How to Repair Log Rot


log rotThe best strategy when treating wood rot is to remove the rotted areas. See the options below for repairing wood rot.

For logs with significant rot damage (50% or more):

 If a log on your home is more than 50% eaten away by rot, the structural integrity of the home has been compromised and it is important to move ahead with a plan to replace the rotted log. Make sure to contact an experienced log home renovation professional to replace a log.  A number of such professionals can be found on the Find a Contractor section of LogFinish.com.

If you just have the beginnings  of a log rot problem (i.e. a soft spot in the log) consider the below treatments:

1. Remove, Protect and Replace

  • Make a vertical cut on either side of the soft spot to the depth of the soft wood.  
  • Then use a coal or vibrating chisel and hog out the rotted wood until you reach solid  sound wood.   
  • Level out the area to a flat surface.  
  • Coat the area with Shellguard RTU (borate) to prevent further expansion of rot.
  • Allow the Shellguard to dry for 3-5 days.  
  • Using a piece of log siding or a section of whole  log cut to the depth of the hole, cut a segment to precisely fill the gap.
  • Fasten the section in place with Liquid Nail and caulk all edges with Energy Seal. Apply  Shellguard RTU and then the wood finish you have selected.  
  • As water is usually the cause of rot issues, make sure that the source of the water problem gets solved.

2. Use a Epoxy system developed specifically for wood like the M-Balm and E- Wood epoxy system:

  • Following the steps listed above to hog out the rotted wood.
  • When you get to solid wood, coat the area with Shellguard RTU (borate).
  • Allow the Shellguard to dry for 3-5 days and then re-coat the area with M-Balm. M- Balm is a 2 part epoxy primer. This prepares the area to accept the E-Wood Filler.
  • Fill the primed area with E-Wood and shape to the log profile. The epoxy filler will be stronger than the original wood.
  • Sand the area and apply finish.
    • Please note: The E-Wood has little absorbency and must be used in conjunction with film forming finishes such as Lifeline Ultra 2  or Ultra 7 ,  Sikkens Log & Siding or WeatherSeal.  Penetrating products such as Q8 Log Oil and Seal Once Poly Blend  do not work well in this situation. E-Wood has a wood tone but it may not match your homes exterior wood tone. Use multiple stain coats to minimize any blotchiness and spotting.

Article authored by Bill Frykberg, LogFinish.com