I opened the roof and added new rafters from the outer wall to the higher up top plate of the house like its supposed.
Minimum slope for epdm roof.
Perlite board is not acceptable due to its relative dusty surface and low peel resistance.
Roof slope should be a minimum of 2 to allow for adequate drainage of the roof taking into account the deflection of the roof.
And if the performance of single ply epdm roofing on commercial installations is any measure weatherbond 110 can certainly last much longer than 12 years if it s properly installed.
Normally 1 80 0 72 is the recommended minimum angle for a slope and this is universal across the vast majority of flat roofing systems regardless of the materials that they incorporate.
A minimum slope of 0 25 inches per foot 2 percent is recommended for all low slope roofing systems for adhered systems the substrate must be one that is approved by the system supplier.
The roofer was not calling back and i had to determine with your input a proper pitch for the new epdm.
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.
Pvc membrane assemblies generally have higher maximum roof slope limitations.
Roof ceiling joists nailed to the house.
Some tpo membrane assemblies also have relatively low maximum roof slope limitations.
The idea is to provide positive drainage toward roof drains so there is no ponding water 48 hours after a rain storm.
The minimum roof slope allowed by code for any type of roof is in 12 applicable only to coal tar pitch roof systems.
Higher density products provide improved impact resistance.
The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles.
For example some epdm membrane assemblies have maximum roof slope limitations as low as 1 2 12.
Asphalt shingles continue to be the most widely installed roof covering option in north america.
The following table provides the minimum required allowable roof slope for each type of roofing material mentioned in the code.
The rear room addition flat roof was blue tarped.