Round and Curved Decking Installation

How to install a curved deck with Hyperion® composite decking.
Despite its straight and rigid nature, it is possible to build a curved deck with composite decking. The decking boards will need to be cut to a curve using a circular saw.
Composite fascia boards are thin and flexible enough that they will bend around the curve to give the edge a clean finish.

Round Deck Installation

Step 1

Lay the joists

Prior to building the substructure, measure around the inside of the curve and ensure the substructure is in place at regular enough intervals to hold the fascia to the curve. Cut your joists to the desired curved shape:
  • Exact angles will depend on the desired position of the decking boards; it is possible to lay decking at up to 45┬░ along joists, although joist spacing will need to be adjusted based on this.
  • It is important to keep the joists as close to perpendicular along the curved edge as possible.

Step 2

Brace the gaps

Using straight lumber, brace the gaps between the joists, cutting the ends at angles to follow the curve.

Step 3

Install deck boards and fascia

Finally, after installing the decking boards as normal, a composite fascia board can be used to create the outer curve.
  • Gently bend the fascia board around the curve, screwing it into the ends of the joists using a standard countersunk wood screw. This is very much a two-person job, where one person can apply pressure while the other is screwing the fascia in place.
  • Ensure to fix the fascia board to the joists rather than the braces.
Another method of finishing a circular deck is by heating the fascia boards. Due to the plastic content, they will become softer and easier to bend to a variety of shapes. However, it is technically difficult to do without damaging the boards. It also requires specialist equipment and does not give significantly better results, thus we do not recommend this option.

Keep in mind that you can do either an inwards or an outwards curve for your deck. And it can also be incorporated into stairs.