Here we have a wood framed gable roof.
Residential roof framing plan.
The provisions for prescriptive roof construction are found in chapter 8 of the irc and in section 2308 of the ibc.
A design and construction handbook nahbrc 1994.
In buildings including residential structures framing systems typically consist of the roof structure that supports the roof.
Common types of roofs and basic framing terms.
The image below shows a cross section of our simple 12 x 13 house from the joist span tables section of this tutorial.
Depending on how wide the home is you can divide the total length in feet by two to determine how many trusses will be needed.
It is the form most commonly used by.
Intricate roofs have many parts that incorporate several of the basic roof designs such as a gable roof sitting atop a gambrel or variations of the gable valley roof design using one or a variety of different types of roof trusses also see our very detailed diagrams showing the different parts of a roof truss.
Floor beam span tables of residential structural design we will now look at roof rafter and beam design.
Continuing on from part 3.
The first approach to achieving a strong durable struc ture involving economical use of materials is to follow a basic modular plan for layout and attachment of framing members.
The framing of a basic gable roof is based on a right angle triangle and the various roof framing components fit the triangle.
Let s consider a basic gable wood roof framing design.
The run or half the building span is the base of the triangle.
An example of each is shown in figure 2 1.
For high wind conditions prescriptive guidelines for design and construction may be found in the wood.
Types of roofs the most commonly used types of pitched roof construction are the gable the hip the intersecting and the shed or lean to.
More complex roof designs will need to account for this accordingly.
Gable a gable roof has a ridge at the center and slopes in two directions.
Deck exterior and interior load bearing walls beams girders posts and floor framing.
Similar prescriptive design aids and efficient framing practices can be found in cost effective home building.
For most load bearing requirements a roof truss will need to be placed every two feet along the walls.
The size of the ridge board and hip and valley rafters.
Within limitations which include among others building size roof pitch and design loads the allowed span for conventional rafters can be selected from tables rather than designed through engineering calculations.
As you can see the initial plan for framing your roof needs to take into account several key variables such as the shape of the roof and any relevant community building codes.
The rise or height of the roof at its peak is the altitude of the triangle.
Framing must transfer all gravity uplift and lateral loads to the foundation.
Such methods use a 4 foot design module which governs a 16 inch spacing of joists studs rafters and panel sheathing products.
Also different architectural styles will use the same type of roof.