The project is a slab on grade building located in central California. Flooring for said project is a mixture of sheet goods and carpet tiles adhered with glue. The architect has spec’d 4” of crushed rock, Stego 15mil. vapor barrier (Seams,penetrations taped and perimeter sealed to footing with adhesive) topped with 2” sand and finished with a 4”slab.
Additionally, the spec calls for Specialty Products Group Vapor lock 20/20 to be added to the concrete mix design.
QUESTIONS:
Doesn’t it seem redundant to use both these methods for water mitigation?
Does anyone have experience (Good or bad) with the vapor lock product?
Replies
Short answer: Yes.
But, why don't you bring this apparent redundancy up with the architect? The 2" layer of sand tells me they know what they are doing and may have a very good reason for this specification. Additionally, they are the designer of record and when you change his or her spec's during construction, then you assume the liability for any possible failures. As a builder or owner, why would you want to do that?