Roofing Assembly Layers

The system consists of aroof covering and roof deck or asingle component serving as both the roof covering and the roof deck.

Roofing assembly layers.

And nails for base layer spaced 6 152 mm o c. The sy stem consists of a roof cover ing and roof deck or a single component serving as both the roof cov ering and the roof deck. Roofing layers from the framing to the shingles so we ll start at the bottom of the deck and work our way up through all the roofing layers until we reach the shingles and sunshine above your roof. You can usually see the underside of plywood decking from the attic.

Face layer attached with 2 3 8 60 mm 6d cement coated nails 8 203 mm o c. It provides structure by tying the trusses and joists together. Built up roofing also called bur is the most common roofing material used on low slope roofs. The roof deck is the roof layer also called sheathing that is installed between the trusses joists and underlayment layer in a typical roof install.

Bur is preferred for low slope or flat roofs because it creates a continuous sealed surface. It is composed of alternating layers of reinforcing fabric and bitumen asphalt and is finished with a top layer of aggregate such as stone or gravel. Decking most often made out of plywood this roof layer is installed over the framing in a typical roof install. Sound tested with studs 16 406 mm o c.

We ll lay out these important pieces of the roofing puzzle and break down each one so you can fully understand the importance of each layer. The felts are reinforced with either glass fiber mats or organic mats ply sheets and when joined with the bitumen form a durable roofing membrane. The covering applied to the. A roof assembly includes the roof deck vapor retarder substrate or thermal barrier insulation vapor retarder and roof covering.

Base layer attached with 1 7 8 48 mm 6d cement coated nails 6 152 mm o c. All materials used in a roof assembly must be both weather and fire safe as well as compatible with each other. Roofing requirements for the design materials construction and quality of roof assemblies for residences are listed in the california residential code chapter 9. The roof decking acts as a unifying structure by tying the trusses joists together.

A system designed to provide weather protection and resistance to design loads. Here are the layers of a roof in order of application bottom to top. A roof assembly includestheroofdeck vaporretarder substrateorthermalbar rier insulation vapor retarder and roof covering. Built up roofing bur systems popular in north america for more than 100 years built up roofing bur systems are composed of alternating layers of bitumen asphalt and fabrics called roofing felts.