In situations where a surface is media blasted due to some type of paint failure and the hope is to create longevity in terms of how long the paint coating “lasts” WITHOUT peeling, there is a certain procedure that has to be followed in order to make sure that you give your paint coating as great a chance as possible to adhere for a long-time basis.
Those that have heard me preach on the subject before, understand how much of an advocate I am about integrating media blasting into the surface preparation process to help combat a paint peeling situation that is a bit pesky.
If you have a surface that simply does not seem to hold a paint product – white cedar shingles, “smooth-side-out” red cedar clapboard, pressure treated decking, etc. – and you would like to get your paint product to stick WITHOUT replacing the building material that the paint is applied to in its entirety, media blasting (assuming no lead paint is present) is an EXCELLENT beginning step!
What media blasting does is two-fold.
First, it removes the existing paint coatings that in many cases have built up to be quite thick overall, as the efforts to fix an often gradually worsening peeling issue lead to quite a bit of paint/stain coating buildup.
The other thing media blasting does is essentially alter the cellular structure of the wood surface itself as it opens up the pores of the wood and makes the surface SUPER receptive to receiving a paint coating where previously it either repelled the actual coatings applied or simply did not allow anything to penetrate its surfaces.
After the media blasting process, the first thing I recommend doing is to clean the surfaces being tended to with a softwash process that also includes a mildew/mold killing cleaning agent as part of the procedure.
The next thing we do is sand all the areas that have just been blasted in order to provide a more even surface ahead of the first coat of product application.
After the sanding, the first coat of product is applied (I recommend ALL product applications being done with a brush or roller and NOT simply just “sprayed”).
When coating white cedar or pressure treated surfaces with a solid stain, the first coat of solid stain is applied, a light sand to all included areas is then done as the first coat will raise the grain of the wood. After this is done, a second coat can be applied and you will be where you need to be in terms of completion.
If you are coating a surface that is either red cedar or the final coat is going to be a ‘paint’ product vs. a ‘stain’ product, the process is slightly different. Your first coat applied should be an oil primer, then a light sanding should occur (again, due to the wood grain rising in this process). After this, a second coat of the primer should be applied followed by two coats of finish.
With red cedar, the oil primer is utilized to neutralize any potential cedar bleed that may occur in the future. For surfaces receiving a “paint” coating as their finish, the oil primer sets a great stage for paint product application when it comes to sealing and allowing the finish product to stick or “bite” on larger areas of bare wood.
As you work through this process, there may be additional “normal” paint steps that are necessary – caulking/filling where necessary as an example as well as wood repairs that may have been uncovered after any coatings have been stripped.
Once this whole procedure has been completed, you will be simply amazed at the results.
A surface that may have previously not been able to hold a paint product for longer than 6 months, will now be able to have its paint or stain coating last indefinitely WITHOUT peeling and the next time the surface needs to be either painted or stained, will now be simply as a maintenance procedure to freshen up the coating and NOT to combat a frustratingly stubborn peeling problem that does not seem to have a solution in sight.
