Timber Frame

Timber frame is a way of building in which a skeleton of heavy, squared wooden posts and beams carries the loads of a structure, while walls and roof panels simply fill or clad the gaps between them. In its traditional form the members are joined wood to wood, with mortise and tenon joints locked by wooden pegs. The same logic, a legible frame that does the structural work, still shapes cafés, houses, pavilions and social housing today.

What is timber frame construction?

Wikipedia's article on timber framing groups it with post-and-beam construction as a traditional method of building with heavy timbers that are squared, carefully fitted and joined, with the joints secured by large wooden pegs. Diagonal braces stop the frame from racking, the sideways lean that a box of posts and beams would otherwise suffer under wind or uneven load.

Three neighbouring terms are worth separating. Half-timbering describes a frame left exposed on the outside, with the panels between the timbers filled with a non-structural infill such as wattle and daub, brick or stone. It is a way of finishing a timber frame, not a different structure. Light frame or "stick" construction, by contrast, builds walls from many small sections of dimensional lumber nailed together, so no single member is visible or decisive. And mass timber uses engineered panels and beams, such as cross-laminated timber, at a scale traditional framing never reached.

What unites the timber frame family is the idea that structure and enclosure are separate jobs. The frame stands first; walls, glazing and insulation follow and can change over the building's life. That separation explains why so many old frames have been repaired, refilled and reused for centuries, and why architects still choose the system when they want structure that people can read.

A short history of timber frame

The Roman architect Vitruvius, writing in the first century BC, placed the framed wall at the very start of architecture. Describing the first huts in Book II of his treatise, he wrote:

"At first they set up forked stakes connected by twigs and covered these walls with mud."

Vitruvius, The Ten Books on Architecture, Book II, trans. Morris Hicky Morgan (1914)

That is a frame with infill in its most basic form. According to Wikipedia's article on timber framing, the most ancient known half-timbered building is the House of opus craticum at Herculaneum, buried by the eruption of Vesuvius in 79 AD.

In Japan, carpenters developed post-and-beam temple construction to an extraordinary level. The Kondō, or main hall, of Hōryū-ji near Nara was rebuilt after a fire in 670 and is widely recognised as the world's oldest wooden building. In 1993 the temple became part of Japan's first UNESCO World Heritage Site.

In England, the cruck frame, a pair of curved timbers rising from the ground to meet at the ridge, was in use by the early thirteenth century. The guide Looking at Buildings notes that most surviving English timber-framed buildings are houses of the later Middle Ages onwards, and that close studding (vertical timbers set tightly together) and projecting jetties became ways of showing off in the fifteenth century.

In North America, barns and town halls were raised by whole communities under a master framer. The Timber Framers Guild explains that the method remained one of the main ways of building in the United States until the early 1900s, when mills producing smaller dimensional lumber made light frame construction the norm. A group of builders revived the craft in the 1970s, and it has continued alongside modern insulation and machinery ever since.

Key principles of timber frame design

The frame carries, the wall encloses

A timber frame wall is thin because its stability comes from the whole frame: bracing, cross walls and the roof working together. Infill can therefore be chosen for warmth, cost or character. Juri Troy Architects' Straw Flea House, featured in a uni.xyz journal, wraps a load-bearing timber frame in straw insulation from a nearby farm, and lets the frame double as floor-to-ceiling shelving.

Joints that do the work

Traditional frames are held together by their joints: pegged mortise and tenons, laps and scarfs cut so that timber bears on timber. Good joinery is designed for the direction of the load and for the movement of wood as it dries, which is why traditional frames can be taken apart, repaired and reassembled.

The bay as a unit of design

Posts set out a rhythm of bays, and the bay becomes the module for planning, extension and prefabrication. The architect Walter Segal built a whole self-build method on this idea, using timber frames calculated on modular dimensions so that standard boards could be used without waste. The writer Colin Ward summed up Segal's attitude:

"He insisted that his was an approach, not a system, and he made no claims for originality or patents."

Colin Ward, Walter Segal: Community Architect, Walter Segal Self Build Trust

Structure on show

Because the frame is the building's logic, timber frame design usually exposes it. In KOMINORU Design's 140 square metre house in Hyogo, the exposed timber frame sets up a rhythm that draws each room upward toward a clerestory slit along the ridge that brings in light and drives ventilation.

Lifted off the ground, paired with mass

Timber lasts when it is kept dry, so frames are traditionally raised on stone or masonry. Contemporary projects often go further and pair the frame with concrete or brick that handles moisture, stiffness or fire separation, letting each material do what it does best.

Timber frame on uni.xyz

The timber frame work on uni.xyz is unusually wide in scale, from a six square metre hillside shelter to housing for dozens of families. Many of the strongest examples are journals that study recent buildings closely; these are the ones we would start with.

The Hive by Ishan Dsa and Abhilash Menon was a winning entry in the Timberate competition. It is a social housing proposal for the Netherlands that tackles affordability through modular timber construction, with the modules arranged around two community courtyards.

safe house by Dominika Meres, an Editor's Choice entry in The SafeHouse competition, is a shelter for homeless students in Jackson, Mississippi, built around wood as its main material and designed to blend interior with exterior.

