So many variables come into play when choosing the best structure for a multi-storey building. What are the budget constraints? Are there environmental factors to consider? What type of building is being erected? The answers to these questions will inevitably point the contractor to one of the “big three” materials: wood, concrete, or steel.
Each one has its benefits and drawbacks, and if your design is truly optimized for your chosen structure, they can all be cost-effective. You might not realize it, but design can have a greater impact on the cost of a project than the materials themselves!
Read on to explore key differences between the three most popular construction materials, from fire resistance to environmental impact.
In Canada, the cost of steel typically falls between wood and concrete, and the associated return on investment (ROI) is generally quite high. According to a recent study by ArcelorMittal comparing six-storey concrete and steel structures, steel came in 9.6% cheaper than concrete with all factors considered and apple to apple comparison is made.
This low-maintenance material has a longer lifespan than wood, which makes for lasting structures that can be erected in any type of weather. Thanks to lightweight profile of steel components and high strength to weight ratio, foundations for steel buildings are considerably lighter than under concrete structures that can be up to 50% heavier than steel structures. Steel also has an advantage in the event of earthquakes. It offers the highest ductility of all materials and allows resistant building steel structures to bend considerably without breaking. In the event of a fire, steel will not combust, while wood carries a larger risk – in short, its durability is a major selling point!
Steel has recycled content of 93% and a recycling rate of 98%, which makes it the highest of any building framing material. Other products can only be recycled into lower quality products (down-cycled), while steel can be recycled over and over again and remade into new components without any loss of quality (multi-cycled). This makes steel the first and only true “cradle to cradle” building framing material.
Since you can prefabricate steel components, this material is particularly easy to install and requires much less manipulation on-site. Compared to wood and concrete, it provides superior sound insulation, and contrary to popular belief, it’s just as effective for climate control (since all structures need to respect the same energy efficiency standards).
Similarly to steel, concrete boasts high sound and fire ratings, and it is overall quite durable and low-maintenance. However, it cannot be cast in certain weather conditions, making for a shorter construction season: it is unable to set in the winter or in extreme heat. Additionally, while steel is 100% recyclable, concrete can only be reused as aggregate, and it creates lots of CO2 during production.
Given the limited regional availability and the lack of skilled labour required to install it, this material is typically the most expensive of the three – though prices do fluctuate quite a bit from coast to coast. The weight of concrete makes it susceptible to damage in the event of an earthquake, and it is also associated with more costly soil improvement when used on a subpar soil condition.
In our recent case study we compared the building schedule of our Hambro steel building system versus traditional concrete, for a four-story 155,000 square feet (14,400 square meter) senior care residence and we found that the steel structure took 10 weeks less to erect (14 weeks for steel versus 24 weeks for concrete). This translates into hundreds of thousands of dollars in savings if building revenues and reduced bank interest costs were taken into account due to earlier occupancy of the building.
Traditionally, wood is the lowest-cost material on the market, though it tends to be less durable than steel and concrete. Due to shrinkage, warping, and susceptibility to mold, wood requires more maintenance, and it is more vulnerable to pest infestations due to its organic nature.
In that same vein, construction of wood structures are highly susceptible to adverse weather conditions and must be erected in good weather conditions: if the percentage of moisture in the wood material is too high, the wood will experience too much shrinkage and you will be unable to close up the structure. If you are building in a predictable climate, this should not be an issue, but it can lead to delays and budget overages in less consistent climates.
Compared to steel, wood is often not prefabricated, meaning that most of the components need to be cut and assembled onsite. While labor for wood tends to be more available and less expensive, the additional input can still rack up a large bill. Arguably the largest drawback of wood is the combustion risk and fire protection: on-site, it is prone to fire due to the friction created by tools and the heaters used on the construction job sites.
When there is a fire in a steel or concrete building, the structure does not burn; only the finishes and contents inside the building. Following a fire, steel and concrete buildings can be rehabbed and reused again. The same is not true for combustible wood construction. That is why the All Risk insurance rates for wood buildings are double those for steel buildings. It is much less cost effective to bring the wood structures to the same level of basic code requirement for fire and sound protection.
Environmentally speaking, wood has the lowest carbon footprint, especially if it is harvested sustainably and associated with forest regrowth efforts. However, it is less recyclable than steel, and its availability can be limited if a harvest zone is experiencing a pest infestation or fires.
While some construction materials are fundamentally more available and affordable than others, you can make nearly any project cost-effective with the right design. It is all about working around your chosen material, understanding its strengths and weaknesses, and being ready to explore different options if they better suit your design. If you have not already, we recommend giving steel a fair chance – in many cases, it blends the best of all worlds, and it might just surprise you!
