Structural Steel Beam vs. Wood Beam: Which Is Right for You?

If you’re building a new house, adding on to your house, or doing major renovations, your construction project will need structural beams to support the weight of the house. Steel and wood are the two most common materials for structural beams, and each has its own pros and cons. Learn the differences between structural steel beams and wood beams so you can choose the right material for your building project.

Structural Steel Beam vs. Wood Beam: Key Differences

Whether you need to replace a main house support beam, install a basement support beam, or build a new house, structural beams are a fundamental part of making your house structurally sound. Structural steel beams are more durable and less prone to damage than wood beams, but they cost more and are much heavier to work with. Wood beams are more cost-effective and easier to install but are prone to rot and insect damage.

What Is a Structural Steel Beam?

Structural steel beams are a popular choice for building materials due to their strength and durability. These beams can support heavier weight than wood and require fewer vertical supports, so they’re often used in large, open spaces to avoid interruption by columns. They can also be used for increased strength to support extended rooflines and exterior features like balconies. 

The added strength does come at a price, though. In addition to costing more in materials, the cost to install steel beams is higher than wood because steel beams are much heavier and may require special equipment for installation. They may also take longer to fabricate and ship to the job site.

Best for: Homes with large open interior spaces, homes in areas prone to moisture and termite damage

Pros of Structural Steel Beams

When it comes to durability, steel beams have a much longer life span than their wood counterparts. Steel isn’t prone to rot, swelling, corrosion, or termite damage, and because steel can handle heavier weight, it’s less likely to bow, bend, or break. The higher weight-bearing strength also means steel beams can effectively support taller and larger buildings with fewer vertical supports. 

Cons of Structural Steel Beams

While steel beams can support much more weight than wood beams, they’re also much heavier. The added weight makes them more difficult to install, and they may require special equipment and handling during construction. Steel beams also take longer to obtain since they have to be fabricated off-site and shipped to the job site.

What Is a Structural Wood Beam?

Wood beams are widely used in residential construction and have been since long before steel beams became available. Wood is a fairly plentiful resource and an extremely versatile material that can easily be cut to size for various uses. Wood beams can be solid timber or made from composite lumber glued together, known as LVL beams. Both are less expensive than steel, and timber and LVL are similar in price. 

Wood beams are budget-friendly, easy to obtain, and easy to work with, but they’re prone to warping, shrinking, moisture, and termite damage, and they don’t last as long as steel.

Best for: Budget-conscious homeowners, building projects on a tight schedule

Pros of Structural Wood Beams

Wood beams are so common in houses because they’re affordable and readily available. They’re also a good choice if construction time is limited since they’re easy to obtain, can be cut to specifications right at the job site, and don’t require additional specialized equipment to install. 

Cons of Structural Wood Beams

While wood is a more budget-friendly material than steel, it also doesn’t last as long. Wood is prone to termite damage, shrinking, swelling, and rot, and wood beams need to be replaced more often than steel ones. Wood also has less weight-bearing strength than steel, so more beams and vertical supports are needed to support the same amount of weight.

Structural Steel Beam vs. Wood Beam

When it’s time to decide which material to choose for your construction project, consider the following factors so you can make the right choice. A local structural engineer can also help you assess the right material for your needs—a structural engineer can cost between $200 and $1,500 to hire, depending on the job.

Cost: Wood Beams

The up-front cost for wood beams is significantly lower than steel, so you’ll pay less in material costs when building. Depending on how long you own your home, though, wood may end up costing more over time if you need to replace or repair damaged beams. 

Ease of Replacement: Wood Beams

If you have a damaged beam that needs to be replaced, it’s easier to replace a wood beam than a steel one. Replacing steel beams will require additional equipment due to the material’s weight.

Ease of Installation: Wood Beams

When it comes to installing beams, wood is easier to work with and carries a lower beam installation cost than steel. Wood beams can be obtained and installed faster than steel and don’t need specialized equipment to handle the additional weight.

Durability: Steel Beams

Since steel beams aren’t prone to rot, moisture damage, or termite infestation, they’re much more durable than wood beams. As long as the steel is galvanized or treated, it will resist rust and stay strong for decades longer than wood.

Strength: Steel Beams

Steel beams have a much higher weight-bearing capacity than wood, so they are better for supporting larger or taller houses. Steel’s strength also means you can use fewer beams and columns to support an area than you would need if you used wood. 

Scale: Steel Beams

Because of steel’s ability to support more weight, it’s ideal for houses built on a larger scale, particularly those that include large open spaces you want to remain uninterrupted by columns. Steel is often used in larger-scale commercial construction. The qualities that make it the right choice for those buildings can be used to your benefit in larger residential construction.