 5-in-1 tool, carving into the loose, punky decay as if I were cleaning out a pumpkin. After I reach sound wood — it may be discolored but should be...

or Register to read the full article.