Search results
Results from the WOW.Com Content Network
Greek: the ridge height is 1 ⁄ 9 to 1 ⁄ 7 the span (an angle of 12.5° to 16°); Roman: the ridge height is 2 ⁄ 9 to 1 ⁄ 3 the span (an angle of 24° to 34°); Common: the rafter length is 3 ⁄ 4 the span (about 48°); Gothic: the rafters equal the span (60°); and; Elizabethan: the rafters are longer than the span (more than 60°). [7]
This number gives the length of the hip or valley rafter per seventeen units of run. Difference in lengths jacks. The jack rafters lie in the same plane as the common rafter but connect the top plate (the wall) or ridge board to the hip or valley rafter respectively. Since the hip or valley rafter meets the ridge board and the common rafter at ...
For longer span rafters, building materials manufacturers have created laminated veneer lumber (LVL) rafters that can be 2–5 times longer than typical wood rafter. In the US, most wood rafters have maximum length of 20 feet (6.1 m). [5] If a longer rafter is needed, LVL is an alternative.
Hip, hipped: A hipped roof is sloped in two pairs of directions (e.g. N–S and E–W) compared to the one pair of direction (e.g. N–S or E–W) for a gable roof. Cross hipped: The result of joining two or more hip roof sections together, forming a T or L shape for the simplest forms, or any number of more complex shapes.
The "hips" and hip rafters sit on an external corner of the building and rise to the ridge. Where the building has an internal corner, a valley makes the join between the sloping surfaces (and is underlain by a valley rafter). Hip roofs have the advantage of giving a compact, solid appearance to a structure. The roof pitch (slope) may vary.
Building codes in the U.S. specify ventilation rates as a minimum of 1 sq ft (0.093 m 2) of opening per 150 sq ft (14 m 2) (1:150) with a ratio of 1:300 in some conditions. [8] Warm air rises, so ceiling insulation is designed to have a higher r-value and the insulation is often installed between the ceiling joists or rafters.
Key: 1: principal rafters, 2: collar beam, 3: arch braces. Lacking a tie beam, [ 11 ] the arch-braced (arched brace) [ 12 ] truss gives a more open look to the interior of the roof. The principal rafters are linked by a collar beam supported by a pair of arch braces, which stiffen the structure and help to transmit the weight of the roof down ...
Rafter – is one of a series of sloped structural members that extend from the ridge or hip to the wall plate, downslope perimeter or eave, and that are designed to support the roof deck and its associated loads. [30] A pair of rafters is called a couple. In home construction, rafters are normally made of wood. Exposed rafters are a feature of ...