Structural software for homes and mid-rise buildings, with the building model behind it.

The structural model comes from the architectural one

In traditional structural software the model is built from scratch. The building is redrawn as nodes and lines, and its geometry is simplified until the solver can read it. Nothing in that software frames a wall, an opening, a roof or a floor, so the framing is drawn somewhere else again.

In PerCode AEC the structural model is derived from the architectural model. 3-D elements that touch are connected, and those connections are the load path. Walls, roofs and floors are framed from what you drew. The wind, seismic, snow and gravity loads are applied from the model and the site, once you have answered the questions the code leaves to the engineer.

Around the model: schedules, an extensive product catalog you can add to, PDF and DXF underlays in, and DXF, PDF, IFC and shareable 3-D links out — and the complete design report, ready to stamp.

One model, two modes, two views

Most building jobs are drawn in one program, calculated in another, and checked with a spreadsheet, and the three drift apart with every revision. PerCode AEC keeps one model. The drawing is the model, and the analysis is read from it at the moment you run it, so there is no second model to keep in step by hand.

Architectural mode is where a model starts: walls, doors and windows, roofs, decks, slabs and depressions, drawn over a PDF or DXF underlay with levels and reference lines taken from the drawing. Structural mode adds the framing, the supports, the loads and the design run. Every element sits on a level with an offset, so a wall, a roof or a slab is placed the way the drawings dimension it.

Every structural element has a physical view — the member as it will be built, with its real size and position — and an analytical view, the wire model the solver reads. Both are cuts through the same 3-D model, so they cannot disagree.

What it models

• Walls framed stud by stud — studs, king and jamb studs, cripples, sills, headers and top and bottom plates — with the openings you drew, sheathing, and joins between walls that touch.
• Roofs generated from the plan outline: hips, valleys and gables, including a roof that is hipped at one end and gabled at the other.
• Trusses laid out along the roof, either as lines that carry load to their bearings or as trusses with real member sections that are designed.
• Floor and roof decks, beams, columns, posts, in-line studs and multi-ply members.
• Foundations — wall footings, spread footings, mono slabs and stem-wall foundations, slab depressions.
• Connections — Simpson Strong-Tie hold-downs, straps and ties from the current catalog, and bolt, nail and screw groups.
• A product catalog you can extend — connectors, sheathing and deck panels, steel, cold-formed and engineered-wood sections. Add a product in the Catalog Manager, and each project keeps a short list of the products it uses.
• Releases and links where a joint does not carry moment or two parts of the model meet.

What it designs, and to which clauses

A design run analyses the whole building once and checks every element from that one analysis. Each check in the report names its standard and clause. The material decides the standard:

Wall studs, headers and plates are designed as members, not looked up: a header that fails moves up its size list until it passes, and the report says which size it settled on and why.

Loads you can follow

The load wizard reads the building from the model and the site from the project, asks the engineer the questions the code leaves to judgement, and writes each hazard as a full calculation — the same report the stand-alone load modules produce — to ASCE 7-16 or ASCE 7-22.

The site hazards — wind speed, snow and seismic values, and flood zone — are read for the project address from the ASCE Hazard Tool and FEMA's flood maps, and stay with the project.

• Wind — main wind-force resisting system pressures on walls and roofs, and components and cladding on the roof zones, with effective areas per §26.2.
• Snow — ground, flat-roof and sloped-roof snow with the site's climate zone.
• Seismic — the seismic response coefficient from Chapter 12, distributed per §12.8.3 from the model's own mass, as ±X and ±Y patterns or eight under the §12.5 orthogonal combination. A structure exempt under §11.7 gets no seismic patterns at all.
• Gravity — live loads from the occupancy short list of Table 4.3-1, and dead loads from the assemblies you build.
• Combinations per ASCE 7 §2.3 (LRFD) and §2.4 (ASD), each material read on its own basis.

If the building or the site changes after a hazard was calculated, the design run refuses until the calculation is brought up to date, and one button recalculates it with the answers you gave the first time.

The analysis

A three-dimensional frame solved by the direct stiffness method, six degrees of freedom per node, linear and static. Members are meshed where they meet, releases are honoured, and a model that cannot carry its load stops the run instead of returning numbers.

Serviceability is checked from the same solution: member deflection against IBC Table 1604.3 or IRC Table R301.7, wind drift against your limit, and seismic drift amplified by C_d/I_e (§12.8.6) against Table 12.12-1.

What you hand in

• A PDF report with the sections you choose: loads, the analysis, every element's checks with their clauses, key plans and load tags.
• Drawings exported to DXF and PDF, from the canvas or as sheets.
• Schedules of connectors, wall openings (rough openings, kings, jacks, headers and sills) and posts.
• A 3-D link to the view on your screen, for anyone with a browser (paid plans; each link lasts seven days).
• An IFC4 file of the model for the architect's or contractor's BIM tool.
• Project files that keep their history: every save keeps a version, and the project manager knows which reports are out of date.

Code basis

Every account practises in one state, chosen at signup, and that state's adopted codes set the basis in every module — Florida runs the FBC 2023 today and the FBC 2026 ahead of its December 31, 2026 effective date. A national model-code basis (IBC with ASCE 7, no state) is open to every account.

What it will not do

An engineer should know the edges of a tool before relying on it. These are PerCode AEC's:

• It does not run second-order (P-delta) analysis or include shear deformation; the analysis is linear and static.
• It does not check member bearing (NDS §3.10) or cold-formed steel web crippling.
• It does not design truss plates, or trusses drawn as load lines; those are for the truss manufacturer's engineer.
• It does not design basements or the slab on grade itself; it designs the footings and thickened edges under it.
• Wood is designed by ASD only.
• Floor and roof panels are checked for gravity loads only.
• The IFC export places the whole model on one storey.
• It does not design one truss at a time; it designs the building.
• It does not stamp anything. The engineer of record reviews and signs; the software never does.

Which plan includes it

The free trial opens every mode. See pricing