Engineered Floor Joists Vs. 2×10: Which Should I Use?

When building or renovating a home, the support joists are a critical part of the process. It can be challenging for some owner-builders to choose between engineered floor joists and 2x10s, which are both great options. However, how do you know which one you should use? Is one better than the other?

Engineered floor joists are stronger than 2 x 10 joists and can cover a larger distance. Wooden 2 x 10 joists cost an average of $13 per square foot, and engineered floor joists cost $2.50 per square foot on average. It is easier to install engineered floor joists because wooden 2 x 10 joists are 40% heavier.

Many homeowners debate which is better, engineered floor joists or standard 2 x 10’s. They each have their own unique characteristics, and that is why both types of joists are so widely used. Let’s dig into the difference between engineered floor joists and 2 x 10’s. This will help you to understand when to use which product.

An engineered floor joist is a joist made up of several types of wood layered in multiple directions. Engineered floor joists are made up of top and bottom flanges and wood “webbing” connecting the two. Often times, builders will choose to use engineered floor joists for framing roofs and floors. Engineered floor joists appeal to many homeowners because of the low cost. Typically, engineered joists cost between $2 and $3 per square foot.

It is no coincidence that since engineered wooden joists have come into play, newer homes have more square footage on average. They can be adjusted on-site without having an engineer sign off on it, which makes engineered floor joists easy to install.

More than anything, engineered floor joists are the choice of homeowners and builders because they are strong, supportive, and straightforward. Even though they are lighter than 2x10s, engineered joists stronger and more solid. Besides that, engineered floor joists give you more of a surface area to hammer in nails making the job that much easier. You don’t have to worry about how engineered floor joists will impact electrical wiring because they provide plenty of space for it.

With standard wooden 2 x 10 floor joists, you can spend upward of $9 up to $17 per square foot, depending on where you buy from. Classic 2 x 10’s are adjustable on site like engineered floor joists, but generally, they are less maneuverable.

2 x 10’s are quite supportive, mostly because they are heavier than engineered floor joists. With that said, because 2 x 10’s lack the webbing and two flanges of engineered joists, they offer less support. Even though engineered floor joists seem to be becoming the standard recently, 2x10s are still often used.

Speak to your contractor, engineer, or team involved in your build or renovation. There are some contractors and builders that strictly adhere to engineered floor joists and vice versa. If your home has a lot of square footage, engineered floor joists may be the way to go. That is because of the low cost of material per square foot.

With that said, some builders and renovators are not comfortable using engineered floor joists because they are unfamiliar with it. As mentioned earlier, engineered floor joists have really only been on the rise for the past 15 years.

If the cost of materials per square foot does not matter as much, then going with classic 2x10s should be fine. Many contractors may push you in the direction of engineered floor joists, however. Not just because of the low cost of materials, but because of the easy installation.

Engineered floor joists are 60% lighter than standard 2x10s, and the flanges create a natural grip. Whether you are installing the engineered joists yourself or have a crew working on it for you, the ease of use makes the project go by quicker. Notably, engineered floor joists have an “I” cross-section, which accounts for how light they are without losing stability.

Both engineered floor joists and standard wooden 2x10s are considered safe but, of course, have their own risks. For example, engineered floor joists pose structural threats in the event of a fire that standard 2 x 10’s do not pose.

The added fire danger to engineered joists is because of the “I” cross-section. In the event of a fire, the webbing connecting the flanges into an “I” could catch fire and lead to a collapse. This creates more danger for firefighters entering a home to extinguish a fire in the event of one.

Of course, standard wooden 2x10s are flammable as well. The critical difference is that because 2x10s do not have an “I” cross-section, it poses less of an immediate structural damage than engineered joists. With that said, anything made of wood is flammable no matter what.

Whether you have engineered floor joists or 2x10s, overextending them can cause a danger. Overextending is essentially installing joists that are longer than they need to be. Doing so can lead to several significant problems, such as:

That varies from person to person, but most builders, carpenters, and homeowners find engineered joists easier to install than 2 x 10’s. That is mostly because there doesn’t need to be as many “hands-on deck” with engineered joists as 2 x 10’s. A single worker could easily carry one engineered joist on their own with no trouble. That not only makes it easier on the people installing them, but it saves time, which ultimately saves money.

As far as making adjustments, both 2 x 10’s and engineered joists can be trimmed on the spot easily. That is important because you don’t want overextended joists, or even worse, joists that fall short. Many carpenters and builders are so experienced with 2 x 10’s because they were the standard for so long that they can quickly install them. 2 x 10’s are not as easy to carry because there are no flanges to grip, and they are 40% heavier than engineered joists.

The wider surface area that engineered floor joists have makes it incredibly easier to hammer nails into. 2 x 10’s are not necessarily hard to hammer nails into, but the surface area is smaller, thus less forgiving when compared to engineered floor joists. Ultimately, neither one is difficult to install, but engineered floor joists are slightly easier to install than 2 x 10’s.

Both 2 x 10 timber joists and engineered floor joists are sufficient, and each has its own benefits. Engineered floor joists tend to be easier to install due to the flanges and how light they are. Timber 2 x 10 joists are easy to install as well but are 40% heavier than engineered floor joists. Engineered joists are cheaper, lighter, and easier to install than 2 x 10’s.

Whether you choose 2 x 10’s or engineered floor joists, be sure not to overextend your joists or cut them too short. This will defeat the purpose for which they’re used. Additionally, it can be detrimental to your overall structure. If you’re nervous about cutting your own floor joists, that’s okay! Contact a friend who can teach you how to do this, or you can hire a professional to cut them for you and take notes as you observe. In the DIY world, we all have to start somewhere.