Home-How » 2×6 Vs. 5/4 Decking: What’s the Difference?

2×6 Vs. 5/4 Decking: What’s the Difference?

Whether to install 2×6 or 5/4 boards is a dilemma many homeowners face when building or resurfacing their deck. Since they’re less expensive, 5/4 boards are a popular choice for decking because they have many benefits.

However, 2×6 decking also has its advantages, including the versatility of its use. Here we compare 2×6 vs. 5/4 decking boards and see which one is right for you.

By exploring the differences between these two board types, you can decide which suits your budget and purposes the best. Read on to find out more!

What is 2×6 Decking?

What is 2×6 Decking

2×6 boards have several purposes. Apart from decking, they can also be used for floors and wall finishes, not to mention for roof framing and furniture. In decking, they’re used as deck boards, deck joists, and railings.

For this purpose, the planks are pressure-treated to prevent rot and damage from mold, UV rays, insects, and other animals. Some manufacturers also offer 2×6 decking made from untreated softwoods and other materials.

Softwood boards are made from higher-quality lumber, and because of this, they offer a more appealing look. The initial dimension of 2×6 for these boards is reduced after planing, sanding, and drying, with the boards losing around 1/2″ in both width and length. They come in various sizes, but some are only available through special order, which makes them even more expensive.

2×6 boards are significantly thicker, which makes them less springy and less likely to warp, cup, or get damaged over time. However, they require stronger structural support, which further increases their installation cost.

On the flip side, these boards are easier to distribute because their span is wide and adjustable. As a result, you can put them at larger distances perpendicularly and diagonally without the risk of bouncing, springing, and moving, which may cause debris to fall between the planks.

What is 5/4 Decking?

What is 5/4 Decking?

Unlike its counterpart, the only purpose of 5/4×6 planks is to be used in decking – more precisely, to cover the base framework of a deck, inducing the joints and the beams. Because it’s intended for regular traffic, this decking is typically made from high-quality appearance-grade lumber or other top-notch materials.

5/4 deck boards also come in a number of options, including softwoods and hardwoods, which can be treated or untreated, and composite, metal, and PVC. 5/4 softwood boards that are more prone to damage from UV rays, insects, and humidity are pressure treated with chemicals. Decking made from lumber with a natural resistance to these elements doesn’t have to be treated before installation.

While 5/4 deck boards are usually less expensive, the type of material they’re made of and their treatment can affect their installation costs. It will also have an impact on how your finished deck looks.

After sanding, planing, and drying, these boards can also lose 1/2″ in width and length. Hard softwood boards are often rounded on their edges to give them a softer look. This makes them visually appealing, costlier, and even smaller.

The thinner depths of the 5/4 boards make them a more economical solution, which is why they’re more common than their counterparts. However, their span is smaller (particularly when placed diagonally). While this helps reduce their bouncing, it can also bump up the pricing.

2×6 Vs. 5/4 Decking Comparison

2×6 Vs. 5/4 Decking Comparison

Hopefully, now you have a better idea of the benefits and uses of these two types of boards. Now let’s dive a little deeper into their differences to see which one you should get.

1. Cost

Decking can be expensive, so most homeowners welcome any possibility to save money. The price of the boards depends on the type of lumber you use for your deck boards and their treatment. The pricing also varies from one manufacturer to another, so make sure to do your research before making a decision.

Nevertheless, if you’re on a tight budget, the most reasonable solution is to get the 5/4 boards. These cost at least $1.50 per linear foot and are typically ready-made for decks. 2×6 boards will cost you at least $2.44 per linear foot but can be used for different purposes. If you like their look and your budget allows you to get them, their quality and reduced number of joints will make up for the price difference.

2. Dimensions

The dimensions of 2×6 decking are 1-1/2” by 5-1/2”. While the nominal dimensions of 5/4 are 1” to 1-1/16” by 5-1/2”. Both types are available in 8’, 10’, 12’, and 16’ lengths. Some manufacturers will also produce 20’ and 24’ lengths for special orders in both formats.

However, there is a difference in the thickness between 5/4 and 2×6 boards. A 2×6 boards are 1-1/2” in thickness, whereas a 5/4 is between 1” and 1-1/16” thick. This can affect the distance the boards can span, their drying time, and their ability to remain stable.

