Modules for through- and under-drawing flooring

Claim 1

In a square integrally-formed molded plastic module adapted for laying interlocked with adjacent like modules in an array on a substantially flat and horizontal supporting surface, wherein a flat plate-like body has a multiplicity of apertures through the thickness of the body as through-drainage openings, integral equi-length feet projecting from the bottom for support of the plate spaced from the support surface to provide under-drainage spaces, the improvement comprising: on a first side margin of the module a row of equally spaced short free-ended bar-like projections extending perpendicularly from a margin-adjacent a first straight portion of the body; certain of said feet being each located on said straight portion at a respective region of intersection by a said projection; along a second straight portion of the body at a second side margin, a row of equi-spaced like laterally projecting interlock lugs, having spacings equal to multiples of the spacing of said projections, each lug downwardly offset from the plate top to extend under a like adjacent module and having a vertical aperture adapted to receive therein from above a foot on a said first side of a like adjacent module; each lug having a pair of upwardly extending grip posts thereon inboard of said aperture thereof and adapted in shape and spacing to be resiliently displaced by and to receive and grip therebetween a top-entering respective projection of an adjacent module having a foot entering from above, and to be engaged in, the aperture of said lug.