Want to see what your next project could look like if you used a steel structure? Our experts can help you adapt your design, define your budget, and build an optimized schedule that will have your structure delivered on-time with no overspending.
In an earlier blog, we discussed whether steel or concrete is the best building material for low-rise construction. We compared the pros and cons of each system in four categories: design, size, availability, and safety.
However, does a prefab steel building system or building with concrete cost less?
Is building with concrete or steel the best choice for our environment?
CONCRETE: Ordinarily, the price of concrete itself remains relatively stable. Moreover, concrete ingredients are inexpensive and readily available.
STEEL: The secret to the affordability of a steel building system is steel’s strength.
Steel boasts the highest strength-to-weight ratio of any building material. Therefore, steel creates a stronger building with far less material than concrete. Less material equals less material costs.
In addition, innovations in steel production now allow for the creation of one ton of steel in less than one man-hour, making it an extremely cost-efficient building material.
Using recycled materials also reduces steel’s material price. Domestic structural steel contains 77% to 90% recycled steel.
In fact, the steel industry’s efficient steel scrap collection system recaptures 98% of all discarded steel products for recycling.
CONCRETE: Labor-intensive reinforced concrete buildings require a skilled contractor and experienced laborers for satisfactory results.
Building with concrete requires waiting for the concrete forms to cure thoroughly. That also lengthens construction time. The longer the construction time, the higher the construction costs.
STEEL: The prefabrication of the RHINO metal building system drastically cuts construction time, saving money on labor. The straightforward nature of the framing erection and steel construction requires fewer, less skilled workers, further cutting construction costs.
Faster construction reaps lower interim financing and builder’s risk insurance costs, too.
On small to mid-sized building projects, do-it-yourselfers often save money by erecting the framing themselves with a few friends. Yet, no do-it-yourselfer would dare take on reinforced concrete construction.
When choosing a construction material, too many building owners fail to consider the cost of maintaining and operating the structure. Which building system offers the lowest long-term costs?
CONCRETE: The sheer mass of cast-in-place concrete reduces temperature swings and drafts, saving money on heating and cooling. However, concrete buildings do require constant maintenance and repair.
STEEL: Steel buildings hold their value for decade after decade with virtually no expensive maintenance.
Steel’s thermal transfer properties do present an energy-efficiency challenge. However, a first-class insulation system like RHINO’s Pro-Value Package easily overcomes that problem.
In fact, RHINO’s Pro-Value Insulation System reduces heating and cooling costs by about 50%!
Construction and demolition waste is a huge environmental problem.
The EPA estimates construction and demolition waste in the U.S. at 600 million tons per year. That is more than double the amount of municipal solid waste generated annually.
CONCRETE: At the end of its usefulness, the concrete in a building can be recycled— but it is no longer fit for construction use.
Recycling concrete is also NOT economical.
Consequently, only about 50% of demolition concrete is recycled. The other 50% ends up dumped into our overflowing landfills. That creates a real environmental problem.
Concrete is made with cement— a major source of carbon dioxide gas emissions.
On the other hand, light-colored concrete does reflect heat, which helps to reduce the effects of urban heat islands.
Fortunately, the steel rebar used in reinforced concrete buildings is 100% recyclable.
STEEL: As the most recycled material on the planet, steel reigns supreme as the greenest of all materials.
In fact, the U.S. Green Building Council proclaims steel framing as “the logical and responsible choice for Green Building.” Here’s why:
Why pay someone to haul away the concrete of your demolished building? Scrap dealers will actually pay you for the deconstructed steel framing!
Unfortunately, steel, like cement, also produces some carbon dioxide emissions. However, innovations in steel production in recent decades have reduced greenhouse emissions by 37%.
Ongoing research and development continues searching for ways to further reduce both emissions and energy used in steel production.
According to the American Iron and Steel Institute, “Today, the American steel industry operates with the lowest energy consumption per ton of steel produced in the world.”
Using reflective steel panels on metal buildings helps diminish urban heat island effects in cities.
Ultimately, only you can decide whether reinforced concrete or steel works best for your specific project.
Compare the design, the end use, and the building codes for your location, as well as the short-term and long-term costs.
One alternative you might consider is a hybrid building that employs both steel and concrete construction. For example, tilt-up concrete works very well in combination with RHINO’s pre-engineered steel framing.
Speak to a RHINO metal building specialist today for more information.
Find out more about hybrid structures using both prefab steel buildings and tilt-up concrete. Discuss your specific building requirements. Ask for a free, no obligation quote.
You can trust our experts and their years of steel building experience. Call RHINO today at 940.383.9566.
(Updated 6-30-2021. Originally published 4-6-2018.)