Prefabricated trusses which are delivered to site and erected.
Timber pitched roof construction details.
Clay and concrete tiles have retaining nibs on the back of the tile which rest on the wooden lath.
Building a pitched roof prefabricated trusses the latter stages of construction felt battening tiling remain the same regardless of the framing method used.
A truss roof using factory made trusses which are delivered to site complete and just erected.
Read part 2 pitched roof construction.
The two basic construction methods of pitched roofs are.
Roofs with pitches of 10 to 20 are often called low pitched roofs and special considerations need to be made particularly on the overlap between tiles to avoid water being blown into the roof by the wind.
A traditional method of cutting timber on site and building up the roof using rafters joists purlins ridge.
The most commonly used types of pitched roof construction are the gable the hip the intersecting and the shed or lean to.
The following tables give details of the allowable spans and spacing for some of the more common timber sizes used in traditional roofing construction.
Joists are placed on edge spaced at 400 600mm centres supported by external and internal load bearing walls.
Timber is a heavy material that adds strength to your roof but comes at quite the cost.
Ventilated batten void warm roof gable 3 06 timber frame timber flat roof 3 07 timber frame timber flat roof with parapet 3 08 timber frame lintel at window head 3 09 timber frame windows and doors jambs and cills specification within an example should 3 10 timber frame ground bearing floor insulation above slab 3 11 timber frame ground bearing floor insulation below slab.
Each truss is lifted into position and fixed to the plate.
There are two basic methods of pitched roof construction.
A cut roof this is the traditional method of cutting the timber on site and building up the roof using rafters ridge boards joists and purlins etc the exact details being determined by the size of roof size of timbers etc.
Pitched roof timber sizes.
Timber pitched rooftop construction details focus on the timber construction that is commonly used in most roofing constructions.
Pitched roof detail the way that the tile is held on the roof differs slightly according to the material used.
Trada and approved document part a give guidance on sizes of joists for flat roofs relating to spans and loading.
An example of each is shown in figure 2 1.
When constructing a pitched rooftop with timber this can be an incredibly labor intensive build.
