Cedar Siding Paint Bubbles

Sanding priming and repainting as bubbles appear or strip off all the paint that s bubbling and start.

Cedar siding paint bubbles.

The old paint s is allowing the gasses out but the new paint is too stretchy and impermeable to these gasses. Test results from the forest products testing lab run by the usda for the forest service show that after 12 weeks of exposure to sunlight cedar siding has lost half of its ability to hold a film forming coating system like primer and paint. Plus often the new color is darker than the original causing the siding to heat up in the sun reactivating the old layers. The rooms behind the siding are bedrooms and a library office without any plumbing.

Now that he s done we have noticed a progressively growing number of paint bubbles blisters. It is most commonly seen on wood siding and trim. The majority of the siding is western red cedar and because these homes are 50 years old the siding is from old growth. The problem is many painting contractors do not approach painting cedar siding the right way.

Cedar siding can be one of the most resilient beautiful materials that you can put on your home. Cutting out the blisters priming and repainting solves the problems in those areas but then new bubbles pop up nearby. Here are the do s and don ts of painting cedar siding. I mostly do restorative exteriors which is the complete removal of paint from the siding sand oil prime and two top coats of latex 100 acyrlic.

If you do it right painting cedar siding can last for a long time. Blistering paint is identified by small to medium sized bubbles or blisters under the paint film. After four tries sometimes with and without repriming the result is the same. Paint was applied in direct sunlight on a hot surface which trapped solvent vapor as the paint dried too quickly.

The took off all of the paint layers down to the primer over the cedar siding. These are mainly on the west side of the house but all sides now have at least a few. Do remove all failing. The paint that is bubbling is pulling all the underlying layers of paint right off the grooved cedar shingles.

Allowing fresh siding to weather for as little as two weeks negatively affects coating adhesion.