You’ve probably heard the term “fascia,” but you may or may not know what it means or what purpose it serves on your deck. Fascia is a finishing board that is installed around the perimeter of your deck. Your deck could probably survive without fascia, but it offers some protection, and your deck will look better with it.
Fascia is primarily installed to achieve a seamless appearance. It also covers joists and hides uneven edges on the deck. It masks gaps and holes in your deck, giving it a nice, even finish. Some people install fascia boards in colors that contrast with the rest of their deck for a pleasing aesthetic.

(cmesker / pixabay)
If you plan to use a fascia board for your deck, you may use pressure-treated lumber or something like cedar or redwood, both of which have natural rot-resistant properties. You might also opt for composite fascia board made from a combination of plastic products and wood fibers. These composite boards can be very sturdy and rot resistant.
Things to Consider Before Installing Your Fascia Board
- Decide on whether to use pure hardwood or composite fascia.
- Ensure proper blocking and spacing of your deck joints and check to see if the base and understructure of your deck are holding up well and are in good condition.
- Make sure your deck boards of choice conform well to the final deck design.
- Make sure that the fascia boards are well-constructed.
- Measure the whole perimeter of your deck to get an estimate of how much fascia board you will be needing (with allowances).
- Cut the boards in a way that they fit snugly around the base of the deck.
Note: Remember that the fascia boards are subject to expansion and contraction depending on the temperature. As our Colorado custom deck installers can attest to, it will expand when exposed to Colorado’s high summer temperatures and contract during winter weather.
Installing Fascia Board
Get the right screws. We recommend 1 ½-inch trim head screws with a clean shaft so that they don’t make that big of a hole.
Space screws correctly. The general rule here is 3 screws for every 12 inches of fascia board.
Start with your outside corner. You’ll have two boards with a 45 degree angle cut meeting together. Don’t stress out if they don’t meet exactly. We’ll give you tips for dealing with that later.
Start your screws at the seam and work your way over to the end of the board. Again, you want to use 3 screws per 12 inches of wood.
Inside cuts. We’ve told you about the outside cuts. What about the inside cuts? For the inside cuts, you don’t have to worry about that 45 degree cut because it’s not visible from the outside. Make sure the inside cut is just past the corner so you can get a nice tight seam.
Don’t lock inside pieces in. Don’t lock in that inside corner or you could end up with buckling later due to expansion. Leave about a 3/4-inch or 3/16-inch gap.
Fill the gaps with wood stain. You’re probably wondering what to do about that gap that you can see through. Here’s a trick. Take some wood stain that is as dark or darker than the fascia. Paint the board underneath in that color, and you won’t even be able to notice the gap. Easy!
Add more screws. Since you’re not locked in like you were with your outside corner, you can start your screws wherever you want. You can work from the seam on down the board or start in the middle and work out toward the edges of your board.
Fine tuning. Take a look at your work. If your outside corner is a little messy, go over it with a belt sander. You can also add a corner seam guard for a clean finish. If you are concerned about gaps, you can add a bridge piece over a butt joint. (Just make sure that you don’t screw it into the fascia board but anchor it to the deck wood underlying the fascia.) You should also make sure you allow for some give on either side to account for the inevitable expansion.
Additional Information on Choosing Your Fascia Material
Apart from looking great, the fascia board also offers some protection against rain, snow, and searing sun. Make sure that you choose the board material that will best shield your Colorado deck against the elements.
Types of composites include PVC as well as Trex Decking and Hardi Plank. Trex is made up of 95% recycled materials containing sawdust, wood, recycled plastic, and other everyday household items like paper towels, grocery bags, and so forth. Another contender in the composite family of fascia boards is Hardi Plank. It combines cement, sand, and other fibers that make it extra durable in extreme weather.
Fascia isn’t hard to install and will give your Colorado deck that beautiful finish that you can enjoy and feel proud to show off to others.