Post-and-beam

Timber framing and "post-and-beam" construction is a general term for building with heavy timbers rather than "dimension lumber" such as 2"x4"s. Traditional timber framing is the method of creating structures using heavy squared-off and carefully fitted and joined timbers with joints secured by large wooden pegs (larger versions of the mortise and tenon joints in furniture). It is commonplace in wooden buildings from the 19th century and earlier. The method comes from making things out of logs and tree trunks without modern high tech saws to cut lumber from the starting material stock. Using axes, adzes and draw knives, hand powered auger drill bits (bit and brace), and laborious woodworking, artisans or farmers could gradually assemble a building capable of bearing heavy weight without excessive use of interior space given over to vertical support posts. Since this building method has been used for thousands of years in many parts of the world there are many styles of historic framing. These styles are often categorized by the type of foundation, walls, how and where the beams intersect, the use of curved timbers, and the roof framing details. Three basic types of timber frames in English speaking countries are the box frame, cruck frame, and aisled frame.



The box frame

A simple timber frame made of straight vertical and horizontal pieces with a common rafter roof without purlins. The term box frame is not well defined and has been used for any kind of framing other than cruck framing. The distinction presented here is the roof load is carried by the exterior walls.

The cruck frame

A cruck is a pair of crooked or curved timbers[1] which form a bent (U.S.) or crossframe (U.K.), the individual timbers each called a blade. More than 4,000 cruck frame buildings have been recorded in the U.K. There are several types of cruck frames (more information follows in English Style below and at the main article Cruck):

  • True cruck or full cruck: blades, straight or curved, extend from ground or foundation to the ridge acting as the principal rafters. A full cruck does not need a tie beam.
  • Base cruck: tops of the blades truncated by the first transverse member such as by a tie beam.
  • Raised cruck: blades land on masonry wall, extend to ridge.
  • Middle cruck: blades land on masonry wall, truncated by collar.
  • Upper cruck: blades land on tie beam, very similar to knee rafters.
  • Jointed cruck: blades made from pieces joined near eaves in a number of ways.
  • End cruck is not a style but on the gable end of a building.


Aisled frame

Aisled frames have one or more rows of interior posts. These interior posts typically carry more structural load than the posts in the exterior walls. This is the same concept of the aisle in church buildings, sometimes called a hall church, where the center aisle is technically called a nave. However a nave is often called an aisle and three-aisled barns are common in the U.S., Netherlands and Germany. Aisled buildings are wider than the simpler box framed or cruck framed buildings and typically have purlins supporting the rafters. In northern Germany this construction is known as variations of a Ständerhaus.

Half-timbered


The term half-timbered has two meanings in building construction: 1) half-timbering is "A lattice of panels filled with a non-loadbearing material infill of brick noggin or wattle and daub (or similar methods), the frame is often exposed on the outside of the building."[2] 2) The less common meaning of the term half-timbered is found in the fourth edition of John Henry Parker's Classic Dictionary of Architecture (1873) which distinguishes full-timbered houses from half-timbered, with half timber houses having a ground floor in stone[3] or logs such as the Kluge House which was a log cabin with a timber framed second floor.

The panels between the timbers are filled-in with non-structural material that is known as infill. The earliest known type of infill was called opus craticum by the Romans which was a wattle and daub type construction.[4] Opus craticum is now confusingly applied to a Roman stone/mortar infill also. Similar methods to wattle and daub were also used and known by various names as clam staff and daub, cat-and-clay, or torchis (French) to only name three. Brick infill sometimes called nogging became the standard infill after the manufacturing of bricks made them more available and less expensive. Half-timbered walls may be covered by siding materials including plaster, weatherboarding, tiles, or slate shingles.[5]

The term half-timbering is not as old as the German name fachwerk or the French name colombage, but it is the standard English name for this style. One of the first people to publish the term half-timbered was Mary Martha Sherwood (1775–1851), who employed it in her book, The Lady of the Manor, published in several volumes from 1823 to 1829. She uses the term picturesquely: "...passing through a gate in a quickset hedge, we arrived at the porch of an old half-timbered cottage, where an aged man and woman received us."[6] By 1842, half-timbered had found its way into The Encyclopedia of Architecture by Joseph Gwilt (1784–1863). This juxtaposition of exposed timbered beams and infilled spaces created the distinctive "half-timbered", or occasionally termed, "Tudor", style, or "black-and-white".

