All tiles have a minimum roof pitch which is always stated in the manufacturers technical information.
Minimum roof pitch for clay tiles.
This minimum pitch is important if tiles are laid below the recommended minimum pitch there is an increased chance of water getting through which can damage the underlay and battens over a prolonged period.
Metal roof shingles require a minimum roof pitch of 3 12 or greater.
All tiles and slates have a minimum roof pitch which is set out in order to protect the roof from water penetration.
Clay and concrete tile requires a minimum roof pitch of 2 1 2 12 or greater.
For many years 20 was recommended as the minimum pitch for clay tiles but this has decreased in the modern era down to 15.
On some developments design limitations can arise on comparatively small areas of the roof which restrict the available roof pitch to below 35 which is the minimum pitch recommended for all plain tiles in bs en 5534.
Concrete is long lasting with a minimum lifespan of 50 years depending on climate.
Anything lower than this angle is rare and although there are specific products that can go lower 15 is the most common minimum angle for clay tiles.
Guidelines for roof sections falling below a 35 pitch.
Ratios from that minimum up to 4 12 which are considered low pitch require double underlayment.
It is uncommon to find a roof below 15 but for those very low pitch applications there are interlocking clay pantiles available suitable for use down to 12 5.
Clay tiles are colorfast which means their tints improve rather than fade over time.
Traditionally a minimum roof pitch of 20 was recommended in bs 5534 but modern tiles and slates have now been designed for applications as low as 15.