Flat Roof Lights BBA Certification Summary

As many of you may have seen we did a recent document in which we showed that to obtain a flat roof that is equivalent to what its been tested for by the BBA, HERTALAN EPDM was the better and more cost effective solution. This got me thinking on what other products we sell. For this blog post I will be looking into the BBA certificates for roof lights.

We all automatically think Velux for roof lights but maybe not always for flat roof lights. Well they do them, but they don't have a BBA certificate for them. They do claim they have a 10 year guarantee but is that long enough for a flat roof light. There are several other companies out there that have longer BBA certificates on their roof lights. Velux's clever marketing over the years seems to be why they are the best known, but for price and lifespan of the product many of their competitors products will last longer and are cheaper. This first blog post covers flat roof windows and the second will cover pitched roof windows.

To find out more I’ve spent time reading and looking at the key important parts of the BBA certificates for the top suppliers to see what there certificates say and I will show what I have found in a simple to follow format. I will do this because if any of you have ever read a BBA certificate they aren't the shortest document to read and aren't always the easiest to get the information we all need if your not familiar with them. If anyone has any further questions or any other supplier that they want checking out I will happily do this for you.

As mentioned above we will cover pitched roof lights in a later blog, but for now I will concentrate on flat roofing sky lights.

Mardome Roof Lights

The first point is who can fit a flat roof window?

Unlike the BBA for the EPDM flat roofing where you need training from the manufacture any competent Builder / Roofer / Contractor can install any of the following skylights.

White Sales

Brett Martin

Both Whitesales and Brett Martin have glass roof windows but neither have BBA certificates to look at, but as glass lasts longer than polycarbonate its not really needed. The limiting factor being the polycarbonate light and the kerb that they all fit to. So by using glass as the option for the light we can assume for Brett Martin domes your talking 35 years of service life at least and 20 years on the White Sales EM-Glaze.


  • Keylite Flat Roof Domes – No BBA available

  • 10 Year Guarantee on the roof light with 1 year on the accessories


  • Flat roof domes and glass – No BBA available

  • 10 Year Guarantee


  • Flat roof domes and glass – No BBA available

  • 10 Year Guarantee

There are no BBA or guarantees to be found from the following manufactures

  • AstroFade


In my own opinion on flat roof lights its either White Sales or Brett Martin with either the Glass option or the polycarbonate. The Brett Martin Mardome Trade range is the cheaper range but White Sales have the longer BBA certificate on the Polycarbonate. Mardome has been tested for longer on their kerbs so really its your choice. I would always recommend sticking to these two manufacturers until someone else out there has a BBA certificate or guarantee that is as good or better.

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