Overall flat roof skylight size
Please enter the overall total width & length of your flat roof skylight, then press Resize.
Please read the instructions and diagram and press "Size is correct" to continue to prices.
Please read the instructions and diagram and press "Size is correct" to continue to prices.
Guide for measuring your skylight
The skylight will stand on an upstand that your roofer will create, usually out of wood, covered by the roof's weatherproof membrane.
Recommended upstand sizes are 150mm height as a minimum, and a width of between 75mm to 85mm. Please see the diagrams.
When entering the dimensions of your skylight, you should provide the external dimensions of your upstand and the fitted water proof membrane.
Recommended upstand detail:
- 3 to 5° degree pitch.
- Upstand width 75 - 85mm.
- Upstand minimum height 150mm.
- To ensure the upstand is square a & b should be equal with a tolerance of +/-4mm.
- The length of the skylight should be measured along the slope.
- The upstand is not supplied.
It is the responsibility of the installer to determine the finishing detail of the inside. If you need any further help, why not take a few photos and email them to us for specific advice.
Please note: We are unable to accept responsibility for incorrect measurements.
If in doubt, we recommend to consult a professional installer/builder.
