How Far Apart Are Bar Joist Roofs

I investigated an existing bar joist roof for a client just the other day.

How far apart are bar joist roofs.

So the space between rafters can be greater without reducing the maximum span. In areas with mild climates patio roofs are generally designed for loads of 30 psf pounds per square foot. Open web steel bar joists can be spaced up to eight feet apart depending on the size of the steel used and the roof load. With some structures floor joists are required to be 12 or 24 inches apart on center.

You probably should allow for 30 40 lb sq ft snow load the local codes will tell you exactly what. For heavy roofs or in. If the roof is not completely square you can decrease the space between joists but never increase the space. Common spacing for trusses on this type of building is often between 2 and 4 feet but trusses built with advanced designs may allow spacing as great as 8 or 12 feet.

Double the hill and valley width since this is the amount that the panel will overlap the one next to it on each side. Went to the table for the corresponding. Asked the client when the building was built. The same concept holds true for roof trusses.

Proper distance a roof joist is always spaced no more than 16 inches apart from another roof joist. Typically pole barn style buildings in my area have bays distance between trusses of 5 feet to 12 depending on pitch insulation and height. Maximum rafter spans for a patio roof. I measured up the joist using my handy micrometer.

To determine how far apart to set rafters measure the width of the metal panel and then the width of the first hill and valley of the panel. To find the actual distance between the inside edges of each adjacent floor joist subtract 1 inches from either 12 or 24 inches. An essential part of planning a patio roof or gazebo project is determining the number size and spacing of rafters beams and posts according to the loads they will carry. The stuff you see when you look up at the roof in a big box store.

If that seems like a lot in st louis in the mid 80 s we once got 24 of snow overnight. Bar joists meaning roof trusses with z welded between two angles top and bottom. If purlins are laying flat on top of the truss 5 or 6 feet is the max on 2x4 s edge up can go to 12 feet or more. Given that 2x8s are actually 1 inches wide it works out to be 14 inches between each joist.