How to update your old deck with new composite deck boards
If your old wooden deck is splintered, fading, or just plain falling apart, it might be time to replace it. We chose to upgrade the deck with Trex composite deck boards from Lowe’s. Trex boards are low-maintenance, weather-resistant, and come in nice colors that mimic natural wood without all the hassle of staining or sealing. In this tutorial, I’ll walk you through how we replaced our existing deck boards with Trex. It’s easier than you think!
Why Trex?
- No staining or sealing required.
- Comes in several colors and different length boards.
- Resistant to rot, mold, and fading.
- Easy to install.
- Long-lasting investment (with warranties up to 25 years).
What You’ll Need:
Materials:
- Trex composite deck boards (we chose the color “Clam Shell”)
- Trex hidden fasteners (for a clean, screw-free surface)
- Pressure-treated lumber for any joist or railing repairs
- Wood screws, lag bolts and washers for railings
- Wood (or PVC) lattice
Tools:
Download my free DIY tool guide HERE!
- Tape measure
- Circular saw
- Miter saw
- Drill/driver with bits
- Pry bar
- Hammer
- Level
- Safety gear (gloves, safety glasses, ear protection)
Tip: Order 10% extra Trex boards to account for cuts and mistakes.
How Much Did It Cost?
This was a small 8’x10′ deck for reference.
- 1x6x12 Trex Deck Boards Qty 17 x $23.88 = $405.96
- Trex Universal 1″ Black Hidden Deck Fasteners 50 sq ft (94 Pack) 1 x $39.98
- 4′ x 8′ Pressure Treated Spruce Wood Traditional Lattice 3 x $29.98 = $89.94
TOTAL COST: $535.88
Step 1: Remove the Old Deck Boards
Start by pulling up your old deck boards with a pry bar. If they’re nailed down, you may need a hammer to loosen stubborn boards. These nails were so old, many of the nail heads popped off and were difficult to remove. Most of them were rusted out. Removing the old nails and deck boards was honestly the most difficult part of the entire project! We also had to remove all the railings first in order to get the old deck boards off. The railings and joists were in good shape so we didn’t have to replace much of that at all.
Step 2: Prep the Frame
The best part of the Trex system is that the fasteners space the boards out for you! All we had to do was cut the boards down to size. They come in different lengths too which is helpful!
Trex needs proper spacing to allow for expansion so you’ll want to make sure your joists are spaced no more than 16 inches apart (12 inches if you plan on a diagonal pattern). Run a level across the frame and add shims if needed to create a flat surface. The fasteners screw into the joists between the boards.
Step 3: Plan Your Layout
Before you start screwing anything down, lay a few boards across the deck to see how they fit. Trex boards come with a finished edge, so think about which side will be most visible (the clean edge should face out). We kept the orientation of the planks exactly the same as the old wood boards so it was very simple and easy since they were the exact same width. Basically it was just out with the old, and in with the new!
Step 4: Cut the Trex Boards
Measure and cut your boards to length using a miter saw. A fine-tooth blade will give you a cleaner cut on composite material. If you cut them slightly longer, you can take a circular saw and run it down the edge and trim down all the boards so they’re a perfect fit.
Safety Note: Composite decking can get hot, so when cutting, work in the shade if possible.
Step 5: Install the First Board
Position your first board flush with the outside edge. Secure it with screws or Trex hidden fasteners. Make sure it’s perfectly square and level—this first board sets the tone for the entire deck. We worked from out to in, removing a couple boards at a time then laying down a new board and progressing towards the house.
Step 6: Use Hidden Fasteners for a Seamless Look
Trex’s hidden fastener system slides into grooves on the side of each board. Place the fastener into the groove of the first board, screw it into the joist, then slide the next board in place. Repeat across the deck, screwing them into each joist. This was so easy and fun to do! I love that you don’t have to screw through the boards with these fasteners. It looks really nice and holds the boards securely while making them evenly spaced.
Step 7: Trim and Finish
Once all boards are installed, trim any overhanging edges with a circular saw for a clean, uniform look. Add Trex fascia boards or edge trim if desired. We opted to reinstall the existing railings since they were in decent shape and not install any fascia. Plus, we were adding lattice to the outside so the edges would be covered anyway.
Step 8: Add Lattice
We added pressure treated wood lattice around the outside to make it safer for the kids to be out on the deck. It comes in white PVC also but we liked the look of the wood. It can also be stained to match! The lattice comes in 4×8′ pieces so we just ripped them down to size with the circular saw and screwed them in to the railings and base. Easy peasy!
Step 9: Clean and Enjoy!
Give your new deck a quick wash to remove any sawdust, then grab a couple chairs, a cup of coffee and enjoy your beautiful, maintenance-free, upgraded deck!
This was a surprisingly easy project that you can do in a weekend! Do you have a deck that needs updating? Let me know if you try this!
Until next week, happy DIY-ing!
-Selene Builds Things
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