Timber Roof Wall Plate Size

The roof covering membrane may also require additional fixing using mechanical fasteners to prevent uplift high wind load areas.

Timber roof wall plate size.

The trimmed joist will measure 600mm minus the thickness of the joist substitute 600 for 400 450 or whatever centers you are working to. 38 x 100mm or in accordance with local practice. If you have tall joists you may need to cut a splice or seat cut on the end of the joist so it doesn t protrude above the rafters. Fixings used to connect the roof structure to the wall plate should be specified according to the roof construction and exposure of the site.

A plate in timber framing is a piece of timber upon which some considerable weight is framed hence ground plate window plate obsolete etc. As the mortar does not bond the wall plate to the wall steel straps are used to ensure that the roof structure remains secure. In scotland 100mm x 25mm wall plates should be used in long lengths butt jointed. Generally wall plates are in lengths of not less than 3 m.

Wall plates should generally be in lengths of not less than 3m but shorter lengths should extend over at least 3 joists rafters or trusses. Likewise for the trimmed joist 600mm from the outside of the wall plate. Wall plates should be joined using half lapped joints at corners and in running lengths. Wall plates are to be fixed to masonery using hardened nails 4mm in diameter x 75mm long or 50mm long wood screws if fixed into timber.

These are typically 1 2 m long with a cranked end and are fixed to the wall plate at 2 m centres. Minimum timber size will be 95mm x 35mm although this may increase for the following reasons.