Ask the Expert Question-and-Answer Archive

by Ron Joseph

August, 2009

Slow Drying and Wrinkling Ployurethane Porch Paint

Q. I just applied ACE "Gloss Polyurethane Porch & Floor Solvent Based Enamel" to my home concrete porch floor which had been previously painted many years ago. The concrete was clean and dry with no flaking peeling. This newly applied paint is wrinkling in many areas of the floor as it slowly dries (now three days after application and still very tacky). Will the wrinkling disappear as the paint fully dries? It appears that the paint was too thickly applied with a roller. Perhaps this paint was too old (too long sitting on the store shelf)? Please help. Thank you.

A. I referred your question to Rich Thelen of Global Finishing Systems and here is his response:
Most paint companies use a range of 30-80% RH for application range for polyurethanes. Dehumidification is used in areas where high humidity is present. The only way to dehumidify air is through the use of mechanical refrigeration such as chilled water or direct expansion refrigeration systems. In most parts of the country this is not a problem, but in the eastern seaboard states and the hot humid south and southeast, this is the only way to handle the problem. It is very costly.

Regards,

Ron Joseph