Roof Construction Timber Sizes

The following tables give details of the allowable spans and spacing for some of the more common timber sizes used in traditional roofing construction.

Roof construction timber sizes.

Modern timber roofs are mostly framed with pairs of common rafters or prefabricated wooden trusses fastened together with truss connector plates timber framed and historic buildings may be framed with principal rafters or timber roof trusses roofs are also designated as warm or cold roof depending on how they are designed and built with regard to thermal building insulation and ventilation. Building control guidance note subject ceilings and flat roofs timber sizes and construction details 09 issued 01 04 13 rev page 1 of 2 the following tables give details of the allowable spans and spacing for some of the more common timber sizes used in ceiling and flat roof construction. All the figures are based on roofing tiles or slates laid on timber laths over sarking felt. Maximum clear span of flat roof joists in metres for sc3 timber spacing between joists size of roof joist 400mm 450mm 600mm 47 x 97 1 84 1 81 1 74 47 x 120 2 43 2 39 2 27.

For solid timber members in floors ceilings and roofs for dwellings and various companies do online calculation software. It s considered heavy timber when. The minimum sizes are 6 x 8 for a column supporting a roof 8 x 8 for a column supporting a floor 6 x 10 for a floor beam 8 x 8 for a roof truss member 4 x 6 for a roof beam 3 1 finish floor decking 2 roof decking according to the. Timber has been the traditional material for building roofs as far back as early saxon times and beyond.

Trada a trade association with a strong reputation for research and publication on all things timber have published span tables in a softback book called eurocode 5 span tables. All figures are based on. It is still the roof material of choice for housebuilders and self builders irrespective of whether they are building in traditional or contemporary styles or whether they are creating pitched or flat roofs. Roof framing in this chapter we will introduce you to the fundamentals of roof design and construction.

Timber roof designing buildings wiki share your construction industry knowledge. So 552 3 6 153 pcs of 2 by 2 timber to buy in the market for ceiling noggins. Wall plate is the timber wood that are placed on top of blocks or roof beams as the case may apply so for the fastest way to calculate this is to add the entire walls length and divide by 3 6m to know the numbers of pieces you need. But before discussing roof framing we will first review some basic terms and definitions used in roof construction.

It builds on knowledge and skills acquired during the first stage which should be revised and practiced throughout the course. However for practical purposes the self builder will still find the span tables in the old. Tafe nsw construction transport division 1 timber roof trusses timber roof trusses this text introduces subject matter related to the manufacture and installation of timber roof trusses.