Timber frame construction
The timber frame (also a timber frame or post and beam construction ) is a common modern timber system . A special form of timber frame construction is the timber panel construction , in which the wall and ceiling elements are largely prefabricated in the factory.
In timber frame construction, a framework of vertical posts and horizontal bars serves to transfer the load. The horizontal stiffening is achieved by cladding with panel-shaped wall building materials, diagonally applied boards or via recessed struts.
This type of construction can be found in Central and Northern Europe, especially Scandinavia, but mainly in North America. There, timber frame construction is by far the predominant construction method in one or two-story residential buildings .
history
Timber frame construction is a further development of half-timbered construction that took place in the United States of America at the beginning of the 19th century .
In (North American) timber frame construction, two-inch planks (50 mm) were mainly used, which are connected via nailed, butt wood connections, instead of the traditional carpentry mortised or paneled wood connections . Even slimmer 38 mm thick planks are now being used.
This development was promoted by the advent of sawmills powered by steam engines . So one was no longer primarily dependent on single-handled beams , which were hewn from round wood with a broad ax or adze , but had easily manageable and standardized planks available. Another requirement for timber frame construction was the beginning of the mass production of nails by machine .
Compared to traditional half-timbered or block construction , less wood is required. The simple design does not require any special manual training. Transport and storage of the standardized building material can be carried out with little effort. The light construction timbers allow rapid construction progress with few workers. Since the often long periods of frost in North America did not interrupt the construction progress, timber frame construction developed into the predominant construction method there. In contrast to the densely built-up towns in Europe, the flammability of the building material was not a major disadvantage when erecting individual buildings at a distance from their neighbors.
In Central Europe, the timber frame construction was developed relatively late with the advent of prefabricated houses in the form of the timber panel construction, but so far has not been as widespread as in North America. One of the first areas of application were barracks for temporary accommodation during industrialization and railway construction. At the same time, timber frame construction has also established itself as a manual construction method.
Construction methods
The facade design can be freely selected for all construction principles. Plasters on thermal insulation composite systems , masonry cladding, external cladding made of wood, plastic or mineral panels are just a few examples.
- Post and Girt
- The construction of the early settlers in New England, with heavy corner beams ( posts ) connected by horizontal beams ( girts ).
- Balloon framing
- In the USA and Canada, this was the wooden frame construction, which had been widespread since the early 19th century, the main feature of which was the continuous wall posts across the floors, similar to the medieval post construction .
- As a support for the joist layer, a wooden plank is embedded at ceiling height, the joist layer is placed and fastened to the side of the post. Originally, the outer walls were either stiffened with recessed struts or planked diagonally with boards on the outside. The inner outer wall, inner walls and undersides of the ceiling were mostly covered with thin wooden strips, which served as a plaster base for a gypsum plaster. With the beginning of the industrial production of plasterboard in the USA from 1910 and the introduction of panel -shaped wood - based materials , these wall -building materials , which can be processed even more efficiently, were used.
- Platform framing
- Since around the end of the Second World War, this now predominant construction method emerged in North America, which is in some respects comparable to the late medieval frame construction ( floor construction ).
- In contrast to the balloon framing , the raw construction is built on a floor-by-floor basis and each completed with a platform on which the next floor is then built. The wooden supporting structure of the walls, consisting of the wall posts including the upper and lower straps, is first prefabricated lying on the respective floor, then erected and connected to one another with an additional top strap. On the outside and on the ceiling, panels made of plywood or OSB are attached, the rest is covered with plasterboard after the shell has been completed.
- All details are standardized and mostly strictly regulated in building regulations. 38 mm thick planks with just a few widths and lengths are used for the construction timber. With the beam position of the storey ceilings, so-called I-joists or prefabricated trusses are increasingly replacing the 38 mm solid wood planks that are otherwise installed on edge. As a rule, prefabricated nail plate trusses are used for the roof structure .
- The pitch of the vertical support structure is normally 16 inches (40.64 cm). 12 inches (30.48 cm) or 24 inches (60.96 cm) are also possible. The integral multiple of the grid dimension always results in the width of the building panels of 48 inches (121.92 cm). The grid dimensions of the ceilings and the roof structure can be independent of that of the walls.
- Depending on how the elements are connected to one another, a distinction is made between Timber Frame Construction and Post and Beam Construction . In Timber framing solid wood is used exclusively; the connection is made by tenons , which are secured with wooden dowels . In the case of post-and-beam construction, on the other hand, the connection is made by straight overlapping ( half-lap joint ) with hidden holders; sometimes decorative metal clips are also used. Glued laminated timber beams can also be connected by overlaying . With both methods, the house frame is so stable that no further load-bearing walls are required inside the house; as a result, very large rooms are possible there, which can have high ceilings. Timber Frame Construction is usually more expensive than Post and Beam Construction .
- Construction method in German-speaking countries
- The prevailing far timber frame construction in German-speaking countries is a modern form of jettying and comparable to the current North American platform frames , though standardization is much lower, especially in the area of the ceiling and the roof structure . In contrast to platform framing , the wood cross-sections are more massive and the grid dimensions larger. This is based on the plate size of 125 cm × 250 cm and is either 62.5 cm or 83.3 cm. Overall, the degree of prefabrication is usually high, even with manual production, so that there are hardly any differences to the wooden panel construction of the prefabricated house construction.
- The construction principle of the traditional post construction is hardly used in modern timber frame construction. Nevertheless, timber frame construction is also colloquially referred to as timber stud construction, individual walls as wooden stud walls , analogous to the term metal stud walls from drywall .
See also: prefabricated construction , panel construction
Related construction with cold-formed steel profiles
The Light Gauge Steel Framing (abbreviated: LSF ) is a frame construction derived from the North American platform framing . All load-bearing and non-load-bearing wooden profiles have been replaced by cold-formed steel profiles, comparable to those used in drywall construction. Instead of nails, self-tapping screws or rivets are used. The thin-out can sheet steel manufactured profiles also directly at the site of the wound metal strips are cold-formed in order to minimize waste.
See also
literature
- Bund Deutscher Zimmermeister (Ed.), Klaus Fritzen: Timber frame construction: Proven house building system ISBN 3871042013
- Josef Kolb: Timber construction with a system - supporting structure and layer structure of the components. ISBN 3764376139 .
Web links
Individual evidence
- ^ Encyclopedia of Chicago: Balloon Frame Construction , accessed July 17, 2013.
- ↑ Marcella Pizzi: The Invention of the Balloon Frame (PDF; 1.1 MB), accessed on July 17, 2013.
- ↑ George E. Woodward: Woodward's Country Homes , New York 1865, page 151, accessed July 17, 2013.
- ↑ post-and-girt framing. Retrieved April 19, 2020 .
- ↑ Timber Frame Vs Post And Beam Construction. Retrieved March 16, 2020 .
- ^ Canadian Sheet Steel Building Institute: LSF House Construction Handbook (2005). . Retrieved November 7, 2013
- ↑ Example of on-site manufactured steel profiles for the LSF construction . Retrieved November 7, 2013