Compliance checks — MEP Tools

Every coordination check the tool runs, grouped by family, with what triggers it.

The Validation panel lists every issue the current layout has, split into Violations (must fix) and Warnings (worth a look). Each issue card can expand to show Where, Why, and — for some issues — a one-click Fix.

The checks fall into five families:

Zone boundaries

• A zone reaching past the sides of the void, up into the Structural Beam Band, or down into the Ceiling Device Drops Band is flagged — that space doesn't exist for anything placed inside it.
• A duct, tray, or pipe that has drifted outside its own zone is flagged.
• A standard duct sitting over Zone A's width is flagged — only a Low Condensation Risk Duct may pass over the electrical zone.

The access corridor (Zone B)

• Zone B narrower than the Zone B minimum width threshold is flagged as too narrow to work in; at exactly the minimum it's a warning instead.
• Zone B not sharing an edge with Zone A is flagged — the trays become unreachable.
• A cable tray further than the Arm's reach limit from the nearest Zone B edge is flagged.
• A tray or pipe crossing Zone B is a warning — a crossing is sometimes unavoidable, but it should be a deliberate, agreed position rather than an accident of routing.

See Zones & bands for what each zone is for, and Rule set for the exact threshold values and how to adjust them per project.

Clearances

• Two services occupying the same space is a collision.
• A pipe running directly above a cable tray is flagged — pipework leaks and sweats, and water is kept beside or below power, never above it.
• Two services of the same family closer than the project's clearance are flagged; an ELV/signal tray closer than the ELV / non-ELV separation threshold to a power tray gets its own message calling out the interference risk.
• A main sitting closer than the Clearance above dry tray threshold above a cable tray is flagged — cable is loaded into a tray from above, and needs headroom to keep being loaded over the life of the building.

Branch routing

• A branch whose take-off, runs, and termination don't join up into a drawable route is flagged, naming the specific problem.
• A branch that crosses another service family on its way to its outlet is flagged.
• A cable tray branch taking off from the top or bottom face is flagged — cable only leaves a tray over its side wall.
• A branch that crosses back over its own parent service, or doubles back on itself with no horizontal travel, is flagged — neither can be built from real fittings.
• A side take-off that doesn't leave level with its parent's centreline, or a run/bend that overlaps the parent's body, the void's walls, or the slab/ceiling boundary, is flagged.
• Bends ordered so the route reverses direction partway through are flagged.
• A branch ending at the slab or ceiling with no end position set, or an end position outside the void, is flagged.
• A branch ending at the slab is also given a warning to confirm the opening with the structural engineer — this is a check, not an error.

See Branches & take-offs for take-off sides, terminations, and how the panel keeps edits legal.

Document integrity

If any field the other checks compare against isn't a real number — from a hand-edited or imported file — it's flagged by name (for example zones.zoneB.w) before any other check runs. This exists because a comparison against a non-numeric value never fails on its own, so without this check a broken document could otherwise read as fully compliant.

Fixing an issue

Click Zoom to it on an issue card to jump the canvas to the offending element. Where a Fix button is offered, it applies the repair directly; otherwise, follow the Why text and adjust the element from its own inspector panel.