Roof Joist Construction Details

End bearing in hanger on a top plate.

Roof joist construction details.

Secure each tile with two large head roofing nails. Good installation begins with specification of the correct joist for the application. The basic construction of a flat roof starts with roofing timber that is laid across two upright items usually two walls. Two nails are used for widths up to 8 inches.

Refer to the details. Lay 10 or 12 inch tiles with 1 inch head lap on the sides of dormers. I joists in floor and roof applications. They differ considerably from the conventional gabled roofs in shape and construction.

So the only reason these planks are called roofing joists is because they run horizontally or nearly horizontally to the ground. The construction of the flat roof is similar to that of the timber upper floor. Whenever possible begin trim installation at the downwind end of the roof farthest away from the source of prevailing winds to al low flashing laps to face away from wind driven rain. I joist construction details.

End bearing with rim joist. End bearing with blocking panels. Intermediate bearing with blocking panels. Because i joists are straight and true it s easier for builders to avoid crowning and maintain a level framing surface.

End bearing in hanger supported by a beam. Mono pitched roofs are also known by the names of skillion roofs shed roofs pent roof and lean to roof. Joist is a term used in construction for load bearing planks that run horizontally or nearly to horizontally to ground. Double the tiles at eaves and project them 1 inch over the rear edge of gutters.

End bearing with rim board. Trada and approved document part a give guidance on sizes of joists for flat roofs relating to spans and loading. Joists are placed on edge spaced at 400 600mm centres supported by external and internal load bearing walls. While the gabled roof is always pitched in two directions the mono pitch always slants in a single direction.

In addition to floor and roof framing details this guide includes recommendations for cantilevers and placement of web holes. For additional stability you can also use steel joists that are built into one or both of the walls. They are ideal for long spans including continuous spans over intermediate supports. With single course applications nails are driven one inch above the butt line of the succeeding course.

This will give additional stability to the roof structure. End bearing in hanger supported by i joist s 44kb. Lay all tiles within 1 foot of hips ridges and abutting vertical surfaces in roofer s cement. In double coursing the under course is attached to wood sheathing with three nails or staples.