STEP 1 The site must be levelled. all plumbing pipes fixed in place andthe formwork positioned. STEP 2 Plastic sheeting of 250 Microns is spread over the site with all laps taped.
STEP 3 Starting from the corner of the site lay Voidforms in grid pattern using WJ100 and WJ101 spacers. The Voidforms can be easily cut to size and to fit plumbing fittings. STEP 4 Place the reinforcement bars between the Voidforms and the top mesh over the total area. Ensure tie laps are used as required.
STEP 5 Place chairs under the mesh at the rate of 4 per Voidform®. STEP 6 In a single concrete pour, partially cover the Voidform before filling the ribs. (This will hlep prevent the Voidform from floating).

Firth Corporate
Firth RibRaft Compliant