Flat Roof Roof Joist Span Calculator Uk

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.

Flat roof roof joist span calculator uk.

You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths. Read the notes at the bottom of the table for assumptions references and related standards. There is no standard universal roof pitch roof pitch varies depending on culture climate style and available materials in the usa the range of standard pitches is anywhere between 4 12 and 9 12 in the uk the typical house has a pitch between 40 50 although 45 should be avoided. 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.

What is the standard pitch for a roof. These spans were calculated using our flat roof joist calculation engine. These span tables are the equivalent of other industry standard span tables and are calculated to the same standards. 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.

Flat roof joist calculator. Suitable for uk building regulation approval. 1 enter joist details 1 1 span and joist spacing. This is the distance between joist centres.

Span tables for flat roof joists to bs 5268 7 2 imposed loads of 0 75 kn m for maintenance and snow load are applicable where there is no permanent access no fixed ladder or staircase and most areas where the altitude does not exceed 100 metres refer to bs 6399 3. Usually 400 450 or 600mm but. 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. Contemporary houses often have flat roofs which shouldn.

Surveyors span tables for designing roof rafters. Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads. The full version allows any size.