Maximum Spacing Of Roof Trusses

Spaced sheathing or 1x boards may be reduced slightly.

Maximum spacing of roof trusses.

Roof pitch between 30 and 45 degrees strength class c16 roof pitch between 30 and 45 degrees strength class c24. Span of roof truss 7 2m spacing of the truss 3 0m nodal spacing of the trusses 1 2m. Allowable spans for 2x4 top chord trusses using sheathing other than plywood e g. Common spacing for trusses on this type of building is often between 2 and 4 feet but trusses built with advanced designs may allow spacing as great as 8 or 12 feet.

Pitch this is the incline of the roof expressed as a fraction. So the space between rafters can be greater without reducing the maximum span. Permanent dead loads self weight of long span aluminium roofing sheet 0 55mm gauge thickness 0 019 kn m 2 weight of ceiling adopt 10mm insulation fibre board 0 077 kn m 2 weight of services 0 1 kn m 2. Typical roof truss spacing means that they are usually about 24 inches from centre which means at the centre of one truss there will be a two foot gap or twenty four inch gap until the centre of the next truss.

But the tables that follow are a lot more specific. This diagram illustrates the typical. 2x4f 2000psif 1100psie 1 8x10 2x6f 1750 psi f 950 psi f 1900 psi e 1 8x10. Spacing a live load deflection limited to l 240 maximum and use lumber properties as follows.

Room in roof attic trusses with the ever present need to optimise space in our homes room in roof or attic trusses can provide valuable additional living areas within the roof space. The trusses should be a little longer than the exact width to allow for overhang and you will need sufficient trusses to mount across the length. Most are spaced between 18 26 inches apart. When constructing a roof framework the rule of thumb is that any purlin should have a minimum nominal depth and width of 76 mm or 50 mm and max centre to centre spacing between the purlins ought to be 1 2 m.

Once you ve calculated the number of trusses you will need you should purchase the lumber. Putting the trusses into place. While pitch and slope are used interchangeably they are not the same span also known as gable width this is based on the total footprint of the house and refers to the distance between two exterior. Joints between purlins next to one another should be staggered.

The same concept holds true for roof trusses. A large proportion of all trussed rafters produced are now room in roof or attic trusses which offer up to 65 more living space. Vertical and suitably located where necessary temporary bracing should be used to maintain spacing and to keep trusses vertical evenly spaced at maximum 600mm centres. Maximum clear span of purlins in metres for roof pitches of between 30 and 45 degrees roof pitch between 30 and 45 degrees strength class c16.