Rafter Sizes For A Pitched Roof Uk

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.

Rafter sizes for a pitched roof uk.

In this example we have a customer with a building width of 4 8m wide and the pitch of the roof is 25. If your project had a rafter length of 8 or less a safe and strong method is to use 2x8 framed 16 on center. Clear span on plan. You can assess this in two ways either as the roof pitch angles which the rafters make with the horizontal or the proportion between the run and the rise of the roof.

Surveyors span tables for designing roof rafters. This is the distance between rafter centres. 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. Roof pitch between 15 and 22 5 degrees with rafter spacing strength.

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. 2 4 x 1 1034 refer to image to the right 2 65. Roof pitch refers to the slope which the rafter creates. 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.

Often you express roof pitch as the ratio between the rise and the run in the form of x 12. For pitched roofs flat roofs and ceiling joists. Roof pitch between 15 and 22 5 degrees with rafter spacing. 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.

Maximum clear span of rafters in metres for roof pitches of between 15 and 45 degrees size of rafters in mm roof pitch between 15 and 22 5 degrees with rafter spacing of roof pitch between 22 5 and. The full version allows any size. To establish the rafter length we calculate the following. Roof pitch between 15 and 22 5 degrees with rafter spacing strength class c16.

Rise and run means that a 6 12 pitch roof has 6 of rise vertical for each foot of run horizontal. Rafter slope min 15 max 45 degrees. 2 175m is your rafter length.