INSTALLATION
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| 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. |
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| 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. |
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| 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 RibRaft Compliant





