Polyethylene roof sheets are easy to install, no special equipment needed, the sheets can be cut using a ordinary hand saw, grinder, band saw, jig saw or circular saw.
Use good quality roof screws to fix the sheets to the purlins. Purlin spacing is very important because of the flexibility of Polyethylene Roof Sheeting.
Maximum purlin spacing should not exceed 760mm for IBR.
Do not use warped purlins.
Allow a minimum 5 degree slope for water run off.
Store sheets on a flat surface before installation.
Do not squash the sheet when driving the tek screw through the edge lap, this will distort the edge of the sheet.
Do not butt the sheeting right up against a wall or frame because the material will expand pushing itself up against the obsacle. (This is important when installing in cooler weather.)
We recommend that a spacer be placed between the bottom of the lap and the purlin whilst fastening the roof screw.
Pre drilling the sheeting with larger diameter holes than the screws you use is essential to prevent any damage due to expansion. Thas why its called an expansion hole ! When using a 6mm screw you should drill a 10mm hole
Fix end lap at all corrugations, take your time with the first sheet ensuring it is placed square to the purlin and the structure in general.
For IBR we use spacers 34mm long, cut from 16mm PVC conduit pipe to prevent the sheeting from deforming when the screws are pulled down. The spacers also allow the washers to seal properly against the sheeting preventing any possible water leaks but do not tighten the screws too much to allow the sheeting to expand and contract. If the laminated washer dents you have tightened it too much and should loosen it a turn or two.
Pay attention to all of the above and the installation will be neat and long lasting.