Roof Rafter Sizes Uk

2 4 x 1 1034 refer to image to the right 2 65.

Roof rafter sizes uk.

Half building width minus 1 2 ridge thickness. 2 175m is your rafter length. There could be many rafters supporting a roof. Maximum clear span of rafters in metres for roof pitches of between 15 and 45 degrees roof pitch between 15 and 22 5 degrees with rafter spacing strength class c16 size of rafters in mm.

To establish the rafter length we calculate the following. As a general rule roofs that have a high human occupancy rate should be framed with rafters every 16 structures such as sheds or barns can be frames with rafters every 24 again make sure to consult local codes. Clear span on plan. 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.

Span tables for purlin supporting rafters to bs 5268 7 6 imposed loads of 0 75 kn m snow load are applicable to most areas where the altitude does not exceed 100 metres refer to bs 6399 3 imposed loads of 1 kn m snow load are applicable to most areas where the altitude exceeds 100 metres but does not exceed 200 metres but excluding. See rafter run to outer wall calculator below. This demo version is fixed at 1m clear span. Rafter is a sloping beam usually wood that supports a pitched roof.

The full version allows any size. Rafter slope min 15 max 45 degrees. Here the number is 1166 66 inches. It is one of a series of sloped structural members that extend from the ridge or hip to the wall plate designed to support the.

4 8 2 2 4 for one half of your roof s width b skip this step if you already know what measurement half the width of your roof is. Surveyors span tables for designing roof rafters. For pitched roofs flat roofs and ceiling joists. This is the distance between rafter centres.

Usually 400 450 or 600mm but any value can be used up to 610mm max. Rafter run outer wall this should be measured starting from the center of the roof span and then extending to the very edge of the exterior wall. Allow for ridge thickness when determining rafter run to outer wall. If your project had a rafter length of 8 or less a safe and strong method is to use 2x8 framed 16 on center.

This calculator helps you make the rafters of the suitable sizes required for your roofing.