The most ancient known half-timbered building is called the House of Opus craticum. It was buried by the eruption of Mount Vesuvius in 79 AD in Herculaneum, Italy. Opus craticum was mentioned by Vitruvius in his books on architecture as a timber frame with wattlework infill[7] however the same term is used to describe timber frames with an infill of stone rubble laid in mortar the Romans called Opus incertum.[8]

To finish the walls the spaces between the timbers, called panels or in German Fächer, were often infilled with a variety of earth based coatings suspended on sticks or wattles as in wattel and daub or bousillage, fired brick, un-fired brick such as adobe or mudbrick, stones sometimes called pierrotage, planks as in the German standerbohlenbau, timbers as in standerblockbau, or rarely cob without any wooden support.[9] The wall surface on the interior were often “ceiled” with wainscoting and plasteed for warmth and appearance.

Wattle and daub was the most common infill in ancient times. The sticks were not always technically wattlework (woven) but also individual sticks installed vertically, horizontally or at an angle into holes or grooves in the framing. The coating of daub has many recipes but generally was a mixture of clay and chalk with a binder such as grass or straw and water or urine.[10] When the manufacturing of bricks increased, brick infill replaced the less durable infills and became more common. Stone laid in mortar as an infill was used in areas where stone rubble and mortar were available.

The infill may be covered by other materials, including plaster, weatherboarding or tiles.[5] or left exposed. When left exposed both the framing and infill were sometimes done in a decorative manner. Germany is famous for its decorative half-timbering and the figures sometimes have names and meanings. The decorative manner of half-timbering is promoted in Germany by the German fachwerk road, several planned routes people can drive to see notable examples of fachwerk buildings.

Gallery of infill types:

Gallery of some named figures and decorations:

The collection of elements in half timbering are sometimes given specific names:

Structure



Traditional timber framing is the method of creating framed structures of heavy timber jointed together with various joints, commonly and originally with lap jointing, and then later pegged mortise and tenon joints. Diagonal bracing is used to prevent "racking", or movement of structural vertical beams or posts.[11]

Originally, German (and other) master carpenters would peg the joints with allowance of approximately an inch (25 mm), enough room for the wood to move as it seasoned, then cut the pegs, and drive the beam home fully into its socket.

To cope with variable sizes and shapes of hewn (by adze or axe) and sawn timbers, two main carpentry methods were employed: scribe carpentry and square rule carpentry.

Scribing or coping was used throughout Europe, especially from the 12th century to the 19th century and subsequently imported to North America where it was common into the early 19th century. In a scribe frame, timber sockets are fashioned or "tailor-made" to fit their corresponding timbers; thus each timber piece must be numbered (or "scribed").

Square-rule carpentry was developed in New England in the 18th century. It used housed joints in main timbers to allow for interchangeable braces and girts. Today, standardised timber sizing means that timber framing can be incorporated into mass-production methods as per the joinery industry, especially where timber is cut by precision computer numerical control (CNC) machinery.

Jetties

A jetty is an upper floor which requires a structural cantilevered horizontal beam called a bressummer or jetty bressummer to bear the weight of the new wall, projecting outward from the preceding floor or storey.

In an era when houses were taxed with respect to ground-floor area (square footage) extensive jettying was employed to create higher storeys of greater area.

In the city of York in the United Kingdom, the famous street known as The Shambles exemplifies this, where jettied houses seem to almost touch above the street.

Timbers

Historically, the timbers would have been hewn square using a felling axe and then surface-finished with a broadaxe. If required, smaller timbers were ripsawn from the hewn baulks using pitsaws or frame saws. Today it is more common for timbers to be bandsawn, and the timbers may sometimes be machine-planed on all four sides.

The vertical timbers include:

The horizontal timbers include:

  • sill-beams (also called ground-sills or sole-pieces, at the bottom of a wall into which posts and studs are fitted using tenons),
  • noggin-pieces (the horizontal timbers forming the tops and bottoms of the frames of infill panels),
  • wall-plates (at the top of timber-framed walls that support the trusses and joists of the roof).

When jettying, horizontal elements can include:

  • the jetty bressummer (or breastsummer): the main sill (horizontal piece) on which the projecting wall above rests and which stretches across the whole width of the jetty wall. The bressummer is itself cantilevered forward, beyond the wall below it.
  • the dragon-beam which runs diagonally from one corner to another, and supports the corner posts above and supported by the corner posts below.
  • the jetty beams or joists which conform floor dimensions above but are at right angles to the jetty-plates that conform to the shorter dimensions of "roof" of the floor below. Jetty beams are morticed at 45° into the sides of the dragon beams. They are the main constituents of the cantilever system and determine how far the jetty projects
  • the jetty-plates, designed to carry the jetty beams. The jetty plates themselves are supported by the corner posts of the recessed floor below.

The sloping timbers include:

  • trusses (the slanting timbers forming the triangular framework at gables and roof),
  • braces (slanting beams giving extra support between horizontal or vertical members of the timber frame),
  • herringbone bracing (a decorative and supporting style of frame, usually at 45° to the upright and horizontal directions of the frame).

