Roof Structural Members

Wall beams or plates sometimes described as a type of purlins that run horizontally under the roof truss and connect it to walls.

Roof structural members.

In the uk a concrete tiled roof would normally have rafters at 600 mm 24 in centers roof battens at 300 mm 12 in centers and ceiling joists at 400 mm 16 in centers. One of a series of diagonal members of the truss that meet at the apex in order to support the roof deck and its loads. A waterproofing seal installed along the roof s valley line with taktekkernbergen no. A purlin is a horizontal piece of timber or metal which supports the roof s rafters or decking and helps to prevent your roof from sagging.

Rafters have a tendency to flatten under gravity thrusting outwards on the walls. They provide the support for the external roofing material. A timber roof truss is a structural framework of timbers designed to bridge the space above a room and to provide support for a roof. Trusses usually occur at regular intervals linked by longitudinal timbers such as purlins.

The roof system consists of several very important parts. Purlins horizontal members connecting rafters. The united states still uses imperial units of measurement and framing members are typically spaced sixteen or twenty four inches apart. When these framing members have been omitted and when there is no structural ridge design over which a roof is suspended the inwards force on the upper roof combined with the downwards movement of the ridge will pull the lower half or more of the rafter away from the ridge board.

For larger spans and thinner walls this can topple the walls. Straps and different types of bracing. Rafters sloped parts of the truss running from the wall beams on both sides to a ridge board which is a horizontal member on top of the roof. A slab is usually several inches thick and supported by beams columns walls or the ground.

Pairs of opposing rafters were thus initially tied together by a horizontal tie. Tie beams connecting each pair of the opposite rafters. A waterproofing layer that protects the roof valleys from leaking. The space between each truss is known as a bay.