Roof Joist Framing Construction Details

The image below shows a cross section of our simple 12 x 13 house from the joist span tables section of this tutorial.

Roof joist framing construction details.

Joists are placed on edge spaced at 400 600mm centres supported by external and internal load bearing walls. End bearing with rim board. End bearing in hanger on a top plate. End bearing with rim joist.

End bearing in hanger supported by i joist s 44kb. I joists in floor and roof applications. Here we have a wood framed gable roof. Prescriptive roof consisting of the rafters a ridge board ceiling joists and collar ties.

Let s consider a basic gable wood roof framing design. I joist construction details. In addition to floor and roof framing details this guide includes recommendations for cantilevers and placement of web holes. The construction of the flat roof is similar to that of the timber upper floor.

Meeting current irc roof framing requirements means builders are really constructing very simple triangles using the rafters and ceiling joists because triangles are known to be the most stable shape. End bearing in hanger supported by a beam. 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. End bearing with blocking panels.

The function of each component is. Intermediate bearing with blocking panels. Continuing on from part 3. In order to maintain the triangle shape there are specific requirements for how to fasten the corners of the triangle together.

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