How to Make an Outdoor Spiral Bench
A bench doesn’t have to be a rectangle or square. Learn how to build a three-sided spiral bench with built-in planter boxes.
Spiral Planter Bench 01:00
- (3) 1x6 x 8'
- (7) 2x4 x 8'
- (8) 1x4 x 8'
- 3” decking screws
- exterior paint
- miter saw
- measuring tape
- speed square
- circular saw
- palm sander
- optional: landscape fabric
Skill Level: Advanced
Estimated Time: 1/2 day
Estimated Cost: $275
Assemble Seat Frames
Build the frames using three 2x4s. The frames will be 17-1/2” across to match standard seat depth.
- Cut one board to 20-3/16” (both ends at 30-degrees)
- Cut one board to 24-3/8” (one end at 30-degrees)
- Cut one board to 34-1/2” (one end at 30-degrees)
- Cut one board to 17-1/2” (both ends straight)
(see Image 2).
Attach Seat Frames
Fasten the three identical frames together to create the seat base. Use bolts for a strong joint.
Make Seat Surface
Cut five 1x4s with the same 30-degree angle on one end. Attach these cut 1x4s flush to the edges of each section of the 2x4 frame. Repeat for the other two bench sections.
Trim the Ends
Use a circular saw to cut off the excess 1x4s from the end of each section of bench. This is an easy way to ensure your bench seat is flush all the way around.
Flip the bench over to attach the legs. Make the legs from 2x4s cut to length at about 17” so your bench will sit about 18” off the ground. (Standard seat height ranges from 16” to 19”.) The six legs will attach using screws (be sure to pre-drill) on the outside corners of the frame on each bench section. Add a leg in the middle of the spiral for additional support.
Paint or Stain
Use a sander or hand-sand all the edges smooth. Paint the bench using an exterior-grade paint (we used a paint with built-in primer).
Build Planter Boxes
This step is optional; you can leave the bench as-is. We chose to cap off the ends with planters. To make one box, cut two 17-1/2” pieces from a 1x6 for the back and front of the box. For the sides, cut two 5-1/2” pieces from a 1x6; for the bottom of the box, cut a piece of 1x6 to 16”. Assemble using deck screws. Paint or stain the boxes to match the bench. Line the boxes with landscape fabric, stapling it in place. Then fill with soil and your favorite plants.