Steel vs. Timber Frame: Which Should You Choose?

Giovanni Valle is a licensed architect and LEED-accredited professional and is certified by the National Council of Architectural Registration Boards (NCARB). He is the author and managing editor of various digital publications, including BuilderSpace, Your Own Architect, and Interiors Place.

Building a home or structure requires that you make several decisions. Although personal preference is a crucial factor when choosing your frame, you need to consider which one is better for your specific building project.

When choosing which is better between steel and timber frames, consider the cost, sustainability, flexibility, and longevity during construction. Consider steel frames if you want a frame that is not receptive to damages due to termite invasion, and pick timber if you want a pocket-friendly frame.

As you continue reading this article, you’ll get to learn more about these two options through a detailed outline of how they work, as well as their pros and cons.

Steel Frames: A Basic Overview

Structural steel framing refers to building systems where the horizontal and vertical structural elements are formed by an arrangement of steel columns and beams. These beams and columns are assembled to provide internal fixtures, roofs, finishings, and floors with support. Steel frames are cost-effective, durable, sustainable, and reliable options for high rise, warehouse, residential, industrial, and temporary buildings.

The spacing of columns is usually 25ft to 45ft (7.6m to 13.7m) on center. However, these variations can be higher or lower depending on specific architectural requirements. Any of these requirements can be met due to the availability of various ranges of sizes and shapes. Mild steel is the most common when it comes to construction because of its immense strength.

Structural steel follows standards of fabrication, design, and erection established by the American Institute of Steel Construction and Canadian Standards Association in the United States and Canada, respectively. There are many types of steel construction. They include conventional, bolted, and light gauge steel fabrication.

Pros of Steel Frames

Steel has become a common material for the construction of various kinds of buildings due to its advantages. They are:

High Strength

Steel components, when compared to concrete or wood, are stronger and lighter. Steel fabrication is 30 to 50 percent lighter than an equivalent of wood. Fewer steel frames are necessary for providing a similar amount of support given by wood. The reason is that steel is dense, and for the same length as wood, it will convey a heavier load.

Consequently, there is a decrease in the material needed hence reduced shipping costs, labor, and results in a simplified design of the structural supports and foundations.

Versatility

Steel framing is flexible. It can easily be fabricated into several shapes and still maintain its strength. Designers and architects take advantage of this ability to come up with innovative and creative designs that are structurally sound and aesthetically pleasing. They also allow for easy future-proofing in terms of modification and making structural additions like the expansion of a building or renovations.

Its versatility allows the construction of high-rise buildings, bridges, and large-spans like aircraft hangars and indoor arenas.

Longevity

Assuming that steel, concrete, and wood are well maintained, steel will last longer. It does not crack, creep, or split with age. Steel is not prone to pest and insect attacks because it lacks porosity. Therefore, mildew and mold cannot grow on it. Structural steel also possesses properties of moisture and weather resistance, depending on the carbon contents.

Steel can be made to be more immune to weather effects by enhancing resistance to rust through additional powder treatments and hot zinc coating. However, contact with water should be avoided to increase its longevity. Steel frames are highly resistant to fire, thus reducing the risk of fire and one spreading if it occurs. A special flame-retardant coating enhances this property.

Safety

Steel frames have a tensile strength that allows them to perform effectively under several circumstances of natural phenomena like snow loads, seismic activity, and hurricanes. As the building goes higher, these natural phenomena become more challenging.

Steel provides safety against human-made emergencies such as impact and fire explosions because it is non-combustible. However, when exposed to extreme temperatures, its strength is compromised.

Sustainability

Computers can be used to model steel before fabrication, therefore, reducing the amount of scrap left out. Also, during other project processes, the scrap is reusable because when it is melted, steel doesn’t lose intrinsic properties like strength. The remaining can be used for future projects without compromising on quality.

Faster Construction and Production

Production of steel products such as floor plates and standardized bolts is fast during manufacture because of computer use. Regulatory policies and standardization have made it easier and dependable to erect steel frame components. Before the steel frames are delivered to the construction site, they are pre-fabricated to suit particular specifications.

When they are sent to the construction site, only minimal labor and time is required to assemble the parts immediately by welding or bolting the pieces together. It is unnecessary to wait for sections to cure or for temporary formwork that ends up being dismantled after assembly.

