Title:
Concrete Q & A: Vapor Retarders and Depth of Cover
Author(s):
Publication:
Concrete International
Volume:
26
Issue:
12
Appears on pages(s):
103-104
Keywords:
DOI:
Date:
12/1/2004
Abstract:
The design for a 4-in.-thick (100 mm) concrete slab-on-ground calls for No. 5 reinforcing bars on 18 in. (460 mm) centers, both ways. The slab will be placed directly on a 6-mil-thick (0.2 mm) polyethylene vapor retarder. I believe the vapor retarder will deteriorate within 10 years. Does this mean that the slab must be thicker, to allow for 3 in. (76 mm) of cover for reinforcement in concrete cast against and permanently exposed to earth, as required by Section 7.7.2 of ACI 318-02, “Building Code Requirements for Structural Concrete”?