Pitched Roof Timber Span Tables

Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads.

Pitched roof timber span tables.

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. Eurocode 5 span tables for solid timber members in floors ceilings and roofs for dwellings 3rd edition. Rise and run means that a 6 12 pitch roof has 6 of rise vertical for each foot of run horizontal. Surveyors span tables for designing roof rafters.

Here we have a wood framed gable roof. Tables 1 and 2 in this chapter are derived from the trada technology ltd. Floor beam span tables of residential structural design we will now look at roof rafter and beam design. The section sizes are based on regularised als or cls timber.

Let s consider a basic gable wood roof framing design. Span calculator for wood joists and rafters also available for the android os. For pitched roofs flat roofs and ceiling joists. Our roof rafter calculator tools are handy for calculating the number of rafters needed rafter length calculator lineal feet of rafter board feed in ridge and sub facia and the total board feet in the roof.

You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths. The image below shows a cross section of our simple 12 x 13 house from the joist span tables section of this tutorial. Also available for the android os. All the figures are based on roofing tiles or slates laid on timber laths over sarking felt.

For timber floors between homes. Pitched roof timber sizes. Trada eurocode 5 span tables 3rd edition bs 8103 3 7 2 3 design of pitched roofs the sizing and spacing of members shall ensure structural stability and provide restraint to the structure without undue movement or distortion. Continuing on from part 3.

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. 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.