A Comprehensive Guide to Timber Frame Constructions
In this detailed guide, we aim to cover the viability, materials used, methods involved, and benefits of timber frame construction to help you decide if it can align with your dream of constructing your home.
The UK government has targeted to increase the production of homegrown timber to reach its commitment of delivering 1.5 million homes. The aim is to not just deliver to solve the housing crisis, but to do it with sustainable and efficient methods. According to the NHBC data, the UK timber frame construction market is expected to reach a market share of 27% by this year. Interestingly, the UK government too is speeding up initiatives to achieve its target of building 1.5 million homes, and a big part of this initiative is to increase timber production. It’s all looking like a great story coming together for a sustainable & hopeful future. With a lot going on, including ongoing research on new methods of construction, diversification of usage, and types of applications, one can safely say that in the present day, timber frame constructions have spiced up the building & construction sector like no other.
Timber frame construction is a building method that uses timber frame as the means of structural support. A timber frame construction is usually characterised by creating timber joists, beams, and columns to create the structural or skeletal framework.
In the present day, timber frame constructions are becoming popular for their energy efficiency, speed of construction, and lower labour costs. Their popularity is much owed to their nature of being extremely eco-friendly as they are great at absorbing carbon properties and are hence considered as one of the most efficient & sustainable choices when it comes to building & construction.
How are Timber Frame Houses Constructed?
Timber frame houses UK are built by means of prefabricated timber frames built at an off-site facility. The frame acts as the main structural support with walls, joists, floors, and roofs, being engineered and designed as an integrated framework.
Below is a detailed breakdown of how they are built –
1. Prefabrication
Most timber frame structures, including the walls, floors, roofs, and joists are built at an off-site facility in a controlled environment. The process leverages precision engineering which allows for precise cutting, joining, and assembly of timber frame panels ensuring accuracy and quality.
Walls and ceiling elements are built as prefabricated insulated panels ready to be transported on-site for erection. Cladding of timber frame structure (elaborated further in another section) is done with materials like bricks, fiber-cement panels, wood, or suitable tiles. The cladding is usually done both for decorative and insulative purposes (mostly to insulate the inner space from changing weather conditions).
2. Design
Designs for walls, roofs, and floor panels are created by means of CAD software to ensure accuracy in the dimensions of the timber frame components. Structural analysis is carried out on a simulation software to assess loads acting on the timber frame to ensure strength and rigidity under various conditions. Material selection too is mostly carried out by means of software that reflects different results for different materials and other varying components.
3. On-site Assembly
Once the off-site work is done, the prefabricated panels are then shifted on-site by means of a haulage. At the on-site facility, the timber frame superstructure is erected on the foundation (typically a concrete slab or a timber frame base) followed by installation of the floor joists. The panels are then erected and joined to form an assembly; this is usually done with pre-installed screws and bolts.
4. External Cladding
Once the erection is completed, cladding of the outer structure is carried out. Materials used are typically wood, fiber-cement boards, brick slips, reclaimed bricks, stones, and sometimes composites.
During cladding, considerations for ventilation to allow the escape of moisture are given. To protect the timber frame from harsh rains, and windy conditions, a breather membrane is used which resists the penetration of moisture.
Besides protective purposes, cladding is also done to enhance the aesthetic appeal of the building.
5. Internal Works
Once cladding is completed, the frame is then taken for internal finishes such as adding electrical & plumbing connections, and HVAC systems. Stud walls are created to create division of spaces internally. They are usually made of metal or timber. While spacing the studs, gaps often remain which are filled with an insulating material to achieve good thermal performance and acoustic benefits.
What are the Materials Used in Timber Frame Construction?
A timber frame construction is subjected to many static and dynamic loads. To ensure the structural strength of the framework, it is crucial to choose materials that are robust and that last longer.
Below is a breakdown of the materials used –
1. Structural Timber
Structural timbers are primarily load-bearing elements and form the frame of the building including the walls, roofs, and floors. The components of structural timber include vertical studs, horizontal rails, and beams that support the floor.
- Commonly used hardwoods – Pine, Douglas fir, Spruce
- Commonly used softwoods – Oak, Ash, Maple
- Glulam beams or Glue Laminated Timber for frames that involve large spans.
- Cross Laminated Timber (CLT) for walls, floors (for higher strength & durability).
- Laminated Veneer Lumber (LVL) are used as beams, rafters, studs, and purlins for floor joists, headers, and rim-boards.
Materials used for cladding have a lot to do with aesthetics, maintenance, and resistance to external weather conditions; so are the choices of materials.
- Timber cladding materials include softwoods like red cedar, pine, and larch. They offer good durability and resistance to decaying (especially red cedar).
Timber cladding requires regular maintenance in the form of painting and similar options to avoid discoloration and warping. - Metal cladding involves materials such as steel which is often a durable material or aluminium which is lightweight and anti-corrosive. Zinc can also be used for durability and sustainability.
- Composite cladding usually is a combination of different materials like wood, metal, and sometimes plastic. They can be more effective when the combination hits the right chord resulting in durability and low maintenance.
Fiber-cement is also used as a composite cladding material and is usually made of cellulose, cement, and other composites. They offer high durability, are moisture resistant, and require less maintenance. - Other cladding options like brick cladding and stone cladding are high on durability but can be expensive in terms of cost and maintenance.
