How to Install Wood Deck Boards
Installing wood deck boards on your deck adds to the beauty, functionality, and value of your home. Wood deck boards can be installed using just a few basic tools. Dimensional lumber deck boards, available at nearly every home center or lumberyard, are among the least expensive flooring materials for your outdoor deck.
Before You Begin
Pressure-treated deck boards are inexpensive, insect-resistant, and highly durable. Two-by-sixes or thinner 5/4 x 6 boards work well. Choosing rounded edges rather than square edges minimizes splintering. Longer boards, up to 16 feet, reduce the number of seams and butt joints—major avenues for water wicking and wood rot.
A common way to install wood deck boards is by driving screws vertically, down through the faces of the boards. This simple, straightforward method keeps boards more secure than with nails. This method can also help to straighten deck boards that are slightly warped.
The downside of this method is that the fasteners are visible, plus water can pool on top of the fasteners, leading to premature rotting.
Another way to install wood deck boards is by driving screws at a 45-degree angle, rendering the fasteners nearly invisible. This method is a bit more expensive since a special deck board jig must be purchased (about $50). The raked-tip fasteners carve out the wood, reducing the possibility of cracking and splitting.
One downside of using hidden fasteners is that the smaller heads of the fasteners tend to pull through the wood more than with traditional bugle head deck screws.
Use spacing tool
Drill and jig required
When to Install Wood Deck Boards
Wood deck boards that are still green or insufficiently kiln-dried benefit from four to six weeks of drying time in the sun before installation. Green wood will shrink as it dries. Deck boards should have a moisture rating of 19-percent or less. Check for moisture content with a moisture meter.
It's best to install wood deck boards in dry, warm weather. If installing in rainy or humid weather, make sure to minimize the space between the deck boards because they will contract over time.
An electric circular saw and electric drill are the main tools used for installing wood deck boards. Observe the manufacturer's safety instructions for using these tools. If the deck is elevated, take precautions to avoid falls.
What You'll Need
Equipment / Tools
- 1 circular saw
- 1 electric drill
- 1 tape measure
- 1 chalk snap line
- 1 drill bit set
- 1 star-head drill driver
- 1 deck board spacing tool
- 33 wood deck boards, two-by-six or 5/4 x 6
- 1,000 decking screws, 3-inch or 2-1/2-inch
- 500 hidden fasteners (optional)
Check and Fix Structural Elements
Check that the deck's structure of joists, beams, rim joists, and blocks are in good condition. Repair as needed. Existing decks that are being re-floored usually will need some type of repair work. After the decking materials have been installed, it's more difficult to fix these lower structural materials.
Plan the Decking Layout
This 15-foot by 15-foot deck is designed to utilize full-length 16-foot decking boards laid on a deck structure adjoining a house, assuming joists are spaced every 16 inches on-center. A total of 31 boards is required, with two extra as 5-percent wastage. Plan to lay the deck boards parallel to the house.
Install the First Deck Board Row
Lay the first deck board at the end of the deck that is opposite of the house. It's best to start at the far end because this end must have a full-width board due to the overhang. The board adjacent to the house has no overhang, so it can be ripped down if necessary.
Space (Gap) the Wood Deck Boards
Proper wood deck board spacing is 1/4-inch to 3/8-inch. For face fasteners, use the pair of spacing tools to gap adjacent boards. It's common practice to install green deck boards with no or little space since the boards will shrink over time.
Attach Wood Deck Boards (Face Fastening)
Using the electric drill, fasten each deck board with two screws per support point. For boards that are prone to splitting, start with a pilot hole. Sink the head of the screw so that it is flush with the deck surface.
Create pilot holes at butt ends. Butt end screws need to be close to the end of the board in order to contact the support point below. Ends are more prone to cracking than other parts of the board.
Attach Wood Deck Boards (Hidden Fasteners)
Attach the deck boards with two hidden fasteners per support point. Clamp the jig over the board, centered over the support point. Drive one fastener on each side of the board. For warped boards, it's sometimes necessary to supplement hidden fasteners with face-driven fasteners.
Butt Wood Deck Boards (Optional)
For decks that extend beyond the length of the boards, wood deck boards are pieced together end-to-end. Board ends should land on a joist. Two end-to-end deck boards will rest on the same joist, creating a butt joint.
Space board ends with the expectation that the wood will not expand or contract in a length-wise direction. So, any end-to-end board gap you place should remain. Board gaps are placed on the long ends of boards because wood fibers will swell and shrink in a width-wise direction.
Stagger Wood Deck Boards (Optional)
When two adjacent rows of deck boards have butt joints, the joints should be staggered. So, the butt joints should not rest on the same joist. Space them out so that they rest on different joists.
Pre-Cut Last Deck Board (Optional)
For a deck that's 16 feet wide on top, do not cut the boards. This assumes that the distance between perimeter rim joists is 15 feet, 10 inches—that is, a deck flooring overhang of 1 inch on all sides.
For deck boards that need to be cut, be sure to cut the board nearest to the house before attaching it to the deck. All other boards will be cut after they have been installed. The board nearest to the house needs to be pre-cut because the circular saw will not cut against the house.
Trim Excess Decking (Optional)
This deck's boards do not need to be cut. For decks that require cutting, snap a chalk line on the end of deck boards that need to be trimmed. With the circular saw, cut the deck boards to length.
When to Call a Professional
Basic decks can be built by a homeowner. But when decks have complicated features like staircases, railings, multiple levels, or elevated decks, it's often best for a professional deck contractor or general contractor to build the deck. With deck flooring, this is especially the case when you choose tropical hardwoods like ipe, which use stainless steel clip fasteners.
All decks—even simple ground-level floating decks—must adhere to building codes specific to decks. Professional deck builders are experienced at building decks to code, ensuring that the deck will be safe and solid.