Best Deck Design Software in 2026: 7 Programs Compared

What to Look for in Deck Design Software

A deck looks simple on paper: a rectangle of boards next to the house. In practice, the height of the door threshold, the slope of the yard, the stairs down to the garden and the railing rules decide whether the design works. These are the points that matter when you compare tools:

• Connection to the house: the deck surface has to line up with the door, and windows, roof overhangs and downspouts affect where it can go.
• Terrain: on a sloped lot, one side of the deck may sit almost on the ground while the other is several feet up. The tool should show the real ground.
• Railings and stairs: in areas that follow the International Residential Code, a guard is generally required where the deck surface is more than 30 inches (about 76 cm) above the ground, with a minimum height of 36 inches (about 91 cm) and openings that do not let a 4-inch (about 10 cm) sphere pass. Check the rules with your local building department.
• Structure: posts, beams, joists and footings should be part of the model, so your builder sees how the deck is carried.
• Exact dimensions: a typical family deck of 12 by 16 feet (about 3.7 by 4.9 m) leaves room for a table and a grill. You need exact sizes to compare layouts. Our guide How Big Should a Deck Be? helps you choose the right size.
• Drawings for the permit: many building departments want a plan and a section of the deck before you build.

Deck Configurators vs. Planning the Deck with the House

The free deck designers from decking brands and home centers are configurators: you choose a shape, a height, boards and railings, and you get a picture and a shopping list. A full design program plans the deck as part of the building and the lot. The difference shows as soon as the deck is raised, the yard is sloped or the deck gets a roof:

1. Plan7Architect: Best Overall Deck Design Software for Decks Attached to Your House

Price: $259.99 Original price was: $259.99.$169.99Current price is: $169.99. one-time purchase, lifetime license, no subscription
Platform: Windows desktop software
Best for: homeowners, self-builders, carpenters and contractors who want to plan the deck with the house, the terrain and the garden

Plan7Architect is a complete house planning program with deck, terrace, balcony and railing tools. You draw the house or rebuild your existing one with real walls, doors and windows, then add the deck exactly where it belongs. Every change in the 2D plan updates the 3D model, the sections and the elevations at the same time.

Decks, Railings and Stairs

You plan ground-level decks, raised decks, wraparound decks, terraces and balconies with exact dimensions, entered in feet and inches or in meters. Railings can be designed in wood, metal, glass or mixed materials, with adjustable height and baluster spacing, so you can follow the rules that apply where you live. Stairs lead down to the garden on the real terrain. Our guide Planning a Railing Yourself shows the railing tools step by step.

Posts, Beams and Foundations

With the timber construction tools and custom beam structures you model the structure under the deck: posts, beams and joists in the sizes you choose. Foundations are planned in the same project, and you can see the whole structure in 3D and in the sections. For a covered deck or a porch, the roof is constructed automatically, with gable, hip, shed and flat roofs available.

Deck on a Sloped Lot

Terrain modeling with contour lines and sloped lots shows the real ground under your deck. You see how high each post has to be, where stairs need more steps and how the deck connects to the patio, the lawn and the paths around it. Garden objects, plants, outdoor furniture and lighting from the extensive library complete the picture, and you can import more models from the SketchUp 3D Warehouse.

All deck-related tools at a glance:

• Decks, terraces, balconies, railings and garden objects
• Stairs and unlimited floors and buildings in one project
• Timber construction tools and custom beam structures
• Foundation planning
• Terrain modeling with contour lines and sloped lots
• Automatic roof construction for covered decks and porches
• Automatic dimensioning and exact entry of lengths, angles and distances
• Electrical planning for deck lights and outdoor outlets
• Every element can be customized, saved to the catalog and reused

Drawings for the Building Permit

From the same model you create floor plans, sections and elevations of the house and the deck, assemble plan sheets with title blocks, print them to scale, save them as PDF or export them as DWG/DXF for your engineer or contractor. You can walk through the design in 3D, and for photorealistic images and videos, you export it to Twinmotion with all textures.

Pricing

Plan7Architect Pro costs $259.99 Original price was: $259.99.$169.99Current price is: $169.99. once and can be activated on up to 3 PCs. Chief Architect Premier costs $1,995 every year, and SketchUp Pro with LayOut costs $399 every year, so after one year either one costs more than twice the price of Plan7Architect.