Modern features


In the United States and Canada, timber-frame construction has been revived since the 1970s and is now experiencing a thriving renaissance of the ancient skills. This is largely due to such practitioners as Steve Chappell, Jack Sobon, and Tedd Benson, who studied old plans and techniques and revived a long-neglected technique. Once a handcrafted skill passed down, timber-frame construction has now been modernized with the help of modern industrial tools such as the CNC machines. These machines and mass-production techniques have assisted growth and made for more affordable frames and shorter lead-times for projects.

Timber-framed structures differ from conventional wood-framed buildings in several ways. Timber framing uses fewer, larger wooden members, commonly timbers in the range of 15 to 30 cm (6" to 12"), while common wood framing uses many more timbers with dimensions usually in the 5 to 25 cm (2" to 10") range. The methods of fastening the frame members also differ. In conventional framing, the members are joined using nails or other mechanical fasteners, whereas timber framing uses the traditional mortice and tenon or more complex joints that are usually fastened using only wooden pegs.[12] Modern complex structures and timber trusses often incorporate steel joinery such as gusset plates, for both structural and architectural purposes.

Recently, it has become common practice to enclose the timber structure entirely in manufactured panels such as SIPs (Structural Insulated Panels). Although the timbers can only be seen from inside the building when so enclosed, construction is less complex and insulation is greater than in traditional timber building. Structural Insulated Panel construction uses composite members consisting of "an insulating foam core sandwiched between two structural facings, typically oriented strand board," according to the Structural Insulated Panel Association.[13] SIPs reduce dependency on bracing and auxiliary members, because the panels span considerable distances and add rigidity to the basic timber frame.

An alternate construction method is with concrete flooring with extensive use of glass. This allows a very solid construction combined with open architecture. Some firms have specialized in industrial prefabrication of such residential and light commercial structures such as Huf Haus as Low-energy houses or – dependent on location – Zero-energy buildings.

Straw-bale construction is another alternative where straw bales are stacked for non-loadbearing infill with various finishes applied to the interior and exterior such as stucco and plaster. This appeals to the traditionalist and the environmentalist as this is using "found" materials to build.

Mudbricks also called adobe are sometimes used to fill in timber frame structures. They can be made on site and offer exceptional fire resistance. Such buildings must be designed to accommodate the poor thermal insulating properties of mudbrick however, and usually have deep eaves or a verandah on 4 sides for weather protection.

History and traditions

The techniques used in timber framing date back to Neolithic times, and have been used in many parts of the world during various periods such as ancient Japan, continental Europe as well as Neolithic Denmark, England, France, Germany parts of the Roman Empire and Scotland.[14] The timber framing technique has historically been popular in climate zones which favour deciduous hardwood trees, such as oak. Its most northernmost areas are Baltic countries and southern Sweden. Timber framing is rare in Russia, Finland, northern Sweden, and Norway, where tall and straight lumber, such as pine and spruce, is readily available and log houses were favoured instead.

Half-timbered construction in the Northern European vernacular building style is characteristic of medieval and early modern Denmark, England, Germany and parts of France and Switzerland where timber was in good supply yet stone and associated skills to dress the stonework were in short supply. In half-timbered construction timbers that were riven (split) in half provided the complete skeletal framing of the building.

Some Roman carpentry preserved in anoxic layers of clay at Romano-British villa sites demonstrate that sophisticated Roman carpentry had all the necessary techniques for this construction. The earliest surviving (French) half-timbered buildings date from the 12th century.

Important resources for the study and appreciation of historic building methods are open-air museums.

Topping out ceremony

The topping out ceremony is a builders' rite, an ancient tradition thought to have originated in Scandinavia by 700 AD.[15] In the U.S. a bough or small tree is attached to the peak of the timber frame after the frame is complete as a celebration. Historically it was common for the master carpenter to give a speech, make a toast, and then break the glass. In Northern Europe it is more common to use a wreath made for the occasion rather than a bough. In Japan the "ridge raising" ceremony is called the jotoshiki and is a religious ceremony.[16] In Germany it is called the Richtfest (German language site)

Carpenters marks

"Carpenters marks" is a general term for markings left on the timbers of a wooden building during construction.

  • Assembly or marriage marks and were used to identify the individual timbers. Assembly marks include numbering to identify the pieces of the frame. The numbering can be similar to Roman numerals except the number four is IIII and nine is VIIII. These marks are chiseled, cut with a race knife (a tool to cut lines and circles in wood), or saw cuts. The numbering can also be in Arabic numerals which are often written with a red grease pencil or crayon. German and French carpenters made some unique marks. (Abbundzeichen (German assembly marks)).
  • Layout marks identify the locations to cut joints and bore peg holes. Also carpenters marked the location on a timber where they leveled the timber as a part of the building process are called "level lines" and sometimes made a mark two feet from a critical location called a "two foot mark". These marks are typically scratched on the timber with an awl-like tool and later in the 19th century they started using pencils to make layout marks.
  • Occasionally carpenters or owners marked a date and/or their initials in the wood.
  • Boards on the building may have "tally marks" cut into them which were numbers used to keep track of quantities of lumber.
  • Other markings in old buildings are called "ritual marks" which were often signs the occupants felt would protect them from harm.

