Traditionally, a minimum roof pitch of 20° was recoemmended in BS 5534, but modern tiles and slates have now been designed for applications as low as 15°. It is uncommon to find a roof below 15° but for those very low pitch applications, there are interlocking clay pantiles available, suiteable for use down to 12.5°.
What does minimum roof pitch mean?
Minimum roof pitch is the lowest angle at which a roof can be designed to the roof covering remains watertight. All tiles and slates have a minimum roof pitch which are established to protect the roof from penetration.
Why are low roof pitches more common?
As architects and specifiers continue to push design boundaries, we're often asked about the minimum pitch for a roof tile or slate. We have seen an increase in requirements for low pitch solutions, which is being driven by ongoing demand for large commercial roofscapes alongside a surge in ground floor extensions due to relaxation of planning laws. For example, ground floor extensions often have a limited angle to the roof due to obstructions such as second floor windows, so low pitch tiles are required.
To ensure design possibilities are not compromised as a result of the need to meet low pitches, manufacturers have focused on developing low pitch options aress their product ranges, so that a variety of colours, textures and styles of slates are available.
Minimum pitch of clay roof tiles
Our Melodie interlocking clay pantile can be used in roof pitches as low as a 12.5°.*
Minimum pitch of concrete roof tiles
Our Wessex & Mendip concrete roof tiles can be used down to a minimum 15° pitch.*
Minimum pitch of fibre cement slates
& Thrutone fibre cement roof slates can be used down to a 15°
* Restrictions on rafter length may apply
Our Product Selector tool can also help find the most suitable tile or slate required.
All our low pitch options come complete with matching fittings and accessories for ease of
installation and additional protection.
Minimum pitches for Marley Eternit tiles or slates can be found in either the product brochure
or the product pages here on our website, where they’re located within the technical tab.