Roof Rafter And Ceiling Joist Framing Section

In a rafter roof all of these components are required to provide.

Roof rafter and ceiling joist framing section.

Section r802 wood roof framing. There are several variables to consider when determining the proper rafter size. Weather you re building a shed roof or adding a dormer to your second story it is important to choose the proper size rafter. They are nominally 2 inches thick actual width usually 1 1 2 inches and come in a variety of widths from 8 to 12 inches.

The following is excerpted from the international code council icc s international building code section on ceiling joist and rafter connections. Roof ceiling framing rafter joists exterior wall nailed to rafter ceiling joists parallel to rafters 2006 irc r802 3 1 in the 2006 edition of the irc the subject of rafter joist connection has been simplified. Not shown are the hip and valley rafters needed to tie the roof together where the rafters are framed at an angle to each other. R802 3 1 ceiling joist and rafter connections.

Joists are traditionally made from timber. The diagram above depicts the cross section of a typical prescriptive roof consisting of the rafters a ridge board ceiling joists and collar ties. R802 1 5 8 exposure to weather. When incorporated into a floor framing system joists serve to provide stiffness to the subfloor sheathing allowing it to function as a horizontal diaphragm.

27 c and for roof framing. This sizing guide for roof rafters will help determine what you need for your small project. A joist is a horizontal structural member used in framing to span an open space often between beams that subsequently transfer loads to vertical members. California residential code matrix adoption table chapter 8 roof ceiling construction.

The general requirement is for all joist to be connected to rafters at the top of the wall. Additionally be sure to adhere to the specific fastening requirements in the 2018 irc table r802 5 2 for the rafter to rafter tie ceiling joist connections. Joists are the parallel horizontal beams that run across an open space joining opposite walls in a building to support both the ceiling below and the floor above. The roof framing modification factors shall take into consideration the climatological location.

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. 2308 10 4 1 ceiling joist and rafter connections. For example in a roof structure where the ridge height is 9 feet above the top of the support walls the maximum height that a rafter tie can be raised is 3 feet 3 9 1 3. The framing details required in section r802 apply to roofs having a minimum slope of three units vertical in 12 units horizontal.