Tools

Many historic hand tools used by timber framers for thousands of years have similarities but vary in shape. Electrically powered tools first became available in the 1920s in the U.S. and continue to evolve. See the list of timber framing tools for basic descriptions and images of unusual tools (The list is incomplete at this time).

British tradition

Some of the earliest known timber houses in Europe have been found in Scotland and England, dating to Neolithic times; Balbridie and Fengate are some of the rare examples of these constructions.

Molded plaster ornamentation, pargetting[17] further enriched some English Tudor architecture houses. Half-timbering is characteristic of English vernacular architecture in East Anglia,[18] Warwickshire,[19][20] Worcestershire,[21] Herefordshire,[22][23] Shropshire,[24][25] and Cheshire,[26] where one of the most elaborate surviving English examples of half-timbered construction is Little Moreton Hall.[27]

In South Yorkshire, the oldest timber house in Sheffield, the "Bishops' House" (c. 1500), shows traditional half-timbered construction.

In the Weald of Kent and Sussex,[28] the half-timbered structure of the Wealden hall house,[29] consisted of an open hall with bays on either side and often jettied upper floors.

Half-timbered construction traveled with British colonists to North America in the early 17th century but was soon abandoned in New England and the mid-Atlantic colonies for clapboard facings (an East Anglia tradition). The original English colonial settlements, such as Plymouth, Massachusetts and Jamestown, Virginia had timber-framed buildings, rather than the log cabins often associated with the American frontier. Living history programs demonstrating the building technique are available at both these locations.

Many of the surviving streets lined with almost touching houses are known as The Shambles and are very popular tourist attractions.

English Styles

Historic timber frame construction in England (and the rest of the United Kingdom) showed regional variation [30] which has been divided into "eastern school", "western school", and the "northern school", although the characteristic types of framing in these schools can be found in the other regions (except the northern school).[31] A characteristic of the eastern school is close studding which is a half-timbering style of many studs spaced about the width of the studs apart (for example six inch studs spaced six inches apart) until the middle of the 16th century and sometimes wider spacing after that time. Close studding was an elite style found mostly on expensive buildings. A principal style of the western school is the use of square panels of roughly equal size and decorative framing utilizing many shapes such as lozenges, stars, crosses, quatrefoils, cusps and many other shapes.[31] The northern school sometimes used posts which landed on the foundation rather than on a sill beam, the sill joining to the sides of the posts and called an interrupted sill. Another northern style was to use close studding but in a herring-bone or chevron pattern.[31]

As houses were modified to cope with changing demands there sometimes were a combination of styles within a single timer frame construction.[32] The major types of historic framing in England are 'cruck frame',[32] box frame,[32] and aisled construction. From the box frame, more complex framed buildings such as the Wealden House and Jettied house developed.

The cruck frame design is amongst the earliest, and was [32] in use by the early 13th century, with its use continuing to the present day, although rarely after the 18th century.[32] Since the 18th century however, many existing cruck structures have been modified, with the original cruck framework becoming hidden. Aisled barns are of two or three aisled types, the oldest surviving aisled barn being the barley barn at Cressing Temple[31] dated to 1205-1235.[33]

Jettying was introduced in the 13th century and continued to be used through the 16th century.[31]

English construction became influenced by the general deforestation of the island. Longer, straight beams became unavailable and more small pieces had to be used. Important resources for the study of historic building methods in the U. K. are open air museums.

French tradition

Elaborately half-timbered houses of the 13th through 18th centuries still remain in Bourges, Troyes, Rouen, Thiers, Dinan, Rennes, and many other cities, except in Provence and Corsica. Timber framing in French is known colloquially as pan de bois and half-timbering as: colombage.

The Normandy tradition features two techniques: frameworks were built of four evenly spaced regularly hewn timbers set into the ground (poteau en terre) or into a continuous wooden sill (poteau du sole) and mortised at the top into the plate. The openings were filled with many materials including mud and straw, wattle and daub, or horsehair and gypsum.[34]

Basque tradition

Most traditional Basque buildings with half-timbering elements are detached farm houses (in Basque: baserriak). Their upper floors were built with jettied box frames in close studding. In the oldest farmsteads and, if existing, in the third floor the walls were sometimes covered with vertical weatherboards. Big holes were left in the gable of the main façade for ventilation. The wooden beams were painted over, mostly in dark red. The vacancies were filled in with wattle and daub or rubble laid in a clay mortar and then plastered over with white chalk or nogged with bricks. Although the entire supporting structure is made of wood, the timbering is only visible on the main façade, which is generally oriented to the southeast.

