It is a simple and straight forward problem but not one that should be guessed at.
My best advise is to have someone locally do the engineering for you. Others such as the attachment to the existing structure, columns, beams/headers, lateral forces etc. The sizing of the joist/rafters is only one aspect to a project as you have described. If your project had a rafter length of 8' or less, a safe and strong method is to use 2x8 framed 16' on center. THIS IS NOT AN RECOMMENDATION, but is only meant to give you an idea of what you might expect. As a general rule, roofs that have a high human occupancy rate should be framed with rafters every 16.' Structures such as sheds or barns can be frames with rafters every 24.' Again, make sure to consult local codes. There are other joist/rafter configurations, but this shape is the most efficient. Using lumber timbers with a min. fiber bending of 1200f and a min. modulus of elasticity of 1,200,000e, I'm came up with a minimun of 4x10 joist/rafters 3'-0' o.c. I did some rough calculations base upon some assumed data, which may or may not be correct for your project. the type roofing material and roof decking to be used, the allowable or desired deflection? Being in Pa., my guess hurricanes and earthquakes are not a problem. you are requesting, even with the necessary data for making such calculations, which you have not provided. members in floors, ceilings and roofs for dwellings or ask your Building Control. The reason is that 26-gauge metal roofs are a lot heavier than their 29-gauge counterparts. You’ll note that this is slightly larger than the recommended spacing for 29 gauge metal roofs. Joe, no one on this site can or is likely to give you the info. What is the purlin spacing for 26 gauge metal roofing The purlin spacing for 26-gauge metal roofing is 4.5 feet.
0 kommentar(er)
