What Timber To Use On A Flat Roof

Installing deck on a flat roof tips.

What timber to use on a flat roof.

By far the biggest advantage of using a flat roof is the expense. Of course flat roofs are not flat but have a very slight roof pitch of between 1 4 to 1 2 per foot. Many types of material used for installation run about 80 a foot which makes a flat roof extremely affordable both for the initial installation and the. C16 timber is kiln dried timber certified to comply with the criteria of strength grade c16.

Ensure that the product has been duly certified by the british board of agrément bba before it is used for your project. In the majority of cases the covering will be plywood or osb timber which is more commonly called stirling board. Osb has almost the same application and usefulness as the plywood it is made from wafers of timber rather than full sheets of veneer. Although the construction of the actual roof component of a parapet roof is almost identical to a typical pitched roof it is wise to use a greater minimum roof pitch than is recommended by the roof sheet.

Flat roof with no permanent access and altitude not exceeding 100m 0 75 kn m udl 0 9 kn point load most areas exceeding 100m but not exceeding 200m excluding parts of scotland pennines north east england refer to bs 6399 3 1 kn m udl 0 9 kn point load. When timbers are used in flat roofing they obviously need to be waterproofed so boards are normally laid across the joists and then a felt or rubber is used to cover the boards to make them waterproof. The usual recommendation is that osb 3 or osb 4 bs en 300 should be used in flat roofs. It s often chosen as the standard timber for roof extensions or joist refurbishment as it s the most cost effective internal structural timber.

From the initial building and installation to the materials most often used to cover the roof flat roofs are fairly cheap. Flat roofs of this type are usually finished in steel roof sheet and fall towards a special type of gutter called a box gutter. The basic construction of a flat roof starts with roofing timber that is laid across two upright items usually two walls. Push fit easyfix shoes at gaps of 400mm down the length of timber battens 8 per m2 recommended.

Choose what height timber batten to use paying close attention to the height of any existing door threshold. Just enough slope to drain water but also flat enough to be a problem if not constructed properly. Having a manual for warm flat roof construction with details and a summary of rules to follow helps. A cavity closer should be provided to the top of the walls to prevent fire spread and to stop damp air entering the roof space.