Minimum Flat Roof Thickness

We sell a total of five roofings systems.

Minimum flat roof thickness.

Never attach roof sheathing with staples. 1 2mm standard 1 5mm commercial resitrix. There are two types of flat roof. 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.

Manufacturers express the thickness of metal panels as their gauge with 22 gauge being the thickest and 29 gauge the thinnest of traditionally sold metal roof and wall panels. The problem with metal roofing gauge is that there is a wide range of tolerances. Ultimately a flat roof should play a part in a total architectural composition and has the ability to enhance the aesthetic and practical outcomes of a home. The international codes i codes are the widely accepted comprehensive set of model codes used in the us and abroad to help ensure the engineering of safe sustainable affordable and resilient structures.

The international code council icc is a non profit organization dedicated to developing model codes and standards used in the design build and compliance process. Flat roofs come in many shapes and sizes which include parapet roofs roof decks and green roofs to name just a few of the options available. Minimum thickness most roofs will be sheathed in plywood at least 3 8 inch thick. Four are epdm membranes and the fifth is a polyurathane liquid.

Loads will vary with the. You can read our article about calculating slope for information on the various roof slope notations. As opposed to old built up felt roofing with joins new single ply waterproof membranes are now most commonly used. As the single ply roofing association spra points out this type of flat roofing is strong durable completely sealed and usually lasts at least 25 30 years.

The typical thickness range for sheathing is 3 8 to 3 4 inch. That will suffice on a roof with rafters set 16 inches apart with minimal roof loads. Each gauge represents a nominal decimal range. Cold roofs and warm roofs.

The thicknesses are listed below. Roof sheathing comes in grid marked 4 by 8 foot sheets and should be installed perpendicular to the frame.