Although the typical Basque house is now mostly associated with half-timbering, the outer walls and the fire-walls were built in masonry (rubble stone, bricks or, ideally, ashlars) whenever it could be afforded. Timber was a sign of poverty. Oak-wood was cheaper than masonry : that is why, when the money was running out, the upper floor walls were mostly built timbered. Extant baserriak with half-timbered upper-floor façades were built from the 15th to 19th centuries and are found in all Basque regions with oceanic climate, except in Zuberoa (Soule), but are concentrated in Lapurdi (Labourd).

Some medieval Basque tower houses (dorretxeak) feature an overhanged upper floor in half-timbering.[35]

To a lesser extent timbered houses are also found in villages and towns as row houses, as the photo from the Uztaritz village shows.

Currently, it has again become popular to build houses resembling old Basque farmsteads, with more or less respect for the principles of traditional half-timbered building.[36]

German tradition (Fachwerkhäuser)

Germany has several styles of timber framing, but probably the greatest number of half-timbered buildings in the world are to be found in Germany and in Alsace (France). There are many small towns which escaped both war damage and modernisation and consist mainly, or even entirely, of half-timbered houses.


The German Timber-Frame Road connects towns with remarkable fachwerk. It crosses Germany with sections in Lower Saxony, Saxony-Anhalt, Hesse, Thuringia, Bavaria, and Baden-Württemberg.[11][37]

Some of the more prominent towns (among many) include: Quedlinburg, a UNESCO listed town, which has over 1200 half-timbered houses spanning five centuries; Goslar, another UNESCO listed town; Hanau-Steinheim (the city of the Brothers Grimm); Bad Urach; Eppingen ("Romance city" with a half-timbered church dating from 1320); Mosbach; Vaihingen an der Enz with a UNESCO-listed Celtic abbey and monastery; Schorndorf (birthplace of Gottlieb Daimler); Calw; Celle; and Biberach an der Riß with both the largest medieval complex, the Holy Spirit Hospital and the oldest Southern German building, now the Museum of Weavers, dated to 1318.

German fachwerk building styles are extremely varied with a huge number of carpentry techniques which are highly regionalised. German planning laws for the preservation of buildings and regional architecture preservation dictate that a half-timbered house must be authentic to regional or even city-specific designs before being accepted.[38][39]

A brief overview of styles follows, as a full inclusion of all styles is impossible.

In general the northern states have fachwerk very similar to that of the nearby Netherlands and England while the more southerly states (most notably Bavaria and Switzerland) have more decoration using timber because of greater forest reserves in those areas.

The German fachwerkhaus usually has a foundation of stone, or sometimes brick, perhaps up to several feet (a couple of metres) high, which the timber framework is mortised into or, more rarely, supports an irregular wooden sill.

The three main forms may divided geographically:

  • West Central Germany and Franconia:
    • In West Central German and Franconian timber-work houses (particularly in the Central Rhine and Moselle): the windows most commonly lie between the rails of the sills and lintels.
  • Northern Germany and East Central Germany (also very similar style to Poland):
    • In Saxony and around the Harz foothills, angle braces often form fully extended triangles.
    • Lower Saxon houses have a joist for every post.
    • Holstein fachwerk houses are famed for their massive 12-inch (30 cm) beams.
  • Southern Germany including the Black and Bohemian Forests
    • In Swabia, Württemberg, Alsace, and Switzerland, the use of the lap-joint is thought to be the earliest method of connecting the wall plates and tie beams and is particularly identified with Swabia. A later innovation (also pioneered in Swabia) was the use of tenons — builders left timbers to season which were held in place by wooden pegs (i.e., tenons). The timbers were initially placed with the tenons left an inch or two out of intended position and later driven home after becoming fully seasoned.

The most characteristic feature is the spacing between the posts and the high placement of windows. Panels are enclosed by a sill, posts and a plate and are crossed by two rails between which the windows are placed—like "two eyes peering out".[38][39]

In addition there is a myriad of regional scrollwork and fretwork designs of the non-loadbearing large timbers (braces) peculiar to particularly wealthy towns or cities.

A unique timber frame house type can be found in the region where borders of Germany, the Czech Republic and Poland meet - it is called the Upper Lusatian house (Umgebindehaus, translates as round-framed house). This type has a timber frame surrounding a log structure on part of the ground floor.[40]

The German Timber-Frame Road (Deutsche Fachwerkstraße) is a tourist route that links places containing picturesque half-timbered buildings. It is more than 2 000 km long and stretches across the states of Lower Saxony, Saxony-Anhalt, Hesse, Thuringia, Bavaria, and Baden-Württemberg.

