When cutting the flat type sheeting it is recommend that you use a good pair of tin snips (you will find cheap tin snips will not work effectively). You can also use a jigsaw with a metal blade.
When cutting profiled type sheeting it is recommended that you use a fibre-cutting disc for metal. This disc can be used with a small angle grinder or larger specialised cutting tools. It is worth noting that the edge of the sheeting, where the cuts have been made using a grinding wheel, heat up rapidly and may burn back the plastic coating and will leave sharp edges that rust. Therefore this is only used when the ridge can hide the edge.
It is advised that for best finishes a nibbler tool is used. This can be hired from a good tool hire firm. Practise on a spare piece of metal sheeting first.
You can also use diamond & tungsten-tipped blades which given a neater finish than the fibre-cutter, although still not perfect.
Fixing sinusoidal corrugated sheets
When fixing the corrugated sheets a fixing should be made at the end of each sheet, including the laps. A fixing should also be made at the top of every other corrugation. When fixing the middle of the sheets to a bearer, a fixing should be made at least every three corrugations. Seam stitches (Tek screws) should be used for added safety and to protect from wind lift.
Trapezoidal (Box Profile)
Box Profiles are named by profile depth and cover width, for example the pictured profile is Accord 32/1000 roof profile.
Fixings points to bearers are made at the bottom (more commonly known as the pan) of the profile using Tek screws withs washers. This allows a secure water tight fixing as the washer will seal once the screw is tightened. Also fixing in the pan eliminates the chance of over tightening and crushing the profile which is a possibilty if you fixed through the top (or crown) of the profile.
Fixing to Metal Purlins
TEK screws have their own drill point, and this will drill though the sheets and the purlins. Since metal purlins and angle iron vary in hardness, it may sometimes be necessary to drill a pilot hole before putting the screw in, to avoid breaking the screw. Remove all swarf from the hole, as it will rust.
We always recommend using sealant such as Butyl when laying our sheets. This is especially important on lower pitched roofs (under 10°).
Seal every lap, before fixing, with the butyl sealant. This will prevent moisture leakage. In places where there is a lot of air moisture (such as by the sea), use a cut-edge lacquer to prevent rusting of the cut edge.
Colour coded caps are available to cover the head of the screw and match your sheets. We quote these as standard with all our fastener packs.