Garage Roof Timber Sizes

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.

Garage roof timber sizes.

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. Roof pitch is the measurement of a roof s vertical rise divided by its horizontal run. Discover the standard garage dimensions and sizes here for 1 2 3 and 4 car garages.

This span table is to the format and methodology given in bs 5268 7 2. 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. Find the column for your dead load and spacing and the row for your timber size to find the permissible clear span in metres. For pitched roofs flat roofs and ceiling joists.

I love having a garage. Click on a span to generate a full calculation you can adjust the exact span. Surveyors span tables for designing roof rafters. All the figures are based on roofing tiles or slates laid on timber laths over sarking felt.

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. It is often compared to slope but is not exactly the same. 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. Pitched roof timber sizes.

These spans were calculated using our flat roof joist calculation. You will need to continually measure the roof span and ensure that the size is ok with the building plan and project. We set out illustrated diagrams setting out all key dimensions including width depth and more.