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Calculate roof truss dimensions, count, lumber requirements, and hardware for your building project. Supports King Post, Fink, Scissor, and more truss types.
Width of building (wall to wall)
W-shaped web, most common, spans up to 40 ft
Enter building dimensions to calculate.
Enter dimensions to calculate chords.
Enter dimensions to calculate materials.
Enter dimensions to calculate hardware.
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Simple, single vertical post, spans up to 16 ft
Two vertical posts, spans 16-24 ft
W-shaped web, most common, spans up to 40 ft
Vertical webs, heavy loads, spans 25-40 ft
Vaulted ceiling, spans 20-35 ft
Open center for attic space, spans 24-32 ft
The Fink (W) truss is the most common for residential buildings. Its W-shaped web design efficiently distributes loads and can span up to 40 feet. It's economical to manufacture and provides good attic ventilation space.
Standard spacing is 24" on center (O.C.) for most residential applications. Use 16" O.C. for heavy loads (tile roofs, snow areas) or longer spans. 32" O.C. is only suitable for light loads and short spans. Always consult local building codes and an engineer for specific requirements.
Prefabricated trusses from a truss manufacturer are recommended for most projects. They're engineered for your specific loads, come with stamped drawings, install faster than site-built, and are usually more economical. Site-built rafters may be preferred for complex designs or when cranes can't access the site.
Most residential trusses use 2×4 lumber for spans up to 32 feet. Longer spans, heavier loads, or wider spacing may require 2×6 chords. The engineer specifies lumber sizes based on span, pitch, spacing, load requirements, and local building codes.
Basic residential trusses typically cost $75-200 each for 20-30 foot spans. Larger or more complex trusses (scissor, attic) cost more. Delivery and crane installation add $500-2000 depending on job size. Always get quotes from local truss manufacturers for accurate pricing.
Gusset plates are metal connector plates that join truss members at each joint. They have protruding teeth that are pressed into the wood, creating strong connections without nails or screws. Properly sized and installed gusset plates are critical for truss structural integrity.