Space Maximization

Bays inside steel frames are spaced to create wider bays due to their strength. Wider space makes it possible for flexible flooring designs that make the most of the obtainable space.

Maximization of floor space in housing is also possible because there is a reduction in the need for timber posts to bear the load. During an inspection, this aspect makes it easier and accessible to maintain the steel frames.

Cost-Effectiveness

Fabrication of steel frames off-site, with the help of computers during the manufacturing process, reduces the amount of labor force and time required during construction. Therefore, the cost of labor is reduced while chances of accidents and injuries occurring reduce due to a fewer number of workers.

A reduction in the time taken for construction also means there are fewer interest payments for overtime, and the building, if it is for rental, can start earning back money faster. Steel, being durable, reduces the cost of maintenance when it comes to replacements and repairs.

Homeowners also gain access to cheap insurance premiums because steel is durable and can withstand pests, natural calamities, and decay.

Cons of Steel Frames

Although steel frames have incredible advantages, there are a few disadvantages to look out for and consider. However, they do not outweigh the benefits. They are:

Thermal Conductivity

Steel efficiently conducts heat. Therefore, it is necessary to install materials that enable the building’s insulation to counteract the steel’s thermal conductivity. Steel walls reduce the insulation value by almost half when heat transfers through them, hence compromising a building’s energy retention.

On-Site Reduced Flexibility

Unlike wooden structures that are adjustable during construction, steel frames undergo fabrication before delivery to the site. Although this is considered to be one of its biggest advantages, any inaccurate measurements will result in delays. The construction has to be put on hold until the inaccurate component is brought back from the workshop after rectification.

Support Structures

Steel frames require insulation, supplementary wood, sheathing, and drywall because they rarely work on their own. These components, together with steel, work to bring up the desired building. During construction, the inclusion of these components may increase the time taken. However, they save on time that could be used to make adjustments.

Timber Frames: A Basic Overview

Timber frame construction has been taking place all over the globe for millennia. It was initially used in the United Kingdom and throughout northern Europe but has since been adopted in the United States and Canada as well. The use of timber frames has slowly but surely become more modernized, with new styles, designs, and construction methods being developed.

Growth in timber use has also seen various countries adopting policies such as planting trees once others are cut. Also, there are specifications and guidelines to be followed during construction to enhance the occupants’ safety. Although other materials are coming up in construction, for example, steel, timber remains among the top used materials.

Timber frames are wooden load-bearing structures that are held together using tenon joinery and mortise. Instead of using steel connections or bolts as in beam and post buildings, the ends of timber frames are cut so that they can fit together. This is done by fast holding the joinery with pegs made out of wood.

Over time, methods of construction using timber frames have evolved, making their use more advantageous not only to the owners but also to the contractors. Timber frame construction is no longer limited to the use of hand tools by the builders. There is the use of both hand and power tools such as chain saws, chain mortiser, and chisels.

Timber frames can now be pre-fabricated partly in the factory according to given specifications. Inner and external stud walls, roof trusses, and floor joists are manufactured-offsite to form a complete super-structure that then transfers the horizontal and vertical masses to the foundations. This makes work easier, faster, and cost-efficient.

Pros of Timber Frames

The use of timber in construction will remain a staple in the industry. Timber has been used for thousands of years for many reasons. These are:

Versatility and Lack of Limitations on Design

The versatility of timber allows it to be used in various ways. It’s technical and physical properties allow for endless possibilities when it comes to the size and design of a building. As opposed to platform designs, timber frames rest their weight outside the home, hence creating an open concept where walls may seem unnecessary.

Timber frames are easy to install by the use of simple equipment due to its light nature. Also, different kinds of timber provide different textures, colors, and practical qualities. Timber frames eliminate the dilemma of having load-bearing walls that limit creativity and leaving open spaces. It also makes it possible to have more windows that allow in natural light.

Insulation Properties and Energy Efficiency

Timber helps to reduce energy consumption in various ways. These houses outperform concrete and steel houses significantly when it comes to minimizing energy use. Timber thermally insulates the building naturally, and when used on doors, floors, and windows, they help reduce energy needs.

