Clean the logs by sweeping off all dust and debris. Use a garden hose with a pressure nozzle to wash down the logs from top to bottom. It is easier to recognize damage to the log home when the logs are clean and dry. Inspect the structure for signs of active insect infestation and moisture damage. Examine the logs from top to bottom and under the eves, decks, attics and crawl space. Look for fine sawdust, boring holes in the logs and mold or mildew stains. Use colored-plastic tape to mark any areas of damage. If active insects are present, enlist the aid of a professional termite exterminator. Repair any moisture leaks.
Evaluate the extent of the damage. Minor damage does not require immediate repair, however any damage that weakens the structural integrity of the home must be addressed promptly.
Use a hammer and small chisel to chip away small areas of wood rot or insect damage. Cut away the damaged wood until sound and solid wood is exposed. Apply wood epoxy (following manufacturer's package application instructions) to fill in the damaged area. When dry, apply a petroleum-based wood preservative (shingle oil or a commercial log treatment product) to the area. Repair log caulking as required.
Remove and replace severely damaged logs. Logs requiring replacement should be matched using the same method and building style as the original structure. Cut out the damaged section of log with a saber saw that has a metal cutting blade. This type of blade will easily cut through spikes, screws or nails that may be anchoring the log in place. After cutting, use a pry bar to remove the log. Using a chain saw, cut and shape a new section of log to fit the area where the rotted log was removed. Attach in place with a metal plate and wood screws. Repair caulking.
Seal the new log with shingle oil. Apply with a wide brush or rag.