Minimum Roof Slope For Tpo

In 12 0 25 in 12 1 19 built up roof coal tar pitch.

Minimum roof slope for tpo.

18 43 asphalt shingles with special underlayment requirements 2 in 12. The minimum slope for a flat roof is 1 4 per foot or 1 4 12 but some owners or insurance companies require a minimum slope of 1 2 per foot. Lapped nonsoldered seam metal roofs with applied lap sealant must have a minimum roof slope of 1 2 12 4 slope. Minimum required slope x in 12 minimum required slope degrees asphalt shingles.

9 46 built up roof asphalt. Asphalt shingles continue to be the most widely installed roof covering option in north america. Some tpo membrane assemblies also have relatively low maximum roof slope limitations. Most metal roofs will have minimum pitches of three in twelve but this might sometimes go down depending on whether there are special installation procedures issued by the manufacturer regarding that particular roofing material.

Tpo performance that s proven to stand the test of time a recent study of everguard tpo roofs installed between 8 and 16 years ago found they all performed above astm standards. The idea is to provide positive drainage toward roof drains so there is no ponding water 48 hours after a rain storm. This is the basis for calculating the angle which is approximately a 1 19 degree slope. The roof system should be designed to prevent ponding of water on the roof surface.

This means for every 12 horizontal units the roof must rise a minimum of 3 vertical units. The important number to remember is 3 12. Ponding is defined as water that has not drained or dissipated within 48 hours after rainfall. Roofing material or system.

For example some epdm membrane assemblies have maximum roof slope limitations as low as 1 2 12. This is the minimum pitch or slope a roofing deck can be in order to install composition roofing shingles on it. Tpo s long term heat uv and natural fungal resistance plus flexibility without need for plasticizers also make tpo a reliable low slope roofing system. 1 16 12 in 12.

To get the minimum pitch for a metal roof the vertical rise per foot is divided by the horizontal slope. According to the international building code the typical built up flat roof that uses tar or asphalt goes by the guideline that for every foot 12 inches of a flat roof a minimum of inch must step up or down. Minimum required roof slope for roofing materials. The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles.

Pvc membrane assemblies generally have higher maximum roof slope limitations.