Roof Boards Spacing

Visit the roof framing page for more information on cutting roof rafters and visit the roof pitch calculator for determining rafter lengths based on rise and run.

Roof boards spacing. That can mean costly time consuming callbacks. Apa recommends a 1 8 inch space between panel edge and end joints. Roof truss spacing will vary on the structure s construction. Adjust spacing between deck boards measure to the house at both ends and in the center when you get within about 5 ft.

When to use 12 inch spacing. You want to use 12 inch spacing on smaller pergolas where the weight of many rafters close together won t cause the beam to sag or on pergolas 14 feet in width and under. How many nails per board in roof sheathing. For example in the rafter span table below the highlighted cell in the 40 live load table indicates that 2 x 8 southern yellow pine joists that have a grade of 2 that are spaced 24 apart can have a maximum span of 10 feet 3 inches 10 3 if designing for a live load of 40 lbs ft 2.

This is a centerline measurement from the center of the board so about three quarters of an inch from the side of the board on its narrowest face. Julia i don t know if code applies but in my opinion your deck problems are the result of an inexperienced carpenter. Deck boards should be spaced well apart 1 8 is the minimum and i would go wider usually 3 8. Without that gap you get stuff accumulating between the boards that you can t easily clean out.

There are typically 12 16 or. Plywood and oriented strand board osb like all wood products will expand or shrink slightly with changes in moisture content. The type of nails you ll need to use during the sheathing process depends on the roof material thickness. So the space between rafters can be greater without reducing the maximum span.

The same concept holds true for roof trusses. The last board won t look good if it s skinny or cut at an angle. Roof sheathing basics the skeleton of a roof is formed with rafters or trusses generally spaced 16 inches or 24 inches apart from the center of one rafter to the center of the next. If the wood structural panels are tightly butted there is no room for expansion and buckling can occur.