Under Roof Beams

Built up roof beams you will need a roof beam as a nailing surface to support the rafters.

Under roof beams.

Collar ties rafter ties tension beams structural ridge beams. This freestanding structure is supported by posts or columns and the roof is made up of evenly spaced slatted beams. Once again you will need to look at your local charts and use your local snow load factor to determine the maximum span for a given wood rafter size. Or boards plywood or oriented strand board form the roof deck also called the sheeting or sheathing to support the roof covering.

The space between each truss is known as a bay. Trusses usually occur at regular intervals linked by longitudinal timbers such as purlins. Plan your pergola carefully. The inherent strength and integrity of the triangular form makes the roof a sound structure.

Some of these can support the roof and prevent ridge sagging and wall spreading. Some homeowners have noticed this term gradually worming its way into their vocabulary. Mirrored pairs of rafters meet at a ridge and are connected across the base by a ceiling joist. Pairs of opposing rafters were thus initially tied together by a horizontal tie.

A newer type of beam than the more traditional materials a composite roof beam can be made from several different materials to make the beam lighter and stronger and less prone to rotting warping or cracking. A roof beam is generally a length of wood steel or aluminum that holds up a roof meant to keep rain snow and other elements out of the house. You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths. Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads.

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. A pergola is a non traditional style roof in that it s open and provides filtered shade than protection from the elements. Their homes are typically the ones that have exposed roof beams projecting out to or beyond the roof edge framing. Heavier under purlins or purlin plates are used to support longer rafter spans.

Usually made from 1 2 inch plywood the decking closes and reinforces the roof structure and provides a nailbed for the shingles. Depending on the roof covering material either horizontal laths battens or purlins are fixed to the rafters. Roof edge or eaves edge all the boards running along the edge of the roof or eaves. These structures can look large and imposing.

For larger spans and thinner walls this can topple the walls. Rafters have a tendency to flatten under gravity thrusting outwards on the walls. Also known as a fascia. Typically the roof beam is made by nailing together a few pieces of dimensional lumber.