I cant find any info about this online yet to me it seems quite important!
I will have polycarbonate sheets for my patio cover. I am first to build the frame, I may go for 700mm beam centres, and so I thought 700mm wide sheets. BUT... the rafter bars have a thickness between sheets, so should I not be adding on that thickness to my beam centres? So if say the thickness is 15mm, should I assume a spacing between sheets of say 20mm, and so my beam centres should be 720mm, else the sheets wont fit. If I put the rafter bars in as I lay the sheets I'll not be over any beams toward the second half of the roof, each bar will edge further over. If I put the bars on 700 centres, I assume the 700mm sheets wont fit.
Or when I order a 700mm sheet do they take into account the rafter bar width so in fact it may be something like 690mm wide?
Sheets are often sold in set widths like 400mm, 600mm etc. Beam centres are always are referred to as 400mm, 600mm etc. so it just seems strange that the off the shelf sheet widths and standard beam centres either dont take into account rafter bar widths or the sheets are actually supplied thinner.
Honestly cant find any info about this, but its critical in the planning of it of course, I would have thought it should be on all the polycarbonate sheet supplier sites.
I'll probably get custom size due to the length (3.6m), so need to know what width for the sheets if its 700 beam centres.
Thanks
I will have polycarbonate sheets for my patio cover. I am first to build the frame, I may go for 700mm beam centres, and so I thought 700mm wide sheets. BUT... the rafter bars have a thickness between sheets, so should I not be adding on that thickness to my beam centres? So if say the thickness is 15mm, should I assume a spacing between sheets of say 20mm, and so my beam centres should be 720mm, else the sheets wont fit. If I put the rafter bars in as I lay the sheets I'll not be over any beams toward the second half of the roof, each bar will edge further over. If I put the bars on 700 centres, I assume the 700mm sheets wont fit.
Or when I order a 700mm sheet do they take into account the rafter bar width so in fact it may be something like 690mm wide?
Sheets are often sold in set widths like 400mm, 600mm etc. Beam centres are always are referred to as 400mm, 600mm etc. so it just seems strange that the off the shelf sheet widths and standard beam centres either dont take into account rafter bar widths or the sheets are actually supplied thinner.
Honestly cant find any info about this, but its critical in the planning of it of course, I would have thought it should be on all the polycarbonate sheet supplier sites.
I'll probably get custom size due to the length (3.6m), so need to know what width for the sheets if its 700 beam centres.
Thanks
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