Modified Bitumen Roof Minimum Slope

Modified bitumen roofing may have a granular surface as shown here or it may be smooth.

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. This 1 4 12 minimum roof slope requirement also applies to spray polyurethane foam spf roof. Advantages there are a wide range of methods available for installing modified bitumen roofing from using a hot torch to using a sealant backed peel and stick rolls. Renting a large propane torch is inexpensive.

Bitumen roof advantages and disadvantages. Technically we are talking about low slope roofs that have a slope less than or equal to 3 12. Self adhered modified bitumen roof systems come with several advantages over tpo single ply roofing systems. You can read our article about calculating slope for information on the various roof slope notations.

This means for every 12 horizontal units the roof must rise a minimum of one fourth vertical unit. 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. Tamko modified bitumen roof system over wood decks miami dade county noa 17 0222 09 expiration date. Modified bitumen is a type of asphalt product that can be applied in a number of ways to the roof in both hot and cold temperatures.

These steps show a torch down method which looks a bit scary but actually is not too difficult. The minimum roof slope allowed by code for any type of roof is in 12 applicable only to coal tar pitch roof systems. Modified bitumen roofing was designed for use on buildings that have a low slope or flat roof. Modified bitumen roofing minimum roof slope roof pitch r905 11 1.

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. One of the longer lasting roofing options for flat roofs is bitumen roofing or a modified bitumen roof. Modified bitumen membrane roofs must have a design roof slope of 1 4 12 or greater 2 slope. Limited warranty 5 year limited warranty.

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.