Roofing: How to Strengthen Roof Structure
Choosing a roof structure
A roof must be strong enough to stand up to severe weather without collapsing and secure enough to keep out water. Once a roof fails, it exposes other parts of the structure to damage and can lead to total destruction. The following are critical steps for creating the strongest roof structure possible.
- Determine whether your roof structure will be conventionally framed or will use a pre-engineered truss system.
- Choosing engineered wood products such as wood trusses and I-joists can reduce waste and increase framing efficiency. In many situations, it can even save time during construction when properly coordinated. Conventional framing using wood framing members is another option to form and support the roof.
- Individual components must be cut and fastened together on-site to ensure a sound roof structure. These components generally include the following:
- Rafters and ridge beams
- Ridge straps over the rafter peak to connect rafter pairs for uplift
- Collar ties between rafter pairs
- Diagonal support brace from rafter to a bearing wall
- Ceiling joists
- Additional bearing partitions to support ceiling joists and diagonal support braces
What You Should Know
In many instances, the required bracing, support, and connection detailing for conventional framing is not shown or specified on the construction documents.
Pros and Cons:
This can lead to decisions made in the field which can adversely affect the performance of the roof structure under hurricane conditions.
On the other hand, the engineered roof wood members are fabricated in a quality-controlled environment to design specifications and then shipped to the job site for erection.
Whatever system you use, make sure the roof structure is designed to support the roof covering you plan to use and that each roof framing member is anchored to the wall. Some roof coverings, like tile, are heavy and the additional weight needs to be considered when designing the roof framing.
© 2012 Insurance Institute for Business & Home Safety