Design
Edit design specs then click Apply.
Most units are inches.
IRC Code
IRC Building Code Compliance
(Affects automatic header design)
Year
Exposure
Wind Speed
Ground Snow Load
Enclosure
Walls
Stud OnCenter
Stud Material
Bottom Plate Material
Bottom Plate Material Max Len
Top Plate Material
Top Plate Quantity
Top Plate Material Max Len
Top Plate Min Stagger
Sheathing
Material
Orientation
Stagger Bays
Adjust Top NonGable
Adjust Top Gable
Adjust Bottom
Roof
Roof Type
Slope (degrees)
Eave Projection
Birdsmouth Seat Depth
Rafter Material
Rafter OnCenter
Rafter Tail Max Plumb Height
SubFascia Material
SubFascia Max Plumb Height
SubFascia Material Max Len
SubFascia Splice On
SubFascia Corner Style
SubFascia Drop
Fly Rafter Material
Fly Rafter Max Plumb Height
Fly Rafter Material Max Len
Lookout Material
Lookout Orientation
Gable Top Plate Material
Gable Bottom Plate Material
Gable Stud Material
Rafter Tie Material
Collar Tie Material
Collar Tie Drop
Hip Rafter Material
Hip Rafter Plys
Hip Rafter Drop
Align Rafters with Studs
Ridge Beam Material
Ridge Beam Plys
Ridge Beam Drop
Ridge Post Material
Decking Material
Floor
Floor Type
Decking Material
Joist Material
Joist Max Span
Joist OnCenter
Joist Orientation
Decking Stagger Bays
Rim Material
Rim Material Max Len
Foundation
Foundation Type
Material
Mudsill Material
Mudsill Material Max Len
Slab Height
Slab Position
Wall Height
Wall Thickness
Footing Height
Footing Width
Footing Depth
Girder Material
Girder Plys
Girder Pocket Bearing
Girder Pocket Gap
Girder Max Span
Girder Ply Max Len
Pier Diameter
Pier Height
Pier Depth
Pier Material
Post Material
Girder Material
Girder Max Span Exterior
Girder Max Span Interior
Girder Plys
Girder Ply Max Len
Joist Over Girder Cantilever
Girder Over Pier Cantilever
Bracket Length
Bracket Standoff
Bracket Part
Pier Diameter
Pier Height
Pier Depth
Pier Material
Openings
Declare opening placements below.
Door/Window Model
Wall
Xā
Zā
Headers
Materials
Edit available materials.
Doors and Windows
Door/Window Model
Width
Height
Cost
Board Lumber
Name
Class
Thick
Width
Length
Cost
Sheet Lumber
Name
Thick
Width
Wgap
Length
Lgap
Cost
Concrete
Connectors
BuildFreely is a CAD tool for generating a building model, plans, bill of materials, and cost estimate from your parameters and materials lists.
It does not use AI. All code was written manually.
Currently, it can generate only single story, rectangular structures with either a shed, gable, or hip roof.
It is possible to generate designs which are unsafe and do not adhere to proper building codes. Review design with a engineer before building.
Thu Oct 8 06:08:33 UTC 2026
- Improves error messages, especially in regards to overlapping framing of openings. Such overlaps will appear colored red.
- User can now select IRC code to utilize for automatic header design.
- Gives user ability to construct custom header and opening design.
Fri Aug 21 04:04:57 UTC 2026
- Better phone support.
Wed Aug 19 00:30:57 UTC 2026
- Improves part edges in 3D client.
- Adds hip roof support (still a work in progress).
Tue Aug 4 21:09:33 UTC 2026
- Concrete foundations can now be generated with central girders to support long floor joists.
Fri Jun 19 16:50:54 UTC 2026
- Gable roof design now generates lookouts.
- Rafter tail max plumb height now working for gable roofs.
- Fascia and fly rafter max plumb heights can now be specified.
- Improved console messages when rendering.
Tue Jun 9 20:25:29 UTC 2026
- Windows can now be stacked above each other.
Fri May 29 22:10:16 UTC 2026
- Fixes bug in common stud placement and crippling when overlapping opening.
Fri May 29 04:42:13 UTC 2026
- Add support for ridge beam posts in gable wall.
- Improved BOM part grouping, so parts of similar shape are more likely to appear together in same part cut plan.
- Shed roof now support walls with flat top plate and birdsmouth cut in rafters (instead of top plates sloped to match rafter angle).
- Gable roofs now include optional collar ties. Ceiling joists renamed to rafter ties.
- Sheathing now covers gable walls of gable roof.
Sun May 24 22:24:56 UTC 2026
- Bug fixed regarding loading new design over current one, was resulting in messed up openings.
Sun May 24 00:02:38 UTC 2026
- Opening X values now describe position of center of opening (previously was left edge of opening for non-percentage values).
- Opening Z values can now be negative to express distance from top of wall to top of opening.
- Maximum height above grade of structure is now reported (see top left corner of screen).
Wed May 20 17:08:19 UTC 2026
- Enclosure dimensions now describe dimensions of exterior of framing (previously included sheathing).
- Sheathing no longer laps sheathing of adjacent wall. (might add this back as an option later, would be nice especially for thicking sheating that includes insulation layer).
- Better layout of sheathing and roof decking to ensure edges of wall and roof begin with large panel for greater strength.
- Sheathing is now optional
Sun May 3 01:39:30 UTC 2026
- Adds fancy incremental reveal of parts for initial load of 3D model.
Sat Jan 3 02:16:14 AM UTC 2026
- Simplifies gable end wall, no longer employs top and bottom plates in triangular portion of wall.
- New code for sheath staggering
Tue Dec 9 05:03:49 AM UTC 2025
- Adds "skid" foundation type (aka girder only).
- Fixes pier foundation bugs regarding cantilever, and now allows negative cantilever.
- Fixes some lookout and subFascia bugs.
Fri Dec 5 07:08:39 AM UTC 2025
- Fixes interference of top plates of adjacent walls.
- Fixes errors in shed roof top plates where plates were generated too thin.
- Adds foundation mudsill material max length specification so long mudsill boards will be split to smaller size.
- Reduces mouse control zoom and rotate rate for more precise control.
Wed Jan 29 07:53:13 PM UTC 2025
- Better BOM scaling, and dimension label positioning.
Sat Jan 25 03:46:52 AM UTC 2025
- Adds concrete foundation type.
- X Positioning of opening supports mutliples and percents.