Look for cracking or pealing stain
Look for black mold or green mold, it should be removed as soon as possible to reduce damage to logs
Look for fading or failing stain or clear coat
Inspect checks (cracks) if they are filled with caulk.Any little cracks must be filled to avoid water from getting in behind the caulk.It cannot dry out fast enough to avoid damaging the logs.It is better to leave the checks open so that the log can dry out.They check (crack) in the first place because it is natures way to dry out the log.
Inspect chink or caulk for cracks or breaks
If there is to be new stain put on a house that has failed, the best thing to do is strip it back to bare wood.Stripping the house is done by either corn blasting or sandblasting.It depends on how old and how much stain and paint is on the logs.
Sometimes the blasting process does not clean the logs.At this point we can sand the logs to clean all the material left on the logs from blasting.It also gives a smoother finish to the wood.Some people prefer this to the pitted look and feel of corn or sand blasted wood.
At this point we recommend putting a borate treatment on the logs.This helps slow boring bugs and log rot.It can only be applied to bare wood. There are borate rods that can be stuck into drilled holes in the log, but they are really only good for spot treating plus the holes have to be plugged.
Staining is next.This is strictly up to customers taste in color, but the darker you use the longer the stain will last.Most log home stains are applied with two coats of color and a coat of clear on top.The clear coat should be maintained with a fresh coat every three years.
Chinking is typically the last step, but can be applied before staining. Most older log structures have mortar chinking.This should be covered with the new latex chink that has some flexibility to it compared to the hard mortar, which is always broken away from the logs allowing water and bugs into the interior of the home. Sometimes a small portion of the old chink has to be removed before installation of the new chink.On new construction the process is the same except a foam backer is used instead of the old chink.
In regard to rain gutters, they should be checked for leaking in the down spouts, especially if they are tight into the corners.Irecommend that the down spouts be mounted out away from the house as much as possible.
You should budget about $1.50 per square foot of living space / per year for professional maintenance.