Poland

Poland has a strong history of log building. The Germans are credited[by whom?] with introducing fachwerk to Poland. A distinctive feature on houses associated with mostly Mennonite immigrant groups from Frisia and the Netherlands, known as the Olędrzy, is called an arcade house (dom podcieniowy).

Discussed in the section above on Germany, Poland shares the unique house type named for its timber-framed structure, the umgebinde house.

Another world-class type of wooden building Poland shares with some neighboring countries is its wooden church buildings.

Spain

The Spanish follow the Mediterranean forms of architecture with stone walls and shallow a roof pitch. Timber framing is often of the post and lintel style.

Switzerland

Switzerland has many styles of timber framing which overlap with its neighboring countries.

Belgium

Nowadays, timber framing mostly subsists in the provinces of Limburg, Liège and Luxemburg. In urban areas, one used to build the ground floor in stone and the upper floors in timber framing. Also, as timber framing was seen as a cheaper way of building, often the visible structures of noble houses were in stone and bricks, and the invisible or lateral walls in timber framing. The open air museums of Bokrijk and Saint-Hubert (Fourneau Saint-Michel) show many examples of Belgian timber framing. Many post and beam houses subsists in cities and villages, but, unlike France, the United Kingdom and Germany, there are few fully timber framed cityscapes.

Sweden

The Swedish mostly built log houses but they do have traditions of several types of timber framing: Some of the following links are written in Swedish. Most of the half-timbered houses in Sweden were built during the Danish time and a located in what until 1658 used to be Danish territory in southern Sweden, primarily in the province Skåne.

  • Swedish half timbering is called "korsvirke".
  • Stave construction is called "stavverk". Scandinavia is famous for its ancient Stave churchs. Stave construction is a traditional timber frame with walls of vertical planks, the posts and planks landing in a sill on a foundation. Similar construction with earthfast posts is called "stolpteknik". and Palisade construction where many vertical wall timbers or planks have their feet buried in the ground called Post in ground or earthfast construction is called "palissadteknik". (see also Palisade church)
  • Swedish plank-frame construction is called skiftesverk. This is a traditional timber frame with walls of horizontal planks.

Norway

Norway has at least two significant types of timber framed structures: 1) The stave church and 2) grindverk. The term stave church essentially means a framed church, a distinction made in a region where log building is common. All but one surviving stave church buildings are in Norway. Replicas of stave churches and other Norwegian building types have been reproduced such as at the Scandinavian Heritage Park in North Dakota, U.S.A.

Grindverk translates as bent construction but what makes the Norwegian type of bent construction important is this type of framing uses no mortise and tenon joints and archaeological excavations have uncovered similar wooden joints from over 3,000 years ago suggesting this type of framing is an ancient, unbroken tradition. Grindverk buildings are only found on part of the western coast of Norway and is mostly found in boathouses and barns. There is not currently an article in English about grindverk framing but in Norwegian World Heritage Encyclopedia is here.[41]

Netherlands

The

Americas

Most "haft-timbered" houses existing in Missouri, Pennsylvania (ethnically, the Amish are German) and Texas were built by German settlers.[34] Old Salem North Carolina has fine examples of German fachwerk buildings.[44] Many are still present in Colonia Tovar, (Venezuela), Santa Catarina, and Rio Grande do Sul,(Brazil), where Germans settled. Later, they chose more suitable building materials for local conditions (most likely because of the great problem of tropical termites.)

New France

In the historical region of North America known as New France the style called colombage pierroté in Quebec as well other areas of Canada was half-timbered construction with infilled stone and rubble is simply called colombage in France. The style had its origins in Normandy and was brought to Canada by very early Norman settlers. The Men's House at Lower Fort Garry is a good example of colombage pierroté. The walls of such buildings were often covered over with clapboards to protect the infill from erosion. Naturally, this required frequent maintenance and the style was abandoned as a building method in the 18th century in Québec. For the same reasons, half-timbering in New England, which was originally employed by the English settlers, fell out of favour soon after the colonies had become established.

Poteaux-en-terre (posts in ground) is a type of timber framing with the many vertical posts or studs buried in the ground called Post in ground or "earthfast" construction. The tops of the posts were joined to a beam. The spaces between the posts were filled in with Bousillage or Pierrotage.

poteaux-sur-sol (posts on a sill) is a general term for any kind of framing on a sill however sometimes specifically refers to "vertical log construction" like poteaux-en-terre placed on sills with the spaces between the timbers infilled.