Tile cladding and uPVC cladding though are cost-effective and low-maintenance options, they may not offer the strength required.
Sheathing is the process of adding a structural layer to the external frame to create a strong base for cladding and to insulate it from weather extremities.
Materials used for sheathing –
- Oriented Strand Board (OSB)
- Plywood
- Cement Board
- To improve the insulative characteristics and thermal performance of the structure, insulation materials such as cellulose, and mineral wool are usually used.
- To increase the structural strength of the superstructure, strip foundations are generally used that offer stability and sturdiness.
The cost of timber frame houses UK depends on various factors such as the design complexity, type of the timber frame structure, layout of the house, number of windows, and the on-site location.
The cost to build a timber frame house in the UK can range from £1,800 to £2,500 per sq metre.
The average total cost to build timber frame houses UK are as follows –
- A 2-bedroom timber frame house – £2,00,000
- 3-bedroom timber frame house – £2,50,000
If you are self-building the costs are usually less and range from £220 to £280 per sq metre. For a demanding project such as the timber frame construction, it is always advised to seek professional help who are experts in the field.
At Extension Architecture, we have the skill and expertise to take up your timber frame construction project; whether you are looking for a newbuild or a timber frame extension.
Traditional vs Modern Timber Frame Construction
Choosing the type of timber frame construction plays a key role in the overall outcome of the project. So, if you are deciding on the choice, the details below may help you –
- Traditional timber frame construction involves the use of solid timber beams that are joined using traditional joinery techniques.
Modern timber frame construction uses engineered wood as prefabricated panels and is joined using modern connectors. - Traditional timber frame construction often is done on-site and requires highly skilled engineering and craftsmanship.
Modern timber frame construction is usually done off-site and involves precision engineering and other advanced techniques that help in faster assembly. - Traditional timber frame constructions though are expensive, offer high durability and structural strength.
Modern timber frame constructions besides being less expensive and can last for generations and offer great value upon investment. - Traditional methods are characterised by exposed beams and create a unique visual appeal.
Modern methods can be adapted to diverse aesthetic considerations and offer a warm and natural appeal. - Traditional methods though focus on energy efficiency and sustainability may not offer the desired output in comparison to modern methods.
Modern methods offer excellent thermal performance and minimise heat loss and wastage.
Both traditional and modern methods are quite effective and efficient when it comes to durability, strength, and aesthetic appeal. The only differentiators are the cost and the method of manufacturing. If you are in a conundrum about which of these methods would best suit you, consult our experts at Extension Architecture.
Open Panel and Closed Panel Systems
Choosing the type of frame is a crucial decision as the choice of frame has many factors surrounding it.
Open panel timber frames though offer more flexibility in terms of design, they are usually bereft of sheathing and insulating elements. External cladding can be considered for enhancing the aesthetic appeal and to secure the building from external conditions.
Closed panel timber frames on the other hand are pre-fitted with insulation materials and sheathing and hence are highly energy efficient besides taking faster time to build.
Important Considerations for Timber Frame Construction
Building a timber frame house is not just about materials, process, and execution, there are other important factors you should be aware of when planning a timber frame construction –
1. Structural
Make sure that the timber frame has the required strength to sustain and support all types of loads including seismic, wind, and other external & internal loads.
2. Area/Scale of the Building
Most timber frame constructions are suitable for a 2-storey or a 3-storey construction, but not beyond that. If you are planning for a 4-storey or a 5-storey construction or beyond the height of 20m, the construction may be vulnerable to stability issues and sometimes even collapse.
3. Climate
When building, be aware of the building’s orientation so that your living space can take in maximum natural light and gain from solar heating.
Benefits of Timber Frame Construction
- Sustainability
Timber frame structures require less energy than other means such as concrete or steel and hence contribute to high energy efficiency and reduced carbon emissions. - Time Taken to Build
As timber frames are manufactured off-site in a controlled and mechanised environment, they can be quickly erected on-site saving significant time on other internal and external jobs. - Aesthetic Style
Timber frames can be adapted to suit diverse architectural styles. From the barn-like rustic look with exposed beams to fit into the idea of a modern living space. With the use of precision engineering and modern methods, these panels can be designed to any style. - Thermal Properties
Timber is a great insulator and is a slow absorber of heat. Besides that, with all the sheathing and air-tight construction, the level of thermal performance only increases and thus offers excellent thermal properties.
Besides the above benefits, timber frame constructions are excellent in insulating noise and ensure maintenance of optimal acoustic levels inside the building. They are also less invasive to the environment because of their structural durability which can last for decades and even generations.
Timber frame constructions generally require planning permission for new builds and as well as extensions too. Factors such as location, appearance, and size of the construction may play key roles. However, it is mandatory that all timber frame houses require adherence to building regulations.
Conclusion
In timber frame construction, there is a rapidly growing and sustainable construction option on the cards. With all the benefits and cost efficiency they offer, you have an excellent prospect in hand to make your living sustainable and comfortable, yet that aligns with modern needs.
If you are planning for a timber frame house, you have the best experts to guide you at Extension Architecture. Our RIBA chartered architects are proficient and industrious in all types of construction projects including timber frame buildings.
With a keen eye for energy efficiency, our architects ensure every project contributes to the environment and delivers on longevity and quality while also weighing lighter on your budget.