2. Trex Deck Designer: Best Free Deck Design Tool

Price: free, Deck Designer account required
Platform: desktop browser (Edge, Chrome or Safari), not designed for phones
Best for: homeowners planning a composite deck with Trex products

The Trex Deck Designer is a free 3D tool for square and rectangular decks, including multi-level and second-story decks. It creates a materials list, shows estimated costs with and without labor, lets you choose joist sizes and wood types for the substructure and generates a blueprint you can share with a contractor or your local planning office.

It focuses on the deck itself rather than on the house and the lot around it, and it is built around the Trex product range.

3. TimberTech Deck Designer: Best Free Tool for Comparing Railing Styles

Price: free, sign-up required
Platform: desktop browser and tablets with screens of 8 inches or larger
Best for: homeowners comparing TimberTech decking and railing options

The TimberTech Deck Designer lets you test size, shape, stairs and style, compare railing styles side by side and download an itemized list of boards, fasteners, railing sections and accessories for a dealer quote.

TimberTech itself says the layouts and dimensions are for reference and should be reviewed by a licensed professional before building. The tool focuses on the deck and on TimberTech products.

4. Lowe’s Deck Designer: Best Free Planner for a Home Center Shopping List

Price: free
Platform: Windows or Mac desktop or laptop, minimum screen resolution 1920 by 1080
Best for: do-it-yourselfers who buy the materials at Lowe’s

Lowe’s Deck Designer starts from inspiration, sample templates or your own drawing. It includes pressure-treated and composite boards, railings and patio furniture, and the downloadable project contains a 3D rendering, building plans, a materials list and a cost estimate.

The cost estimate is basic, and like the brand configurators, the tool focuses on the deck itself rather than on your house and lot.

5. Realtime Landscaping Architect: Best for Decks as Part of a Landscape Design

Price: $599 one-time purchase (Realtime Landscaping Pro with the same deck tools: $279)
Platform: Windows
Best for: homeowners and landscape designers who design the deck together with the yard

Realtime Landscaping has a deck wizard and a freeform deck tool with multi-story decks, curved decking and railings, hot tub cutouts and more than 140 wood materials. Terrain tools, pools and a large plant library put the deck into a complete outdoor design, and it is sold without a subscription.

Houses are modeled as exteriors only, so the interior, floor plans of the house and sections for a permit are not part of the program.

6. SketchUp: Best for Modeling Custom Deck Details

Price: free web version for personal use; Go $129 per year; Pro $399 per year
Platform: browser; Pro also on Windows and Mac
Best for: woodworkers and builders who want to model every board and connection

SketchUp gives you complete freedom: you can model each joist, post and board, and many deck builders use it for custom details. The 3D Warehouse offers ready-made components.

Everything is drawn by hand. Railings, stairs and framing need modeling work or plugins, and dimensioned plan sheets require LayOut in the paid desktop plans. See our SketchUp alternatives comparison.

7. Chief Architect Premier: Professional Software for Builders and Designers

Price: $1,995 per year or $229 per month
Platform: Windows and Mac
Best for: professional residential designers and builders who draw construction documents every day

Chief Architect Premier creates deck planking and deck framing automatically and lets you edit the framing manually. Decks are part of the full house model with construction documents, so it is a strong tool for professionals.

For a private deck project, the subscription is hard to justify, and the program takes time to learn. If you are comparing both, read our Chief Architect alternatives page.

How to Choose the Right Deck Design Software

• You want a quick layout and a shopping list for one brand: Trex Deck Designer or TimberTech Deck Designer, both free.
• You buy your lumber at a home center: Lowe’s Deck Designer.
• You plan a deck on a sloped lot, a raised or covered deck, or a deck for a new house: Plan7Architect, because house, terrain and deck are in one model.
• You design a complete backyard with pool and plants: Realtime Landscaping Architect.
• You are a professional designer with daily construction documents: Chief Architect Premier, if the subscription fits your budget.

Plan Your Deck with Plan7Architect

With Plan7Architect you design your deck where it really belongs: on your house, on your lot, with railings, stairs, posts, beams and foundations, and with the drawings your building department and your builder need. No CAD experience is required, there is no subscription, and our video tutorials show every step. Every purchase comes with a 14-day right of withdrawal: if the software is not what you expected, you can simply cancel your purchase by email, so you can plan your own deck without risk.