Garage Roof Timber Sizes

The first step in creating your roof trusses is to cut down the timber panels to the size that you want for your garage roof.

Garage roof timber sizes.

This span table is to the format and methodology given in bs 5268 7 2. The following tables give details of the allowable spans and spacing for some of the more common timber sizes used in traditional roofing construction. In the united states a run of 12 inches 1 foot is used and pitch is measured as the rise of the roof over 12 inches. These spans were calculated using our flat roof joist calculation.

1 2 timber strength class and joist size automatically calculate sizes suitable for supporting the loads below c16 cost effective for most applications c24 stronger more demanding c14 c18 c22 c27 c30 c35 c40. All the figures are based on roofing tiles or slates laid on timber laths over sarking felt. For pitched roofs flat roofs and ceiling joists. Click on a span to generate a full calculation you can adjust the exact span.

Roof pitch is the measurement of a roof s vertical rise divided by its horizontal run. We set out illustrated diagrams setting out all key dimensions including width depth and more. It is often compared to slope but is not exactly the same. Visit the roof framing page for more information on cutting roof rafters and visit the roof pitch calculator for determining rafter lengths based on rise and run.

Surveyors span tables for designing roof rafters. You will need to continually measure the roof span and ensure that the size is ok with the building plan and project. The previous 3 homes i lived in i did not have a garage. Surveyors and structural engineers utilise data from tables below to help calculate the correct size strength and centres of roof timbers for the required spans and loadings.

Pitched roof timber sizes. Rafter span tables use these tables to determine lengths sizes and spacing of rafters based on a variety of factors such as species load grade spacing and pitch. Maximum clear span of flat roof joists in metres for sc3 timber spacing between joists size of roof joist 400mm 450mm 600mm 47 x 97 1 84 1 81 1 74 47 x 120 2 43 2 39 2 27 47 x 145 3 08 3 02 2 87 47 x 170 3 75 3 67 3 42 47 x 195 4 41 4 31 3 92 47 x 220 5 04 4 85 4 41 75 x 170 4 50 4 38 3 99.