Log Home Restoration: Cleaned & Stained?

I often get requests from log home owners saying, “I want to have my log home cleaned and stained.” When I ask exactly what do they mean, I usually here, “I want the logs power washed and re-coated.” At this point I ask for a few minutes of their time to explain log home restoration.

Depending on the type of finish on the logs and it’s condition will dictate what process must be used to prepare the wood for re-coat. This is where log home restoration can sometimes get a bad name because of the contractor either not knowing the proper steps to be taken or just not caring.

The general rule of thumb is, if you have a latex stain or paint that is in GOOD condition, then probably a good wash with a chlorine/detergent solution will do. If it is failing, media blasting using cob, soda or glass is the best form of removal. If it is an oil stain, there are two factors to take into consideration. Is it a “film forming” or a “non-film forming” finish.  Knowing this will determine what process must be taken to prepare the logs for recoating.  

As a log home restoration contractor, I have been called to many log homes that have been stained (with an oil or latex stain) only a few years prior and are now failing. As a rule, the problem with the stain is one of two things.

First, the stain was put on a newly constructed home that probably had “green” or wet logs and were not properly cleaned and prepared to receive the finish. Second, someone came along and sold the homeowner on a bleach wash and a fast re-coat. 

With the first, the newly constructed home, several things must be taken into consideration. Most of the time with the exception of a few log home manufactures that have kiln dried logs, most logs probably have not been cut down very long and are still “green”. If it is a milled log, it is most likely coated with “Mill Glaze”; a result of the logs passing through the fast turning milling knives that leaves a film on the surface of the wood. Also, it is not uncommon after the home is built to find soiled, stained or mildewed logs that have been erected. So you end up with wet logs that have a film of sap on them and stand a good chance of being dirty. Not the ideal surface for a penetrating stain or any kind of finish for that matter. 

In the second case, it must be determined if the stain is a “film forming” or a “non-film forming stain. If it is a film forming stain, the best advice is to follow the manufacture’s directions for re-coating. Take note that most film forming oil stains require “clean bare wood” to re-coat which means a total strip of the old finish. Often the instructions can be confusing or unclear so read carefully or call the manufacture to get clarification. Many people including contractors ignore this important step and apply another coat of stain on top of the existing stain. The problem with a “film-forming finish, is the new coat can not penetrate the film of the existing finish and therefore remains on the surface. The logs will look good for a while but, because it did not penetrate and it was applied on top of an already failing stain, it will certainly fail prematurely. 

With “non-film forming stains, because there is no film, the finish not only will not peel, crack or blister, it simply wears away. Depending on the age and condition, usually a light chlorine and TSP solution wash is sufficient if the wood was cleaned and prepped properly the first time. However, if it can not be determined  that the wood was properly cleaned, it would be best to spend the extra money and do it right, rather than having a new finish fail prematurely. Proper preparation of the wood is imperative to achieve maximum performance of any finish. 

 It is generally accepted that while bleach will kill mildew, it has no cleaning properties. So if the house (or deck) is mildewed only, it may be alright to use bleach to remove it, but that does little to remove dirt and other debris. The best way to solve all of the above problems is to do a “light” strip unless there is an intact stain that must be removed, in which case a more aggressive strip would be required. 

Although there are “mill glaze” remover products sold, a light chemical strip is all that is needed to not only remove mill glaze, but also dirt, stains and discolorations. Stripping will also remove mildew however, it is recommended to follow up with a chlorine rinse to make sure all the mildew is not just removed, but the mildew spores are killed deep into the pores of the wood. If not completely eradicated from the wood, mildew can grow back under the new stain causing major problems that can only be corrected by going through the whole stripping process again. 

The stripping process is rather involved and costly. However, if the existing finish is failing, it is the proper way to prepare the wood. If the new stain has to be removed because of shortcuts, it will end up costing far more than if it had been done properly the first time.

So when the log homeowner wants their home “cleaned and stained,” they need to be sure that the proper procedure is being used for their particular situation. Each project is different and an on site inspection is required to determine exactly what is needed.