It is the most universal type of construction of a roof. It can be applied at downgrades from 6 to 70 ° in one- and double-pitch roofs, at spans to 16 m. with string pieces this design differs From rafters in the way of transfer of loadings: on flooring or internal load bearing walls. The part of loadings that is why the wall of a penthouse does not demand strengthening is transferred to external walls only. There are some sorts of constructive decisions of rafters with lintels and double string pieces:
Consisting of the basic rafters (they, in turn, consist of two feet of a rafter, pairs string pieces and two columns) and private soldiers (consist only of the feet of a rafter leaning on lintels and inferior purlins). This type of construction at spans of 9-10 m does not demand strengthening transversely, but at span increase it is necessary to apply inclined braces in a plane of the basic rafters. Rigidness is transversely provided крестовыми with communications, the designs leaning against a wall of an attic floor, — carry out in houses with an inhabited penthouse. The usual height of walls of an attic floor in its bottom part makes 1,2—2 m both at flat, and at pitched roofs. It is a standard construction with a base girder, racks, raking shores and lintel. Распор, squeezing out the wall outside, is accepted by the double string pieces connecting feet of a rafter with racks;
The flat roof with lintels and string pieces — usually a ridge piece in this design leans against an attic floor wall. The given decision apply, when distance between walls of 8-9 m, and an angle of slope — 6—18 °. At the big spans to 16 m, except a ridge piece, do two intermediate. Racks of the basic design incorporate in pair string pieces. Inclined braces in a plane of rafters increase a lateral rigidity of a design and allow to reduce length of double string pieces. A similar design apply as well to single-pitch roofs.
Roof frames
Interest them has increased together with a fashion on building of frame houses. Earlier roof frames were used for flooring of industrial buildings and on private building areas did not meet almost. Now the situation has changed, and trusses are applied not only in wooden, but also in stone houses. It is the most expedient to use roof frames for double-pitch roofs with a small downgrade (14—23 °) in houses with an uninhabited attic floor with span of external walls to 12 m. advantages of roof frames — ease, simplicity of performance of repeating elements, possibility to make them on manufacture and the free organisation of an interior without internal load bearing walls and bearers In this case are obviously visible.
Longitudinal rigidness of a roof design
In each roof design rigidness in a lengthwise direction is necessary both at , and at roof operation. At installation designs need to be protected from tipping over. For this purpose right after rafter installations incorporate diagonal wind boards. They are nailed down from attic space not to prevent to stack a solar roof. As the additional amplifier of rigidness ridge pieces can serve.
Wind boards can remain in a roof design and after installation, especially if the roof abrupt, and on an attic floor is not expected premises. And at use of a solid purlin or slabs of the SMALLPOX wind boards can be removed from boards. Wind boards can run into feet of a rafter. Then they will not prevent the device of an inside lining of a mansard floor. the trellised purlin applied usually for roofs from a tile and a metal tile, cannot provide sufficient rigidness system transversely.
Consisting of the basic rafters (they, in turn, consist of two feet of a rafter, pairs string pieces and two columns) and private soldiers (consist only of the feet of a rafter leaning on lintels and inferior purlins). This type of construction at spans of 9-10 m does not demand strengthening transversely, but at span increase it is necessary to apply inclined braces in a plane of the basic rafters. Rigidness is transversely provided крестовыми with communications, the designs leaning against a wall of an attic floor, — carry out in houses with an inhabited penthouse. The usual height of walls of an attic floor in its bottom part makes 1,2—2 m both at flat, and at pitched roofs. It is a standard construction with a base girder, racks, raking shores and lintel. Распор, squeezing out the wall outside, is accepted by the double string pieces connecting feet of a rafter with racks;
The flat roof with lintels and string pieces — usually a ridge piece in this design leans against an attic floor wall. The given decision apply, when distance between walls of 8-9 m, and an angle of slope — 6—18 °. At the big spans to 16 m, except a ridge piece, do two intermediate. Racks of the basic design incorporate in pair string pieces. Inclined braces in a plane of rafters increase a lateral rigidity of a design and allow to reduce length of double string pieces. A similar design apply as well to single-pitch roofs.
Roof frames
Interest them has increased together with a fashion on building of frame houses. Earlier roof frames were used for flooring of industrial buildings and on private building areas did not meet almost. Now the situation has changed, and trusses are applied not only in wooden, but also in stone houses. It is the most expedient to use roof frames for double-pitch roofs with a small downgrade (14—23 °) in houses with an uninhabited attic floor with span of external walls to 12 m. advantages of roof frames — ease, simplicity of performance of repeating elements, possibility to make them on manufacture and the free organisation of an interior without internal load bearing walls and bearers In this case are obviously visible.
Longitudinal rigidness of a roof design
In each roof design rigidness in a lengthwise direction is necessary both at , and at roof operation. At installation designs need to be protected from tipping over. For this purpose right after rafter installations incorporate diagonal wind boards. They are nailed down from attic space not to prevent to stack a solar roof. As the additional amplifier of rigidness ridge pieces can serve.
Wind boards can remain in a roof design and after installation, especially if the roof abrupt, and on an attic floor is not expected premises. And at use of a solid purlin or slabs of the SMALLPOX wind boards can be removed from boards. Wind boards can run into feet of a rafter. Then they will not prevent the device of an inside lining of a mansard floor. the trellised purlin applied usually for roofs from a tile and a metal tile, cannot provide sufficient rigidness system transversely.
