Thanks for that, brilliant. I'm looking to roof a pergola and have taken some pointers from your video. Many thanks. Quick question though... could you have used wider sheets to cut down on the number of sheets such as the 1200mm (or even wider) you mention? 👍
Hi there, no worries :) Yes you can absolutely use wider sheets. I'd normally use 1220mm but I happened to have some 610mm that I needed to use. If you use 1220mm (or wider) you need rafters at around 600-650mm apart. So some of these will be in the middle of the sheet. In which case you use the Twinwall fasteners to fasten the sheet onto the rafter (drilling an expansion hole first). Hope that helps! Kurt.
Hi there, our H snap joiners are designed to be screwed through the bottom, into the rafter. Then you put the sheets on and then snap the top part of the H joiner on. If the sheets are 1200mm wide, they will also need to be screwed through the sheets into the rafter that goes under the middle of the sheet. More info here: twinwall.co.nz/ Thanks, Kurt.
I'm looking to replace a clear corrugated pvc roof. The timbers are already installed but not to vertically every 4ft however there are horizontal latts going across so can the multiwall just be fitted onto the latts?
Hi there. Yes, generally it can be fitted directly on to the horizontal purlins, as long as the joiners that you're using are suitable for that. It should show in the installation instructions for your system whether it's ok to only be supported on the purlins (depending on how far apart they are - usually around 800mm 32in or so). Thanks, Kurt.
A very useful video that will give me the confidence to replace my poly twinwall porch roof. The existing roof is 2m wide and 1m long with only outer supports. Do you think it would be better to add a middle support? Thanks again Colin
Glad it was helpful :) Yes you would need to add supports no further apart than 600mm (for 6mm Twinwall) or 800mm (for 8mm). Otherwise it will flex too much. Regards, Kurt.
Hi there, thanks for the vid, the spacings between the rafters you mention need to be 640mm, is this centre to centre, inside or outside dimension? Cheers
Hi there, no worries. It depends on the width of the sheet, and the inside width of the joiner. E.g. if your sheets are 610mm wide, and you allow a 30mm gap for the joiner, then you'd have 640mm spacings centre to centre. There's a diagram here that may help: sunnyside.co.nz/product/twinwall-polycarbonate-roofing/ Thanks, Kurt.
Hi i got glazing bar screw to timber put 100mm polycarbonate sheet but when i wont put cap on its not cliping this screw on this way. If polycarbonate sheet was 160mm wilby fine. Any ideas? Thanks
Hi - I noticed you were kneeling on the panels. I was not aware they were strong enough to support a man’s weight. It won’t crush the channels in the panels to kneel on them while using the rubber mallet?
Hi there, good spotting. Ideally you wouldn't kneel on it, but because I've used it for some time I know how much weight I can put on it. Too much weight, especially on the point of the knee, and you will crush the channels. Best practice would be to use a drop sheet and plank on top if you need to put weight on it :)
Thanks :) We actually supply the Twinwall, so if you're in New Zealand it can be purchased from sunnyside.co.nz. If you're not in New Zealand, if you search for Twinwall or Multiwall polycarbonate in your area you should find some suppliers. Thanks, Kurt.
Hi there, generally you don't need to cover the ends of the joiners. However if the top end is exposed (e.g. not under a flashing) then you could put some sealant in there. Or if you're in a very dusty environment you could put sealant or tape on both ends of the joiner. Thanks, Kurt.
