Mineral surfaced roll roofing requires a minimum roof pitch of 1 12 or greater.
Minimum roof pitch for clay tiles.
Ratios from that minimum up to 4 12 which are considered low pitch require double underlayment.
The irc recommends a minimum pitch of 2 5 12 for these materials.
Clay tiles are colorfast which means their tints improve rather than fade over time.
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.
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.
Clay and concrete tile requires a minimum roof pitch of 2 1 2 12 or greater.
All tiles have a minimum roof pitch which is always stated in the manufacturers technical information.
Concrete is long lasting with a minimum lifespan of 50 years depending on climate.
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.
Guidelines for roof sections falling below a 35 pitch.
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.
The minimum pitch for each product can be found in the table below and in the product brochure or within the products pages some tiles and slates incorporate design features allowing them to be laid at a low minimum pitch.