If you have narrowed your shortlist to two specific designs, this is exactly the kind of decision where a side-by-side spec view saves a weekend of second-guessing. Both plans below are complete, code-aware DIY builds, but they differ on the things that matter for a backyard project — total cost, raw labor hours, footprint, and the wood species on the cut list.
Side-by-side specs
| 12x16 ft Hot Tub Pavilion Plan | 3x4 ft Pergola Archway Arbor Plan | |
|---|---|---|
| Category | Pavilions | Arbors |
| Style | Hot Tub Pavilion | Pergola Archway |
| Footprint | 12x16 ft (192 sq ft) | 3x4 ft (12 sq ft) |
| Wood species | Black Locust | Black Locust |
| Roof finish | aluminum louvered system | retractable canvas awning |
| Difficulty | Advanced | Intermediate |
| Build time | ~138 hrs | ~33 hrs |
| Materials cost | $13,950–$21,775 | $275–$450 |
| Footing depth | 36″ × 6 posts | 36″ × 2 posts |
| Concrete | 12 × 60-lb bags | 4 × 60-lb bags |
| Cut-list items | 7 | 5 |
| Build steps | 12 | 9 |
Cost & budget
The 12x16 ft Hot Tub Pavilion Plan lands in the $13,950–$21,775 range for materials in Black Locust, while the 3x4 ft Pergola Archway Arbor Plan runs $275–$450 in Black Locust. The second plan is approximately 4879% more expensive at typical 2026 lumber-yard pricing — driven mostly by the choice of Black Locust over Black Locust and the difference in cubic concrete volume between 6 and 2 footings.
Labor & difficulty
At ~138 hours, the 12x16 ft Hot Tub Pavilion Plan is rated Advanced. The 3x4 ft Pergola Archway Arbor Plan takes ~33 hours and is rated Intermediate. The labor delta is roughly 105 hours, or one extra working day on the 12x16 ft Hot Tub Pavilion Plan. If you are newer to outdoor woodworking, the 3x4 ft Pergola Archway Arbor Plan is the safer pick — it uses simpler joinery and fewer compound cuts.
Footprint & site fit
At 192 sq ft vs 12 sq ft, you are choosing between a generous patio cover and a focal-point garden structure. Allow at least 24 inches of clearance on every side for furniture and walking paths — that means the 12x16 ft Hot Tub Pavilion Plan needs a clear area of approximately 16×20 ft and the 3x4 ft Pergola Archway Arbor Plan needs 7×8 ft.
Material & durability
The 12x16 ft Hot Tub Pavilion Plan is built from Black Locust, while the 3x4 ft Pergola Archway Arbor Plan calls for Black Locust. Both plans share the same species, so you can buy from a single lumber order if you build them in sequence — a common move for homeowners adding both a primary structure and a complementary screen or arbor.
Verdict
For a builder weighing these two specifically, 3x4 ft Pergola Archway Arbor Plan is the clear budget pick. If both fit your budget and yard, default to the design whose style language matches the rest of your house — a Craftsman bungalow looks awkward beside a modern slatted pergola, and vice versa.
Read each plan in full before committing: the complete 12x16 ft Hot Tub Pavilion Plan page and the complete 3x4 ft Pergola Archway Arbor Plan page. Both ship with full cut lists, hardware schedules, footing specs, and step-by-step build instructions.