Non-air-entrained concrete with a moisture content near saturation is susceptible to surface scaling caused by freeze-thaw cycles. Because of this, designers often require interior concrete slabs to be air-entrained if the slabs will be exposed to a cold, wet environment during construction. Designers take these precautions to minimize the owner's risk of a damaged slab surface and the subsequent cost of repairs. However, a field trial and our studies of petrographic reports related to delaminations indicate that entrained air increases the likelihood that machine-troweled floors will delaminate.
Because delaminations are considered to be a construction defect, the contractor is expected to pay for repairs even though the designer specified the use of the air-entrained concrete that increased the delamination risk. By expecting finishers to hard trowel an air-entrained floor without delaminations occurring, designers transfer risk from the owner to the contractor.