Bubbles On Wood Siding

Bubbles caused from a loss of adhesion and lifting of the paint film from the underlying surface.

Bubbles on wood siding.

This problem is far more common when paint is applied to a hot surface. Moisture blistering can be caused by the migration of water through an interior wall to the exterior thus pushing the paint off of the surface. Excess moisture on your painted walls whether from water droplets high humidity leaks or plumbing problems can cause water filled bubbles in the paint originating anywhere from the substrate. To see them you have to be on an angle.

Use a scraper to carefully open the paint bubble. If you re getting bubbles on your new deck it s probably because your new wood hasn t. The best remedy is to scrape and repaint the siding during a warm dry period so the moisture can come out of the wood and prevent future bubbles from appearing. This has prompted some painters to theorize that the linseed oil had dried out in the original layers that sit on the wood and when the fresh top coat dries it pulls the old layer away from the substrate.

Essentially the top layer of paint dries forming a barrier that prevents the solvents from escaping easily. Prevent new blisters by applying two coats of varnish or hand rubbed wood oil on the veneer and keeping anything hot or wet off the surface. Then remove the clamp and wax paper and lightly sand and refinish the surface. A moisture problem would result in unfinished wood behind the bubble.

If your siding has been treated with linseed oil in the past prime and paint with oil based products. The bubbles were really subtle. Let the glue cure overnight. You don t say specifically whether just scraping off the bubbles reveals bare wood or whether the old paint stays intact until the painter sands it off.

What causes bubbles one of the primary causes of bubbles in any kind of finish is moisture in the wood. The new paint has sealed the moisture in the wood and has bubbled up in the places where the moisture is trying to escape. I can see how with the direction of the sun the color of the siding and the reflection from the low e glass the siding could bubble up a bit. Heat problems will result in a visible layer of paint behind the bubble.

Inspect the inside of the bubble. Cover the repair with wax paper and a flat wood block then clamp the blister flat. In a large percentage of cases when we pop the bubbles we notice the bubbles open up right to the bare wood. Bubbles form as the result of a chemical reaction.