3. Span

Decking joints are usually spaced 12”, 16”, or 24” on-center apart. How the joints are spaced affects the size of the lumber you need for beams and joints and their placement. The thickness of the boards also affects the spacing between the joints.

Since 2×6 decking can span up to 24” when laid perpendicular to the joists, you’ll need fewer joints to install them. When laid diagonally, 2×6 decking can span up to 16”. 5/4 boards only span 16” perpendicularly and only up to 12” diagonally. In either case, you’ll need more joints.

4. Spacing


The spacing between deck boards is one of the most crucial details you need to consider. Gaps as narrow as 1/8” are ideal for preventing debris and moisture from finding their way to the base, causing mold and rotting. 1/4″ allows better airflow.

This also reduces the risk of moisture damage but carries the risk of letting debris fall through. Larger gaps can also be hazardous for animals and children, who can get stuck and hurt themselves.

Therefore, the idea gap should fall between 1/8” and 1/4″. Both 2×6 and 5/4 allow for this, but you’ll need to ensure that the lumber is seasoned because wet wood shrinks as it dries, which can increase the gaps.

5. Condition

It’s also a good idea to check the condition of the wood. This includes checking knots are tight, the boards aren’t bowed and they also aren’t warped either. In terms of these factors, both types of board are the same and will both need a proper inspection.

6. Material

Both 2×6 and 5/4 decking can be made from different materials. The most popular choices are spruce, pine, cypress, cedar, redwoods, and fir. However, some manufacturers extend their offering to teak, mahogany, oak, and Ipe, not to mention composite, fiberglass, PVC, and metal decking.

That said, with wood and other raw materials, the material will only be durable if the treatment or finish applied to them is good quality too. To avoid any issues with molding, rotting, or structural damages, make sure to get top-quality products, regardless of whether you opt for 2×6 or 5/4 decking.

7. Shape


Both 2×6 and 5/4 boards have flat and broad, 5-1/2” surfaces on the top and bottom. However, their edges will often differ. The thinner 5/4 lumber makes it easier to create bull nose (rounded) edges. Reducing the corners lowers the risk of splitting and splintering.

It also makes it easier to remove any debris from between the boards. Plus, the water will shed of easier when it rains. 2×6 boards are thicker, which means their edges will remain square even if their corners are a bit rounded.

8. Style

The type of decking you use has an enormous impact on the overall appearance of your deck. While 2×6 and 5/4 look similar in texture, coloring, and material structure, the edges make a big difference. One has rounded edges that create more shadowing, while the other boasts square edges that make decks look more put together.

That said, 5/4 of boards are usually made for finishing deck surfaces. This makes them more conventional – and they generally look better because the lumber selected for them has fewer imperfections.

2×6 lumber is made for different purposes and may look less appealing. However, it can also be sorted out and treated to have a higher quality – but this will also come with a higher price tag.

9. Strength


Since 2×6 decking is 1/3 thicker than its 5/4 counterpart, it’s also much stronger. Its larger cross-sectional dimension provides more support and makes it safer for decks that need to bear a lot of weight. However, if your deck doesn’t need a heavy-duty load-bearing capacity, the thinner 5/4 boards will do as well.

10. Weight

The weight of the decking mostly depends on the material used for its construction. There are clear differences between 2×6 and 5/4 boards on this front too. And this is without considering the wood species, its moisture content, and treatment.

For example, 2×6 pressure-treated SPF boards weigh about 2.36lbs per linear foot. This is considerably heavier than the 1.59lbs per linear foot weight of the 5/4 lumber made from the same material.

11. Maintenance

This is another area where both boards are going to be the same. They both will require a similar level of maintenance to keep them looking their best. That being said, the 5/4 can be slightly more prone to damage considering they are a little thinner.

Final Thoughts

In order to choose between the 2×6 and the 5/4 deck boards, you must factor in all the differences. Apart from obvious sizing issues, the two also differ in pricing, thickness, and the number of span joints needed for their installation.

For example, if you’re going for the most obvious solution, you’ll probably get 5/4 boards, as these are made exclusively for decks. With these, you’ll gain the benefit of paying less, for both the boards and the installation of the joints.

However, if you want a more versatile look and prefer spacing joints at 24” instead of 16”, you’ll need the 2×6 boards. While these costs a little more, they’re also thicker and provide more support. Plus, with them, you’ll need fewer joints, which allows you to save money on the decking.

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