Piece-sur-piece also known as Post-and-plank style or "corner post construction" (and many other names) in which wood is used both for the frame and horizontal infill; for this reason it may be incorrect to call it "half-timbering". It is sometimes a blend of framing and log building with two styles: the horizontal pieces fit into groves in the posts and can slide up and down or the horizontal pieces fit into individual mortises in the posts and are pegged and the gaps between the pieces chinked (filled in with stones or chips of wood covered with mud or moss briefly discussed in Log cabin.)

This technique of a timber frame walls filled in with horizontal planks or logs proved better suited to the harsh climates of Québec and Acadia, which at the same time had abundant wood. It became very popular throughout New France, as far afield as southern Louisiana. The Hudson's Bay Company used this technique for many of its trading posts and this style of framing becoming know as Hudson Bay style or Hudson Bay corners. Also used by the Red River Colony this style also became known as "Red River Framing". “The support of horizontal timbers by corner posts is an old form of construction in Europe. It was apparently carried across much of the continent from Silesia by the Lausitz urnfield culture in the late Bronze Age.”[45] Similar building techniques are apparently not found in France[46] but exist in Germany and Switzerland known as Bohlenstanderbau when planks are used or blockstanderbau when beams are used as the infill. In Sweden known as sleppvegg or skiftesverk and in Denmark as bulhus.

A particularly interesting example in the U.S. is the Golden Plough Tavern (c. 1741), York, York County, PA, which has the ground level of corner-post construction with the second floor of fachwerk (half timbered) and was built for a German with other Germanic features.[47]

Settlers in New France also built horizontal log, brick and stone buildings.

New Netherland

Characteristics of traditional timber framing in the parts of the U.S. formerly known as New Netherland are H-framing also known as dropped-tie framing in the U.S. and the similar anchor beam framing as found in the New World Dutch barn.

New England

Some time periods/regions within New England contain certain framing elements such as common purlin roofs, five sided ridge beams, plank-frame construction and plank-wall construction. The English barn always contains an "English tying joint" and the later New England style barn were built using bents.

Japanese

Japanese timber framing is believed to be descended from Chinese framing (see Ancient Chinese wooden architecture). Asian framing is significantly different than western framing is the predominant use of post and lintel framing and an almost complete lack of diagonal bracing.

Revival styles in later centuries


When half-timbering regained popularity in Britain after 1860 in the various revival styles, such as the Queen Anne style houses by Richard Norman Shaw and others, it was often used to evoke a "Tudor" atmosphere (see Tudorbethan), though in Tudor times half-timbering had begun to look rustic and was increasingly limited to village houses (illustration, above left).

In 1912, Allen W. Jackson published The Half-Timber House: Its Origin, Design, Modern Plan, and Construction, and rambling half-timbered beach houses appeared on dune-front properties in Rhode Island or under palm-lined drives of Beverly Hills. During the 1920s increasingly minimal gestures towards some half-timbering in commercial speculative house-building saw the fashion diminish.

In the revival styles, such as Tudorbethan (Mock Tudor), the half-timbered appearance is superimposed on the brickwork or other material as an outside decorative façade rather than forming the main frame that supports the structure.

The style was used in many of the homes built in Lake Mohawk, New Jersey as well as all of the clubhouse, shops, and marina.

For information about "roundwood framing" see the book Roundwood Timber Framing:Building Naturally Using Local Resources by Ben Law (East Meon, Hampshire: Permanent Publications ; 2010. ISBN 1856230414)

Advantages

The use of timber framing in buildings offers various aesthetic and structural benefits, as the timber frame lends itself to open plan designs and allows for complete enclosure in effective insulation for energy efficiency.

In modern construction timber-frame structure offers many benefits:

  • it is rapidly erected
  • it lends itself well to prefabrication, modular construction and mass-production
  • lends well to pre-fitting the frame usually in bent or wall-sections that are aligned with jig. This allows faster erection on site and more precise alignments. Such pre-fitting in the shop is independent of a machine or hand-cut production line. Valley and hip timbers are not typically pre-fitted.
  • an "average"-sized timber-frame home can be erected within 2 to 3 days.
  • the frame can be encased with SIPs for the drying in: that is, ready for windows, mechanical systems, and roofing.
  • it can be tailored to suit customer tastes and creativity such as carvings or incorporation of heirloom structures such as barns etc.
  • it can use recycled or otherwise discarded timbers
  • it offers some structural benefits as the timber frame, if properly engineered, lends itself to better seismic survivability [49] Consequentially, there are lots of old half-timbered houses which still stand despite the foundation having partially caved in over the centuries.
  • The generally larger spaces between the frames enable greater flexibility in placing and re-locating windows and doors during and after construction, with less concern over structural implications and the need for heavy lintels.

