![]() Based on building codes, a 2×6 can span anywhere from 2’-1 to 20’-8 depending on the affecting factors. ![]() Additionally, compres-sion perpendicular to grain design values (F c ) are included as a consideration for selection of joists and rafters. The distance a 2×6 can span is determined by the species, grade, location, use, load, and spacing. These span tables for joists and rafters are calcu-lated on the basis of a series of modulus of elasticity (E) and bending design values (F b). Let me also say that you did not provide sufficient pictures to accurately assess you question… the span of the deck may be 12 feet…yet the rafters may be going back another 4 foot up the roof to get the 3/12 (probably 2/12) pitch, unless the framer busted the load down with bracing then your true span in the above scenario would be 16 ft. A general rule of thumb for joist span is 1-1/2 times a board’s depth in feet, however, it’s not that simple. Limited to span in inches divided by 240. Dead Load of 10 psf determines the required bending design value. _ (species of wood), what would be the minimum for a slope of less thanĪt any rate, 2x8 rafters will typically span almost 14 ft. DESIGN CRITERIA: Strength - Live load of 50 psf plus. It is all based on the wood specie, grade, spacing, and loading. I have a porch with a span of _ feet with 2x8 rafters at 24" on center using According to the IRC, a 2圆 floor joist can span anywhere between 6’-10 and 12’-6. Rafter Span Tables - Use these tables to determine lengths, sizes, and spacing of rafters based on several factors such as species, load, grade, and spacing. The information that you did not provide us is the span of the enclosed porch. Rafter spacing is typically 16" for stick frame and 24" for trusses. ![]() Stud spacing is usually 16" and at times 24" on center. ![]() In addition, the standard roof rafter spacing used in the roof framing includes 12, 16, 19.2, or. However, rafter spacing may also be calculated by a professional structural engineer. Most species used in residential construction are Pine, Spruce, Fir.įloor Joist spacing is usually 16", 19.2" and 24" on center. Calculating the rafter spacing is determined by the prescriptive tables provided by the International Residential Code (IRC), which is found in Chapter 8. ![]()
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |