Flat Roof Steel Truss Span Tables

The tables below give maximum spans for rafters and beams.

Flat roof steel truss span tables.

The above spans are based on american softwood lumber standard sizes. In areas with mild climates patio roofs are generally designed for loads of 30 psf pounds per square foot. The same thing is true for the bridge of the truss. Roof truss span tables alpine engineered products 15 top chord 2x4 2x6 2x6 2x4 2x6 2x6 2x4 2x6 2x6 2x4 2x6 2x6.

Metal plate connected wood trusses hib 91 by permission of truss plate institute inc. Roof rafter span use this table to determine the maximum lengths of roof rafters based on species and grade of lumber spacing dimensions load and slope. Attached flat roof 1ao page14. Included are a series of representative roof truss span tables that will give you an idea of the truss spans available for a particular load condition load duration lumber type and truss configuration.

The figures are based on quality materials. Use these two tables for roof rafters with a slope greater than 3 in 12. 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. Keep in mind that these tables are for estimations only.

Flat the most economical flat truss for a roof is provided when the depth of the truss in inches is approximately equal to 7 of the span in inches. The load span tables shown below demonstrate only a tiny subset of the possible combinations available with trussteel cfs roof trusses. Finally the truss calculator will compute the best dimensional method to connect the pieces of the truss with steel joints and a bridge. Rafter span tables use these two tables for roof rafters with a slope of 3 in 12 or less.

The more complex the truss framework is the greater quantity of these joints will be required. These steel joints are needed to support the overall truss. Typical roof truss design spans. Roof floor truss manual 7 31 08 10 43 am page 11.

R cb150 16 beam span table used w 3600 width of frame rafter span χ 6410 fascia beam span the cb150 16 beam achieves the 6000mm span for the fascia beam and can be used for the rafters. Roof truss spans every trussteel roof truss is a custom design based upon the unique load span bearing use and code criteria of a particular project. Floor joist span use this table to determine the maximum lengths of floor joists based on species of lumber joist spacing and joist size. For heavy roofs or in areas with substantial snowfall or winds call your local building department for code requirements.