In North America, heavy timber construction is classified Building Code Type IV: a special class reserved for timber framing which recognizes the inherent fire resistance of large timber and its ability to retain structural capacity in fire situations. In many cases this classification can eliminate the need and expense of fire sprinklers in public buildings.[50]

Disadvantages

Traditional or historic structures

In terms of the traditional half-timber or fachwerkhaus there are maybe more disadvantages than advantages today. Such houses are notoriously expensive to maintain let alone renovate and restore, most commonly owing to local regulations that do not allow divergence from the original, modification or incorporation of modern materials. Additionally, in such nations as Germany, where energy efficiency is highly regulated, the renovated building may be required to meet modern energy efficiencies, if it is to be used as a residential or commercial structure (museums and significant historic buildings have no semi-permanent habitade exempt). Many framework houses of significance are treated merely to preserve, rather than render inhabitable — most especially as the required heavy insecticidal fumigation is highly poisonous.

In some cases, it is more economical to build anew using authentic techniques and correct period materials than restore. One major problem with older structures is the phenomenon known as mechano-sorptive creep or slanting: where wood beams absorb moisture whilst under compression or tension strains and deform, shift position or both. This is a major structural issue as the house may deviate several degrees from perpendicular to its foundations (in the x-axis, y-axis and even z-axis) and thus be unsafe and unstable or so out of square it is extremely costly to remedy.[51]

A summary of problems with Fachwerkhäuser or half-timbered houses includes the following, though many can be avoided by intelligent design and application of suitable paints and surface treatments and routine maintenance. Often, though when dealing with a structure of a century or more old, it is too late.[42]

  • "slanting"- thermo-mechanical (weather-seasonally induced) and mechano-sorptive (moisture induced) creep of wood in tension and compression.[51]
  • poor prevention of capillary movement of water within any exposed timber, leading to afore-described creep, or rot
  • eaves that are too narrow or non-existent (thus allowing total exposure to rain and snow)
  • too much exterior detailing that does not allow adequate rainwater run-off
  • timber ends, joints and corners poorly protected through coatings, shape or position
  • non-bevelled vertical beams (posts and clapboards) allow water absorption and retention through capillary action.
  • surface point or coatings allowed to deteriorate
  • traditional gypsum, or wattle and daub containing organic materials (animal hair, straw, manure) which then decompose.
  • in both porteaux en terre and porteaux du sole insect, fungus or bacterial decomposition.
  • rot including dry rot.
  • infestation of xylophagous pest organisms such as (very common in Europe) the Anobiidae family particularly the common furniture beetle, termites, cockroaches, powderpost beetles, mice and rats (quite famously so in many children's stories).
  • Noise from footsteps in adjacent rooms above, below, and on the same floor in such buildings can be quite audible. This is often resolved with built-up floor systems involving clever sound-isolation and absorption techniques, and at the same time providing passage space for plumbing, wiring and even heating and cooling equipment.
  • Other fungi that are non-destructive to the wood, but are harmful to humans such as black mold. These fungi may also thrive on many "modern" building materials.
  • Wood burns more readily than some other materials, making timber-frame buildings somewhat more susceptible to fire damage, although this idea is not universally accepted: Since the cross-sectional dimensions of many structural members exceed 15 cm × 15 cm (6" × 6"), timber-frame structures benefit from the unique properties of large timbers, which char on the outside forming an insulated layer that protects the rest of the beam from burning.[52][53]
  • prior flood or soil subsidence damage

See also

Notes

References

  • Richard Harris, Discovering Timber-framed Buildings (3rd rev. ed.), Shire Publications, 1993, ISBN 0-7478-0215-7.

Further reading

English tradition
  • A good introductory book on carpentry and joinery from 1898 in London, England is titled Carpentry & Joinery by Frederick G. Webber and is a free ebook in the public domain: ISBN 9781246034189.

External links

  • Buffalo (New York) as an architectural museum: Half-timber in a variety of North American revival styles
  • History & Construction of Medieval Timber-framed Houses in England & Wales A comprehensive outline with many pictures and links
  • Timber Engineering Reference
  • German Timberframing friends
  • Virtual Tour an American Modern Day Timber Frame Home
  • Carpenters from Europe and Beyond Carpenters at work in Europe and examples of wood architecture, such as timber-frame houses.
  • Black & White Houses a site dedicated to ancient timber-frame buildings, with slideshows and information.
  • Online Collection of Timber Frame Details Highlighting the various joints and joinery of the craft.
  • UNESCO on Chinese timber framing
  • UNESCO on Korean timber framing
  • Four minute video about the Zafimaniry peoples in Madagascar, including timber framing
  • The Expressive Capacity of the Timber Frame by Brit Andresen
  • Glossary of timber framing terms in French

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