« Back to Dictionary Index

1. The decomposition of a paint film into a loose powder on the surface; mild chalking, accompanied by satisfactory color retention in tinted paint, is considered a desirable characteristic; heavy chalking which washes off to leave an unprotected surface is highly undesirable; before recoating a heavily chalked surface, all of the chalk should be removed by vigorous brushing. 2. The dusty powdering on an asphalt roof surface that is subject to ultraviolet degradation.

No comments yet.

Leave a Reply