Modified Bitumen Roof Minimum Slope

The following table provides the minimum required allowable roof slope for each type of roofing material mentioned in the code.

Modified bitumen roof minimum slope.

Self adhered modified bitumen roof systems come with several advantages over tpo single ply roofing systems. For example the international building code 2018 edition ibc 2018 prescribes a 1 4 12 minimum roof slope for asphalt built up polymer modified bitumen thermoset and thermoplastic single ply and liquid applied membranes in new construction. Tamko modified bitumen roof system over steel decks miami dade county noa. Liberty sbs self adhering base ply sheet is a self adhering roofing membrane designed to be used as either a base sheet or a ply sheet in your modified bitumen roofing system providing long lasting protection for low slope roofs.

The minimum roof slope allowed by code for any type of roof is in 12 applicable only to coal tar pitch roof systems. Tamko modified bitumen roof system over wood decks miami dade county noa 17 0222 09 expiration date. Limited warranty 5 year limited warranty. Bitumen roof advantages and disadvantages.

If you install the smooth product cover it with aluminum coating. Thermoplastic polyolefin tpo single ply roofing membranes are typically offered with 20 year warranties but manufacturers are now on their sixth formula iteration and have yet to effectively resolve cracking erosion and other. Modified bitumen roofing minimum roof slope roof pitch r905 11 1. This 1 4 12 minimum roof slope requirement also applies to spray polyurethane foam spf roof.

Modified bitumen roofing may have a granular surface as shown here or it may be smooth. Renting a large propane torch is inexpensive. This means for every 12 horizontal units the roof must rise a minimum of one fourth vertical unit. Modified bitumen membrane roofs must have a design roof slope of 1 4 12 or greater 2 slope.

Modified bitumen roofing was designed for use on buildings that have a low slope or flat roof. You can read our article about calculating slope for information on the various roof slope notations. Technically we are talking about low slope roofs that have a slope less than or equal to 3 12. These steps show a torch down method which looks a bit scary but actually is not too difficult.

One of the longer lasting roofing options for flat roofs is bitumen roofing or a modified bitumen roof.