Exterior Wood Finishing

“What is the best exterior wood finishing product ?” is often a question we are asked. Our response is often circuitous.

Paint finishes have come along way in the past 20years. It has left people uncertain as their ‘tried and true’ products are no long available. ‘C2 Guard’, ‘Sico Proluxe’, ‘Penofin’ are all products we have had great success with. The UV inhibiting characteristics are superior which is always something to look for. But what if we were to tell you the way the product is applied is far more important than the product itself?

Every seasoned painter will attest that preparation is key for the effected penetration and adhesion. A clean surface clear of debris is understood as a basic consideration. It goes far deeper than this. Most people when they finish exterior wood do one step at a time. Seems rational-yes? They will completely sand the wood all over the house prior to the start of the application of finish. Here is the issue. The longer the time-frame between when the paint or stain coating is applied will be the key factor in the longevity of the finish. The longer bare wood is exposed-the more exposure UV degradation. This is why factory applied finishes are superior. They are applied before the wood is exposed to UV.

UV destroys the outer most layer(s) of an exposed wood substrate. Destroyed cells cells have a hard time adhering the the cell that is in good condition. This essentially creates a layer of impurity between the finish and the stable substrate. But what is the solution?

-Always select a product with superior UV inhibitors

-Always pre-finish new wood in an area protected from the sun whenever possible. Wood should be dry and cool to the touch.

-Where refinishing, break the job into small bite sized chunks, limiting the amount of time between sanding and re-applying the coating.

-Consult the Master Painter’s Institute (MPI) or a MPI certified partner for advanced advice.

Update November 13, 2021.

In using the C2 Guard, there were some pleasant and unexpected results that could be used aesthetically in the future. To achieve the coloration I was desiring, C2 has admixture pigments that are to be mixed into the base. Have you ever seen the paint store worker measure pigment into a base? It is very methodical and carefully executed. Therefore mixing the pigments at home can never replicate the process. So when pre-finishing our painting project, our stain was ‘batched’ and every shingle received a slightly different colour.

Brick masons come across this all the time. Each palate of bricks slightly vary in colour to the next. This is why when you watch them lay bricks, they pick three-four from one palate before selecting three-four from the next palate and so on.

Using the same methodology, picking boards from different paint runs achieved a pleasing irregularity. The result was a pleasant irregularity. As the rest of the project had a uniform look, we applied another coat to make the surface more uniform. Judge for yourself if this was the best idea?

ps. We do not receive any remuneration for recommending good products, never ever.