Bituminous material thinned with solvents like mineral spirits so it can be applied as a liquid at ambient temperatures. As the solvent evaporates, the material cures into a solid waterproof layer. It is heavily used in cold-process adhesives, roof cements, and damp-proofing mastics.
Heard on the job
Trowel some cutback mastic around that drain bowl to seal the edge.
Also heard as
- cutback asphalt
Related terms
Dampproofing
A thin coating that slows soil moisture through a foundation wall but cannot resist water under pressure.
Hot mop
Waterproofing built from layers of felt mopped down with hot asphalt, or the act of applying it.
Primer
A thin liquid brushed or wiped onto a joint face or deck so the sealant or membrane bonds reliably.