What does Metrotile’s fire rating mean?

residential area from above Metrotile lightweight roofing Brindle

Fire ratings for roofing determine the fire resistance of a roofing material, and how long it can withstand fire. Metrotile’s roofing has been awarded the highest possible fire resistance rating, EXT.S.AA, making the roof material of choice for a variety of builds. Here’s what our fire rating really means for your project:

Ratings

Fire ratings typically involve a series of letters that determine the type and position of the roof. For example, if you see EXT, this will mean the external roof. The following letter determines the type of roof. An S would mean the roof is sloped, an F will mean that the roof is flat. The following letters are broken down into two sections.

Fire resistance

The first letter dictates how fire resistant the roofing is. Roofing rated D means it can be penetrated straight away when it comes to a fire. B and C ratings are normally given to materials that can be penetrated by fire within 30 minutes. If a product has a fire rating of A, then it will withstand fire for up to a maximum of 60 minutes.

Fire spread

As well as ensuring their roofing is resistant against fire, they may also wish to ensure that there is as little fire spread as possible. In this regard, a rating of D means that the product will continue to burn five minutes after the flame is removed, or there’s a spread within five minutes. The C rating means that there was fire spread of more than 21 inches, whereas B informs us that the spread is 21 inches or less. An A rating means that the fire will not spread for 60 minutes.

Metrotile’s rating of EXT.S.AA ensures that our lightweight roof tiles are fire resistant, tested thoroughly to provide the safest roofing solution. If you’re currently looking to ensure that your new project has a strong deterrent against fire, then why not get in touch? You can call us on 01249 658 514 or fill in our contact form and we will get back to you.