Horibe Associates' Cafe N+ in Takatsuki, Japan, is just 17 square metres. Completed in 2024 between a historic shrine and a new theatre, it is built from three moves: a board-formed concrete plinth, a light timber frame under a cantilevered cedar eave, and wire-mesh glazing.

The Live Oak Farm Pavilion by Austin Sandy Architects gives a certified organic farm in Petaluma, California, a 1,200 sq ft timber frame under one flat roof, with walls that slide, pivot or stay put. The journal's verdict is a good definition of timber frame restraint:

"The design succeeds by doing a few things precisely and then getting out of the way."

UNI Editorial, Austin Sandy Architects Builds an Open Timber Pavilion for Community Life on a Petaluma Organic Farm (uni.xyz journal)

PAVA architects' Nachan hotel in Chiang Khan, Thailand, builds a cluster of pavilions from solid timber salvaged from old houses, warehouses and rice mills, with a concrete core that hides the bathrooms and stiffens the frame.

Two journals show the frame as a tool for working with existing buildings. In Zhongshan, Modum Atelier keeps the brick firewalls and timber frame of a Qing dynasty qilou and adds a glass and timber box for a 77 m² café. Near Buenos Aires, DRM Arquitectura wraps an existing concrete building in a timber post-and-beam frame and a long sloping roof to create a drive-through ice cream shop.

At the scale of housing, Atelier Régis Roudil Architectes curls 46 social housing units around a courtyard near Toulouse, combining a timber frame structure with unfired earth brick and wood wool insulation. Cinema WAVE, the winning entry in Cinema Futurismo by 유진 양, 수진 김 and 상민 박, strips a cinema down to an open timber frame that park life can move through.

Challenges and future directions

Timber frames ask for care that concrete does not. Wood moves as it dries, so joints and finishes must allow for shrinkage. It must be detailed to shed water and stay ventilated, or it will decay. Fire has to be addressed through member size, protection and compartmentation, and large, straight-grained sections are not available everywhere. Skilled framers are also scarce: in North America the craft had to be deliberately revived by a group of builders in the 1970s.

The future points in three directions at once. The first is engineered timber, which extends the frame upward and outward. Nicholas Jeffway's Madison Square Gardens, an Editor's Choice entry in CityScraper 2020, imagines a mass timber megastructure holding a vertical farm, classrooms and gardens inside Manhattan's Madison Square Park.

The second is reuse: salvaged timber, as in the Nachan hotel, and existing frames kept and adapted rather than demolished. The third is the light, hands-on frame that small teams can raise themselves, the tradition of Walter Segal's self-builders and of barn raisings.

Timber frame for students and designers

Timber frame is an excellent thesis subject because the structure, the construction sequence and the architecture can be shown in the same drawing. Promising angles include a self-build housing system based on a repeatable bay, the adaptive reuse of an old frame, a public pavilion assembled from reclaimed timber, or a hybrid of timber and earth for a hot climate. Draw the joints, the order of assembly and how the building could be taken apart.

Briefs on uni.xyz competitions regularly reward this kind of clarity. For more background, explore timber architecture, reclaimed timber and Japanese architecture.

Frequently asked questions

What is the difference between timber frame and light frame construction?

A timber frame uses a small number of large posts and beams, joined to each other, as the structure. Light frame or stick construction uses many small pieces of dimensional lumber nailed together into structural walls. The Timber Framers Guild traces the shift from one to the other in the United States to the early 1900s, when mills began producing smaller lumber.

What is half-timbering?

Half-timbering is a timber frame left exposed on the outside of a building, with the panels between the timbers filled with infill such as wattle and daub, brick or stone. In England the look is often called "Tudor" or "black-and-white".

How long can a timber frame building last?

Well-detailed and maintained frames can last for centuries. The Kondō of Hōryū-ji in Japan, rebuilt after a fire in 670, is widely recognised as the oldest wooden building in the world, and the Timber Framers Guild notes that many historic timber-framed structures are still in use today.

Can timber frame be combined with concrete or steel?

Yes, and many recent projects do so. On uni.xyz, Cafe N+ sits on a concrete plinth, the Nachan hotel uses a concrete core to stiffen its frame, and Veneciana Escalada wraps a timber post-and-beam frame around an existing concrete building.

Where can I follow timber construction news?

The journals listed below this article are updated as uni.xyz publishes new timber frame buildings and student projects. The mass timber topic linked above covers engineered timber in more depth.

References and further reading

• Timber framing, Wikipedia
• Hōryū-ji, Wikipedia
• Vitruvius, The Ten Books on Architecture (trans. Morris Hicky Morgan), Project Gutenberg
• Timber Walls, Looking at Buildings (Buildings Books Trust)
• Historical Practices, Timber Framers Guild
• Walter Segal: Community Architect, by Colin Ward, Walter Segal Self Build Trust