A note from Kirsten: I'm always excited to welcome our friend (and one of Dunn DIY's regular contributors) Todd Dermody. Todd has been with Dunn Lumber for over 35 years, and brings a lot of helpful insight with his experience. 

You might not immediately picture the Pacific Northwest when you think of a boardwalk—which evokes iconic beaches, roller coasters, and carnival games. But in reality, our climate is a great candidate for a boardwalk—especially one built with composite decking materials from Deckorators®. I'm so glad we got the chance to give Todd's yard this cool, long-lasting upgrade.

Here's Todd!

While traveling back east last summer and checking out the “old stomping grounds” of my dad and granddad, my wife and I saw many boardwalks along the New England seaboard. Some were elevated, but many were virtually at ground level. When we decided to address an area of our yard that we weren’t happy with, the idea of a boardwalk sprung to mind—as a way of improving our yard (while reminding us of my forefathers). We modified the design to fit our particular application in the Pacific Northwest, and now have something which will always remind us of our time on the New England coast.

This side of our yard is shady, doesn’t grow grass well, and can be muddy sometimes. A boardwalk provides a walking surface that is slightly above ground and will remain solid year-round.

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Step 1: Remove Existing Grass

If you have a small area of sod to remove, you can use a square head shovel. Larger areas are more easily tackled with a sod cutter (which has a horizontal blade that cuts underneath the blades of grass).

Sod cutters can be rented from a local tool rental company. For this project, we used a power sod cutter from our friends at R&R Rentals

There are also manual sod cutters that look a bit like a plow, but instead of a horse or ox pulling it, you kick it forward. (If you can’t picture that, there are plenty of YouTube videos that show how it works.) The powered, self-propelled sod cutters take the manual work out of cutting sod. Keep in mind that these are heavy machines and most easily transported in a pickup truck.

The first part of removing the sod is cutting it. Regardless of what method you use, you’ll then need to remove it. Roll it up into a manageable size, and remove the sod from your work area.

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Step 2: Roll Out Landscape Fabric

Next, rake the dirt so it’s reasonably level, and lay landscape fabric over it. This will help keep grass and weeds from growing up through the boards of your boardwalk.

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Step 3: Lay Down Sleeper Boards

After placing the landscape fabric, we laid pressure-treated 2” x 6” lumber to act as sleepers (and distribute the load of the walking surface). This pressure-treated lumber is rated for ground contact. The sleeper boards run the length of our boardwalk while the actual walking surface boards run perpendicular to them.

The length of our boardwalk was 40 feet, so we needed to splice together 2” x 6”s end-to-end. Since we wanted the spliced boards to act more like one long piece of wood and not have the joined spot act like a hinge, we did two things at the joints:

  1. Cut the ends of the boards at 45-degree angles and fastened with screws. This is called a "scarf joint."

  2. Attached tie straps along the sides of the 2” x 6” at the splice.

Note: When you cut pressure-treated lumber, treat the cut end with a liquid wood preservative to maintain the integrity of the treatment.

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After laying our sleepers out lengthwise, we leveled them with gravel as necessary. You’ll want your supports to be relatively level, but have a bit of slant in one direction to allow rain to drain away more easily from the boardwalk planks.

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Step 4: Gather Boardwalk Boards

Now we’re ready for the walking surface! For this particular application, we wanted to use a composite board that would be easy to keep clean. We also wanted a color that looked like weathered wood, to add to the seaside boardwalk feel of the path. We chose Deckorators® Vault decking in the color "dusk.”  

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Step 5: Cut Vault Decking Boards to Length

Vault decking is manufactured in a way that gives it both a great look as well as properties where it won’t absorb water, which is important for our application since we’re virtually at ground level! We wanted our boardwalk deck boards three feet long, so our first step was to cut the Vault decking down from longer lengths into three-foot pieces using a chop saw. If you’re using composite lumber for your project, consult the manufacturer’s website or related literature for cutting tips (such as what type of blade to use).  While we used a Chop Saw for this project, a circular saw works too.

Like most lumber, composite boards are not necessarily precision cut, so a 12’ board is not always an exact 144” long. Keep that in mind and measure your boards before you cut. Don't assume, for instance, that cutting a 12’ board in half will give you two pieces exactly 6’ long.

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As you lay the boards, stop every now and then to check them with a level, and make sure they’re all laying relatively flat. If you get to one that’s a little bit off: stop, adjust the height of the sleeper boards as necessary, and then continue with the project.

The deck boards should ideally have a little slant, so water is less likely to puddle up on them. It won’t hurt the board to have water on it, but the slant will definitely make it a nicer surface to walk on, especially with all the rain we get here in Seattle.

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Step 6: Attach the Walking Surface

After cutting our boards, we were ready to fasten them down to the sleeper boards. We chose to use the Stowaway Hidden Fastener System from Deckorators®. This meant most of the boards we ordered were grooved boards to accept the Stowaway Hidden Fastener Clips. Stowaway Hidden Fasteners not only anchor the boards down, but automatically space them at the same time. Quick and easy! 

The fasteners come preloaded with a screw (and a driver bit is provided too). The heads of the screws are black, so they virtually disappear in the spaces of the boards. A power drill will work fine to drive these screws in, but an impact driver will make quicker work of the task, since an impact driver provides much of the downward pressure that you would otherwise have to provide yourself.

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It’s time to attach the boardwalk planks! For a cleaner look, we wanted our first and last board to be ungrooved and have a clean, square edge showing. For those two planks, we ordered the non-grooved Deckorators® Vault decking.

We laid down our first board (but left it unattached) in order to find the spot to start using the first grooved board. On our first grooved board, we cut off one wing of the hidden fastener—since it will butt up against the non-grooved board that starts our pathway.

After fastening that side of our grooved board, we put three more fasteners in the other groove, slid the next board into place, zipped in the screws, and repeated that down the length of our boardwalk.

Similar to the first plank, we allowed space for the last plank (which is ungrooved) and cut off one wing on the hidden fastener of the last, grooved board.

To attach the first and last boards (the ungrooved ones) we set the boards up against the neighboring plank’s hidden fastener (with the wing removed) and then screwed them down through the face of the plank. To secure the boards, we used Screw Products Inc.’s C-DECK Composite Deck Screws, which are specifically designed for composite decking.

Why use a screw designed for that? Not only do these screws come in 23 colors to match any decking surface, but the top threads of the screw pull down any fibers that the lower threads release as they go in, resulting in a smooth, flush, countersunk finish. Regular screws tend to “mushroom,” leaving composite material around the screw head. (We’re not talking “sawdust” that can easily be swept away, but a “mushroom” of composite material that is pretty unsightly.) The C-DECK screws worked perfectly, and made us look like pros.

With the boardwalk done, we’ve been able to enjoy a part of our yard that we had avoided for quite some time. It’s not exactly the New England seaboard, but this beautiful boardwalk definitely brings a little bit of that feeling home.

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