The paint that is bubbling is pulling all the underlying layers of paint right off the grooved cedar shingles.
Cedar siding paint bubbles.
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.
These are mainly on the west side of the house but all sides now have at least a few.
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.
It is most commonly seen on wood siding and trim.
The rooms behind the siding are bedrooms and a library office without any plumbing.
Bubbling occurs then gasses or liquids try to escape and get blocked by the new paint.
The old paint s is allowing the gasses out but the new paint is too stretchy and impermeable to these gasses.
Cutting out the blisters priming and repainting solves the problems in those areas but then new bubbles pop up nearby.
Do remove all failing.
After four tries sometimes with and without repriming the result is the same.
The majority of the siding is western red cedar and because these homes are 50 years old the siding is from old growth.
Paint versus stain on cedar siding.
Blistering paint is identified by small to medium sized bubbles or blisters under the paint film.
Plus often the new color is darker than the original causing the siding to heat up in the sun reactivating the old layers.
The took off all of the paint layers down to the primer over the cedar siding.
Now that he s done we have noticed a progressively growing number of paint bubbles blisters.
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.
Paint was applied in direct sunlight on a hot surface which trapped solvent vapor as the paint dried too quickly.
Here are the do s and don ts of painting cedar siding.
The house was last painted 15 years ago without any.