House Paint Problems - #1, Blistering

Symptoms: Blistering


Blistering paint is identified by small to medium sized bubbles or blisters under the paint film and is most common on wood siding and trim.

Potential Causes:

•Painting in direct sunlight on a hot substrate (surface being painted) which traps solvent vapor as the paint dries too quickly.

•Painting when the wood is damp causing trapped moisture to expand the paint film.

•Dew, rain or very high humidity after latex paint has dried if the latex paint is of lower quality or the substrate surface preparation was inadequate.

•House moisture escaping through the walls due to improper house ventilation.

Possible Repairs:

•Scrape away blistered paint and sand to bare wood.

•Let wood completely dry.

•Sand, prime and paint in non-direct sunlight and non-humid conditions.

•Use high quality latex paint.

•If due to lack of home ventilation, corrective repairs must be made to properly ventilate the home's walls, roof and eaves, bathrooms, etc.

•Check and repair any loose or missing caulking around windows and doors.

•Consider providing siding ventilation.