An adhesive composition for adhesively bonding floor coverings to a variety of substrates. The composition includes 0.2 to 10 weight percent of a plurality of irregularly shaped spacer particles of size 0.5 mm to 10 mm; 10 to 50 weight percent of a moisture curable polymer system; and 40 to 90 weight percent of additives for modifying physical properties of the composition. The adhesive has a composition such that, when cured, results in an elastomeric film of uniform thickness that exhibits controlled moisture vapor transmission and sound abatement properties. A floor structure and a method for constructing the floor structure using the adhesive composition are also provided.