velux window



my brother in law is fitting a 550x780 centre pivot window hopefully this week weather permitting on my bungalow above bathroom, i would like to know the exact size for the openening in the roof to make and is the top of the frame fixed flush with top of rafter , just really want it make as simple as possible.we have double roman tiles and are using a edz flashing kit, all hints helpfull thanks john
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yeah i got the instructions freddy but i was looking for the exact measurement,which it isnt showing that well,why i advertised here hoping some one can give me a simple answer to a 550x780 window
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I have just phoned them and there answer was make it 40m bigger all round ,wish they could had made it clearer on instructions lol , any way thank you
2 Feb 2006
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United Kingdom
the velux is fixed to two roofing battens via brackets that are installed on the corners of the window frame. there will be a horizontal, top and bottom batten. you will have a specific set of instructions that will outline the tolerance parameters.

the battens will need to be approximately 40mm further apart than the frame height dimension.

the bottom batten will need to be fixed 80mm up from the top edge of the bottom course of tiles.

the top batten will then be set at the height of the window +40mm.

the side rafter measurement is less critical. just make sure that the entire width of the frame is visible from below. 20mm tolerance up each side will be more than enough.

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