How big should my roof opening be to install a skylight?

To install a fixed or openable plastic skylight, hybrid skylight or flat roof window, you always need a PVC curb. 

The PVC curb is heat-resistant (obviously keep the welding flame away from the curb) and remains intact during installation of the roof covering.

Roof opening PVC curb 16/20 EP:

With the lining groove, you connect the ceiling finish seamlessly: allow 4 cm extra roof opening for this. A 16/20 PVC curb with daylight size B of 100 x 100 cm has a roof opening C of 120 x 120 cm if you make no use of the lining groove. Allow for a roof opening of 124 x 124 cm if you do make use of it.


Roof opening PVC curb 20/00 EP:

Thanks to the lining groove of this skylight curb, you can connect the ceiling finish seamlessly. Allow 4 cm extra roof opening for this. E.g. A 20/00 EP PVC curb and a 20/00 EP-S curb with a 100 x 100 cm (B) daylight size has a 100 x 100 cm (C) roof opening if you don’t use the lining groove. Allow for a structural opening of 104 x 104 cm if you do use it.

The 20/00 curb EP comes with an anodised aluminium profile (flashing profile) as standard. The profile has 4 plastic corner profiles and is fixed with stainless steel self-tapping screws with Nyplas washers. The flashing profile allows you to easily pull up the roofing.

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