There are many steps to building a deck, and one of the last is installing the floor.
If you’re wondering how to space, measure, or attach boards, our tutorial will show you how. We are installing a redwood deck floor over the frame and joists we just built.
How to Install a Deck Floor
Step 1: Measure
Run a tape measure along the outer frame where the two sides of your deck run lengthwise with your joists.
Mark every 12” along the outer frame.
Mark every 12” along the outer frame on the other side as well.
Step 2: Mark the Joists Every 12 Inches
Run a chalk line, matching the ends up with every 12” mark, and snap it across the joists every 12”.
The chalk lines will provide you with a gauge to square up against. It will keep you on track, so you don’t end up slanted at the end of your deck.
Step 3: Decide Where Your First Board Will Go
If you have a curved aspect of your deck, start at the outermost part of the curve. (See this tutorial on laying a curved deck floor.)
Also, consider the possibility of abnormalities within the deck floor. For example, this electrical conduit (pipe) must come up through the corner of the deck to enter through the house wall.
So, we measured, marked, and drilled the hole for that pipe in our first board.
(Of course, if your obstruction comes in the middle of your deck, you’ll have to deal with that when you get there. Unless you want to start at the point of obstruction and work your way outward. It’s a judgment call you have to make based on your specific setup.)
Sand the edges of the hole so the top of the deck floorboard is smooth.
The board is now ready for us to place.
Step 4: Install Your First Board
To lay our redwood deck floor with 2×6 pieces of wood, we will be using a Camo brand deck spacer. Once you use this tool, you’ll never want to use anything else to build a deck.
It works by squeezing the lever upward, which extends outward two metal spacers at either end of the tool.
Keeping the lever squeezed, place the Camo deck spacer on the redwood 2×6 at the point that is both parallel and centered over a joist. Release the lever to contract the two metal spacers, and clamp the deck spacer tool in place.
Then use the appropriate size Camo screws (in this instance, 2-3/8” screws for a 2×6 deck floor) to screw into the holes on either side of the deck spacer.
Installation Tip: Using a Camo Deck Board Spacer and Installing Level Boards
Now, let’s talk about technique. We found it most effective to begin at the most stable/immovable side of the deck. In this case, that is the house wall side.
Clamp the deck spacer above the frame here, and screw the redwood board in place, leaving about a 1/4” gap between the end of the board and the house.
Be sure the obstruction is threaded up through the redwood board, if applicable, before attaching.
The method we found most effective involves three workers per board. Two workers use a deck spacer on neighboring joists, while the third worker levers the board’s end to keep it parallel.
(Note: These are 16’ boards to cover about a 13’ deck span because whenever possible, it’s best to have seamless deck floor boards. So there is about 3’ of excess at the end of each board. )
Use a pry bar to push or pull the end of the board so that the Camo deck spacer is snug.
As you work your way outward from the house (or your most stable deck side), you will have the two-deck spacers set, then the pry bar set and pushed or pulled as needed to keep the board snug. Then you’ll insert the screws through the deck spacers and release the pry bar.
Remove the Camo deck spacers and repeat the setup on the next two joists down the line.
The third worker often doubles in duties of horizontal pressure, with the pry bar set and secured, as well as vertical pressure, standing on the board so it’s flat against the joists or frame.
Here’s another instance where, near the end of the 2×6 board’s installation, the third person will stand between the two deck spacers in order to secure the board against the joists.
Installation Tip: How to Straighten Curved or Bent Deck Floor Boards
Sometimes boards will be bent just enough that it’s hard to use the deck spacer. When this happens, use wooden shims to widen the gap enough for the deck spacer.
Place the deck spacer, so it is flush against the top of your redwood board.
Then you can either remove the shim and install the screws or keep the shim there while you install the screws. It doesn’t make much difference.
An alternate method for creating enough space is to use a small crowbar between the two boards. Pull or push it to give your deck spacer some room, then remove the crowbar after the spacer is in place.
Working your way from the house (or the most stable side) down to the other edge of the deck allows you to use the end of your redwood 2×6 as leverage for pushing/pulling it into place. Remember that wood isn’t precisely straight, and you can manipulate it to a large extent to lay where and how you want.
Step 5: Work Your Way From One End of the Deck to the Next
You can see here the line of Camo screws installed along this joist. That’s what makes using a deck spacer like this so wonderful – the proof of installation is almost invisible when all’s said and done.
If you want your deck floor to look seamless, use a tool like the Camo Spacer to screw the boards down.
Step 6: Allow Your Boards to Overhang Your Deck
Allow the ends of your boards to overhang the edge of the frame where possible. Be sure to use the deck spacer on both of your doubled-up outer deck frame pressure-treated boards.
If the overhang distance is too great or you need to use the excess lumber, use a circular saw to cut the ends off the outside edge of your board. Leave an inch or two of overhang so you can do a final precision cut along your deck edge before you start to trim.
Installation Tip: How to Work Around Obstructions
If you run into obstructions, like this 6×6 cedar pergola post coming up through the deck floor, you may need to use large clamps instead of the pry bar to keep the board in place.
It’s easy to chisel bits of the board as needed. Simply use a jigsaw, then hammer and chisel the rest of the wood out. The pergola post infringed on the next redwood board in this example, so we had to remove a small sliver.
Then use the Camo deck spacers above the joists and/or frame to keep the board in place before mounting.
Always put downward pressure on the board and/or the Camo deck spacer as you’re installing the screws. You never know when a board is lifted off the joist a little.
We will trim the bottom of the pergola posts, so we didn’t sand or finish the edge. The important thing is that the 2×6 redwood board fits around the pergola post, and the board maintains its parallel layout for the rest of the deck floor.
Installing a deck floor is a process of working methodically, from stability outward. In this example, we worked from the board closest to the concrete steps outward, with each board being secured from the left (secured side) to the right.
Step 7: Install Your Outermost Flood Board
When you get to the very outer floor board, measure the widest distance from the second board’s edge to the outer edge of your frame. (Hopefully, this will be the same distance all across, but in case it’s not, make sure you take the widest distance.)
Mark this distance, and run the last board through a table saw to create the precise width you need. Install in the same way, with Camo deck spacers keeping the space and predrilling/screwing on the very outer edge.
You’ve just completed laying the redwood deck floor.
Redwood is just beautiful on a deck floor.
While you may still want to add trim, you can start to envision what a gorgeous asset this redwood deck will be to your home, yard, and life.
With the floor installed, you’re almost ready for stain and sealant.
We hope you enjoy installing your own redwood deck floor and that the end result is something you can use, enjoy, and be proud of.