Drag to turn it. 3D model render, drawn from the plan itself; photos of the finished piece are coming soon.
Harbor Sofa
A three-seat outdoor sofa built the same way as the Harbor Lounge Chair: sled sides to the floor, a seat box that hangs between them and a back raked at 15°. Ribs under every cushion seam keep the long slats stiff. Every board fits on an 8 ft board, and every screw was checked in 3D to land in solid wood. Both backs are in the plan: straight-cut, or mitered with crisp 15° ends.
- Skill
- Level 1–2
- Build time
- About 10 hours
- Size
- 82" × 35" × 30¾"W × D × H
- Lumber
- 17 boards, all 8 ft
- Straight-cut backsquare cuts only
- Mitered back15° ends, level top
Each with its own 3D guide and PDF. Same boards, same screws, same shopping list.
Make it a set: Harbor Lounge SetHarbor Sofa + Harbor Lounge Chair + Harbor Ottoman plans for $59Save $18See the free 3D build guide previewGive it as a giftBuild-ready or your money back. If anything in the plan doesn't work as drawn, email us within 30 days for a full refund.
You buy the materials at Home Depot, not here. Cedar: from $545. Cushions extra, from $64.
- Printable plan and interactive 3D build guide
- One-trip Home Depot shopping list
- Yours to keep. Build it as many times as you like
37 parts, only 5 lengths.
Every part gets a letter you pencil on its end. The drawings, the cut list, the cutting diagrams and the 3D guide all use the same letters, so you always know exactly which board you are holding.
- DrawingsFront, side and top views with dimensions
- Cut listEvery part by letter, board and length
- Cutting diagramsWhich part comes from which 8 ft board
- 8 stepsEach with time, check and common mistake
Try the build guide before you buy.
The first 2 of 8 steps are free. It’s exactly what you’ll follow in the garage, on your phone or laptop.
- Watch each step build itself, board by board, screw by screw.
- Spin and zoom the model with your finger or mouse.
- Tap any board to see its letter and cut size.
Try steps 1–2 freeOne list. One trip to Home Depot.
| Item | Qty |
|---|---|
| 2x6 × 8 ft pressure-treated pine, #2 Prime | 3 |
| 2x4 × 8 ft pressure-treated pine, #2 Prime | 14 |
| 2-1/2" exterior wood screws, rated for treated lumber (hidden joints) | 60 (1 × 1 lb box) |
| 2-1/2" exterior trim-head screws, rated for treated lumber (slats, arm tops) | 74 (1 × 1 lb box) |
| 5" structural wood screws (GRK RSS or SPAX) | 20 (1 × 25-pack) |
| Behr semi-transparent stain & sealer, Cedar Naturaltone | 2 qt |
- Estimated build cost
- $190–$210
- BudgetHampton Bay CushionGuard 24 × 24 deep-seat setSeat and back, per seat$64
- PremiumGreendale Sunbrella 24 × 24 deep-seat setSeat and back, per seat$112
- Pick #2 Prime boards and sight down each one. Take the straightest and grab one spare of each size.
- Treated pine comes wet. Stack the boards flat with scrap spacers between them, out of the sun, for 2–3 weeks before you cut. Dry boards don't shrink or twist after you build.
- Use screws labeled for treated lumber (most coated exterior screws are) and galvanized brackets.
- Sand the faces and edges smooth, then stain once the wood is dry. A cedar-tone stain gives it the honey look in the photos.
- Wear a dust mask when cutting and sanding treated wood, and never burn the scraps.
Estimates based on typical Home Depot prices; your store may vary. Same cuts and same steps in either wood.
8 steps · about 10 hours
- 1Cut the partsFree in 3D1 hr 15 min
- 2Build the two sidesFree in 3D1 hr
- 3Build the seat box40 min
- 4Stand the sides and hang the box40 min
- 5Add the cleats and seat slats1 hr 15 min
- 6Add the back1 hr
- 7Cap the arms20 min
- 8Finish and add the cushions1 hr + drying
Good to know
What's the difference between the two backs?
Both come with the plan. The straight-cut back uses only square cuts: a small spacer block on each arm sets the 15° lean, so you never measure an angle. The mitered back cuts both ends of each back stile at 15°, so the stiles sit flat and the top of the back is level. It looks a little crisper and needs a miter saw. Same boards, same screws, same shopping list.
How big is it?
82 inches wide, 35 inches deep and about 30-3/4 inches tall at the back. It seats three on standard 24 × 24 deep-seat cushions.
Which cushions does it use?
Three standard 24 × 24 deep-seat sets, bought ready-made: about $64 a seat for Hampton Bay CushionGuard, or about $112 for Sunbrella.
How many cut lengths are there?
Five. The long front, back and slat boards are 72-1/2 inches, and the rest match the Harbor Lounge Chair. Every cut except the optional mitered stile ends is a straight crosscut.
Which tools do I need?
A drill/driver, a miter saw or circular saw, a tape measure, a speed square, two clamps and a sanding block. Every joint is wood on wood with screws: no pocket holes, no glue-ups, no brackets.
Can I build it in pine to save money?
Yes. The plan comes with a second shopping list in pressure-treated pine, with the same cuts and the same steps. Pine needs a couple of weeks to dry and a coat of cedar-tone stain, but costs about a third as much as cedar.
Can one person build it?
Mostly. Every part can be lifted by one person and the sides are built flat on the floor. A second pair of hands helps when you hang the seat box between the sides.