What Size Rafters For Patio Roof In Illinois

When building a patio roof in Illinois, choosing the right size rafters is crucial for ensuring the structural integrity and longevity of the structure. The size of the rafters will depend on several factors, including the span of the roof, the spacing between the rafters, the type of roofing material used, and the local building codes.

The span of the roof refers to the distance between the supports for the rafters. In general, the longer the span, the larger the rafters will need to be. The spacing between the rafters is also important, as closer spacing will provide more support for the roof. The type of roofing material used will also affect the size of the rafters. Heavier roofing materials, such as tile or slate, will require larger rafters than lighter materials, such as asphalt shingles.

In addition to these factors, local building codes may also specify the minimum size of rafters that can be used. These codes are in place to ensure that structures are safe and meet certain standards. It's important to check with the local building department to determine the specific requirements for your area.

As a general guide, the following rafter sizes are commonly used for patio roofs in Illinois:

For spans up to 10 feet, 2x6 rafters spaced 16 inches on center are typically sufficient.
For spans up to 12 feet, 2x8 rafters spaced 16 inches on center are recommended.
For spans up to 14 feet, 2x10 rafters spaced 16 inches on center are typically required.

These are just general guidelines, and the actual size of the rafters may vary depending on the specific factors mentioned above. It's always best to consult with a qualified contractor or engineer to determine the appropriate size of rafters for your patio roof.

In addition to the size of the rafters, it's also important to consider the slope of the roof. The slope of the roof will affect the amount of weight that the rafters need to support. A steeper slope will require larger rafters than a flatter slope.

By following these guidelines and consulting with a qualified professional, you can ensure that your patio roof is properly supported and will provide years of enjoyment.