Roof Truss Spacing Requirements

Truss span not greater than 36 feet.

Roof truss spacing requirements.

The standard spacing is 2. Trusses spanning 60 feet or more require a registered design professional to design the temporary installation restraint bracing and the permanent individual truss member restraint bracing 2303 4 1 3. Most economical when the difference in slope between the top and bottom chords is at least 3 12 or the bottom chord pitch is no more than half the top chord pitch. Yet somewhere in the deep dark reaches of history lies the theory wood trusses must be spaced no more than 24 on center or maybe 48 or perhaps even eight or ten feet.

Putting the trusses into place. Once you ve calculated the number of trusses you will need you should purchase the lumber. Minimum roof slope of 3 12. There are also three things that will affect roof truss spacing.

Maximum ground snow load of 70 psf. Metal roofs and pole buildings. The live weight load of a roof basically comes down to the pressure. Although the standard spacing of roof trusses may be the same as that of rafters with 24 inch spacing being a common option the design of a truss may allow for the use of a lower grade of lumber than would be required for rafters with comparable spacing and span.

36 long garage with 12 bays. Truss spacing the distance between trusses. 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. Maximum design wind speed of 140 miles per hour 63 m s exposure b or c.

Building width not greater than 60 feet perpendicular to the truss span. If your local building authority has a rafter spacing code you may not space rafters wider than required by code. Rafter spacing rafters must be strong enough to hold the roof sheathing and the shingles. The dead weight load of a roof is all the different structural elements which can affect the amount of pressure that can be.

Maximum roof slope of 12 12. Typical rafter spacing codes will specify a minimum spacing of 16 inches 19 2 inches or 24 inches. Most are spaced between 18 26 inches apart. The reality is there is no magic number.

If the overhang is more than around 2 6 it will require a 2 6 top cord for the tail section to handle that amount.