Energy-efficient buildings retain cool air during the summer and retain warm air during winter; timber frames have insulated panels that make this possible. The panels are air pockets that limit their capability to conduct heat. Insulated panels, also known as SIPs, surround the timber and are efficient in reducing allergen effects.

Natural, Eco-Friendly, and Sustainable

Timber frame is a natural building material; it has no toxins. Therefore, it’s safe to touch or handle and doesn’t emit chemical vapor. The fact that timber reduces the amount of energy required to be used in a home makes it environmentally-friendly and sustainable. Also, timber is a renewable source of energy, in the sense that it can be re-grown.

Many countries have implemented policies where one has to plant trees to replace those that are felled. When more trees are planted, timber continues to be available. In various countries, timber is milled locally, reducing the energy that would otherwise be used to transport it over long distances and promoting local economies.

During production, it takes minimal energy to convert the wood into timber frames for construction. Timber frames act as a store for carbon that would otherwise contribute to the greenhouse effect, making it eco-friendly.

Easy Maintenance and Durability

Some structures made from timber frames last for years because of its durability. These structures also provide safety against earthquakes that are at a degree of 7.5 on the Richter scale. To some extent, when timber is erected properly, it can offer a certain level of fire-resistance because the fire would take time to penetrate through all thick layers.

Timber is easy to maintain and carry out repairs since you can add different paint or flip your house using the same beams.

Time-Saving and Cost-Effective

It takes less time to build using timber frames in comparison to concrete. They can be pre-cut partly, modified, and constructed. Also, construction starts quickly because there is less debris to clear. Constructing a building using timber only requires basic technical and specialized skills that are inexpensive, thus saving on costs. Since building takes a short period, it also saves on costs of labor and time.

Prior fabrication also eliminates errors, and this saves on extra costs. The insulation properties of timber also save on heating costs.

Cons of Timber Frames

Timber is an excellent option for building, but some of the disadvantages you should be aware of are:

Condensation

Condensation occurs on the surface of the timber or internally between the building’s envelope layers. It results from warm air leaving the interior, diffusing into the cold exterior, and attaining its dew point on the building material. During construction, timber frame designers must include a barrier that prevents vapor from passing through the insulation and inner wall.

Pest Infestation and Rotting

Because of being a natural product, a timber frame is prone to shrinkage or swelling because of its permeability to water. If not treated with water-resistant components, its exposure to water can result in rotting and growth of mold or mildew, hence lowering its quality. In order to prevent rotting or keep it at a minimum, timber frame buildings should have adequate heating.

Heating lowers the moisture content, therefore reducing the risk of pest infestation by woodworm and beetles. Proper construction and maintenance also aid in eliminating conditions suitable for infestation.

Fire Risks

In comparison to steel and concrete frame, timber frame is at a higher risk of failing when subjected to high temperatures caused by fire; the risk increases when timber frames are poorly erected.

However, if it burns, the char on the outer parts becomes charcoal that insulates against excessive heat and burning. You can use fire retardants to slow down the spread of fire on its surface and also reduce smoke production.

Poor Soundproofing

Sound insulation is not among the strong suits of timber frames. Timber frame, being a lightweight material, people find older homes to be squeaky. When there is a difference in temperatures, timber frames shrink or expand, producing a squeaky sound from their joints. However, soundproof components and insulation materials can be installed to counteract this issue.

Here is a video on how to soundproof a timber floor:

Which Should You Choose?

Essentially, the kind of frame you choose for your construction will depend on your preference, environmental conditions, and the type of building. If you’re erecting a high-rise building, use steel because of its strength. If you’re building a low-rise, residential home and looking to save on energy costs, timber frames will be a better option.

However, decide after carefully considering other factors such as natural calamities, weather, costs, and future needs. Also, with steel construction, you can use timber for support; that is still an option you could explore.

Conclusion

Steel and timber frames have their pros and cons, but they are both popular building materials. In addition to preference, consider if these will work for you and the kind of building you want.

Steel frames are versatile, strong, sustainable, cost-effective, and allows for speedy construction. However, it has cons like thermal conductivity and has reduced flexibility while on-site.

Timber frames are advantageous because they provide insulation, are natural and eco-friendly, versatile, sustainable, energy-efficient, durable, and save on costs. However, they pose a risk when exposed to fire and water—exposure to water or moisture results in rotting and infestation.