IFC Accessibility Check

Pathfinder-driven accessible-route audit. Builds a navmesh from your IFC and reports spaces that can't reach a tagged accessible entrance without stairs, corridors below the configured width along the route, ramps steeper than 1:12, and door-threshold heights above the code limit. Routes overlay on the model and export to BCF.

Check an IFC model's accessible routes online. Upload the model, tag the accessible entrances, and get back every space that can't reach one — plus the corridors too narrow, the ramps too steep, and the doors too tight to be part of an accessible route.

Accessibility is checked by walking a plan with a scale rule, which is slow, and by reviewers who know the regulation but can't hold the whole building in their head, which is unreliable. The model already knows the geometry. This runs a real pathfinder over it against ADA, IBC and UK Approved Document M defaults, all of which you can override for your own jurisdiction.

When to reach for it: During DD or before tender to confirm every occupiable space has a stair-free, code-width route to an accessible entrance. Catches narrow corridors / steep ramps / non-compliant door clear widths that pure pset checks miss.

What you get: A unified findings sidecar listed in the Validate tab (with chips for unreachable / narrow-corridor / ramp-slope / threshold counts), a BCF export with one topic per check section, an HTML report, and route polylines you can overlay on the 3D viewer to see exactly where the path fails.

Example: Run during DD to confirm every occupiable space has a wheelchair-reachable route to an accessible entrance.

Six checks over a real route graph

The check builds a navigable graph from the model's spaces and openings and pathfinds across it, rather than measuring distances in straight lines. That's what makes the answers meaningful: a space thirty metres from an entrance in plan may be a hundred metres of actual route away, or unreachable entirely.

Unreachable spaces — every IfcSpace must reach a tagged accessible entrance. The pathfinder runs with stairs disallowed, so a route that depends on a staircase counts as no accessible route at all.
Corridor width — the narrowest sampled width along the route is checked against your minimum. The narrowest point governs, because a route is only as accessible as its tightest pinch.
Stair-only routes — flagged SEPARATELY when a non-accessible route exists but an accessible one doesn't. That distinction is the useful one: "there is no way to get here" and "there is a way but it uses stairs" are different design problems with different fixes.
Ramp slope — every IfcRamp portal against your maximum, defaulting to 4.76°, which is 1:12.
Door width — every tagged accessible entrance against your minimum clear width.
Threshold height — read from the door's common property set where the model records it.

Missing data is treated as compliant — and why you need to know

Threshold height is checked only where the model actually records it. Where it doesn't, the door is treated as compliant rather than flagged. That's the right default — flagging every door in a model that never exported threshold data would produce a report of hundreds of findings, none of them evidence of anything, and the real findings would be lost in it.

But it means a clean result on this check is not proof of compliance; it is the absence of detected non-compliance in the data present. Run the Data Completeness Check to see whether the model carries door property data at all, and use the IDS Checker to REQUIRE the properties this check reads — that converts an assumption into a validated condition you can re-run on every revision.

Regulation defaults, and your own numbers

The presets encode common thresholds from ADA, IBC and Approved Document M, which is a starting point rather than a legal position — jurisdictions differ, projects have their own standards, and a client brief can be tighter than any code. Every threshold is editable: minimum corridor width, minimum door width, maximum ramp slope, and whether a stair-free route to the entrance is required at all.

Findings export as HTML, CSV or BCF, so a route problem can be issued as an item against the model rather than described in a meeting, and each finding isolates its space in the 3D view so a reviewer sees the actual geometry. Pair it with the Fire Egress Check, which shares the same route engine and covers escape rather than access — the two together are the life-safety pass over a model.

How to check accessibility in an IFC model

Upload your IFC file (the tool needs slabs, walls, doors, spaces, and stairs for the navmesh)
Pick a code preset — ADA 2010, IBC 2021, UK Approved Doc M, or strict power-chair
Override individual thresholds if the project deviates from the preset (corridor width, door width, ramp slope, threshold height)
Tag accessible entrances / accessible stairs / storey scope if the auto-detect from Pset_DoorCommon / Pset_StairCommon needs correcting
Click Run — the engine tessellates the model, builds a per-storey navmesh, and pathfinds from every IfcSpace
Review findings in the FindingsList panel; click 'Show route' on any finding to overlay the polyline on the model
Send the findings to BCF or to your project Issues room

Under the hood

BIMCamel parses IFC files in the browser using the open-source web-ifc engine and renders models with @thatopen/components + three.js. Heavy operations (clean / optimise / validate / convert) run on disposable server-side workers using the same web-ifc stack plus our own .NET pipeline; results stream back to your browser as soon as they're ready. Uploads sit on our servers only as long as your tier's retention window allows and are never used to train AI.

Frequently asked questions

Is there a free ADA compliance checker for BIM models?

This page. Upload the IFC, tag the accessible entrances, and it pathfinds every space to an entrance and checks corridor widths, ramp slopes, door widths and thresholds against ADA, IBC and UK Approved Document M defaults — all editable for your jurisdiction.

Does it account for stairs?

Yes, and carefully. The accessible-route pathfinder disallows stairs, so a stair-only route counts as unreachable — and those spaces are reported separately from spaces with no route at all, because "no way to get here" and "a way that uses stairs" are different problems.

How is corridor width measured?

The route is sampled along its length and the NARROWEST point governs, because a route is only as accessible as its tightest pinch. A corridor that widens after a pinch point is still blocked at the pinch.

What if my model has no door threshold data?

Doors without recorded threshold heights are treated as compliant rather than flagged — otherwise a model that never exported the property would produce hundreds of findings that are evidence of nothing. It also means a clean result isn't proof of compliance. Use the Data Completeness Check and the IDS Checker to make sure the data is there.

Can I use my own thresholds?

Yes — minimum corridor width, minimum door width, maximum ramp slope (default 4.76°, or 1:12) and whether a stair-free route to the entrance is required are all editable. The presets are a starting point, not a legal position.

What's the maximum IFC file size?

Up to 25 MB as a guest, 100 MB with a free account, 500 MB on Pro, and 1 GB on Team. The caps are on upload size only — every tool itself is available on every tier.

What happens to my file after processing?

Your file is uploaded over HTTPS and processed on our servers. Guest uploads are stream-only — the working files are deleted as soon as your download finishes. Free accounts keep results for 7 days; Pro keeps them 90 days and Team 180 days. Files are never shared with third parties or used to train AI.

Is IFC Accessibility Check free?

Yes. IFC Accessibility Check is free to use — guests get 3 runs a day with 25 MB uploads, and a free account raises that to 10 runs a day with 100 MB uploads. No trial clock, no watermarks.