Roof span is also of important consideration as the larger overall roof area will require more stringent roof bracing.
Roof load width skillion.
Roof load width rlw the other important consideration in determining timber lengths and sizes of your pergola is the size and weight of the roofing material the timber structure intends to hold up.
For a skillion or shed roof it s the distance from one supporting wall to the other.
Rlw is used to calculate the sectional size of some roof members and supporting wall.
Wall length rafter thickness.
A butterfly roof has two skillions which angle down towards the centre.
Dead load psf span calculator for wood joists and rafters available for the iphone.
A roof slope of greater than 7 12 such as slopes between 8 12 to 12 12 is where the air dynamic issues start to arise requiring additional roof bracing to help mitigate the higher overall profile of the roof.
This video looks at roof load width rlw.
Variations on the skillion roof include circular or oval shaped designs and the butterfly roof.
Wall length rafter thickness wall width rafter depth wall thick rafter spacing wall height roof angle.
Roof load width rlw and floor load width flw can be determined from as1684 or from the images below.
Determination of roof load width.
Wall width rafter depth wall thick rafter spacing.
Supporting load bearing walls and lintels in lower storey load bearing walls.
Skillion lean to roof framing calculator with running setout points inch all measurements are actual physical finished sizes.
These diagrams may also be used to determine roof load width for floor joists.
Batten width top batten set in batten overhang.
Span calculator for wood joists and rafters also available for the android os.
This is the sixth video in the series on the timber framing code.