Guide for architects, modellers and energy consultants

IFC import: from the building model to a reliable cost estimate.

Renaldo reads rooms, apartments, façade, roof, windows and doors straight from your IFC model and turns them into quantities and costs. Whether that works is decided while modelling – not at export. This guide says what matters and shows it per tool for Archicad and Revit.

Download the reference file (IFC) Archicad & Revit
IFC 2x3 Coordination View 2.0 or IFC4 · rooms and base quantities enabled · English and German room names
Why it matters

Three sentences that make the difference.

Room names are the foundation

Renaldo derives the room type from the name. "Bathroom" becomes a bathroom with tiles, sanitary fit-out and extract air – "R-102" becomes living space, and the entire bathroom fit-out is missing from the estimate.

Apartments must be grouped

Without an apartment assignment Renaldo assumes one dwelling unit. An apartment building is then costed like a single-family house – apartment entrance doors, meters and bathrooms per apartment are lost.

The import reports no warnings

Discarded openings, skipped walls and unrecognised rooms happen silently. That is why there is a control image: it shows what Renaldo read before you import.

What Renaldo reads from the model

Six things – and where they come from.

Everything else in the model can be anything. These six points decide whether the estimate is right.

Renaldo needsIn the IFCWhat counts
Rooms with a room typeIfcSpace with Name/LongNameMeaningful names from the word list – Bathroom, Kitchen, Bedroom, Corridor, Storage; German Bad, Küche, Schlafzimmer, Flur, Abstellraum. No numbers, no abbreviations.
ApartmentsApartment code in name or number, parent space or IfcZoneSimplest: WE01-01, WE01-02 … as the room number. Renaldo builds the dwelling units from it.
Room quantitiesQto_SpaceBaseQuantitiesEnable base quantities at export: area, perimeter, height, wall areas per room.
FaçadeIfcWall with Pset_WallCommon.IsExternalMark exterior walls as external, gable walls included. Renaldo measures the façade area from geometry – also for gables exported as a rectangular wall clipped by the roof.
Windows and doorsIfcWindow/IfcDoor with OverallWidth/OverallHeightPlaced in the wall; Renaldo assigns them to rooms by position. The entrance door carries -AT- or "Entrance" in its name – otherwise it counts as an interior door.
RoofIfcRoof, one covering surface per pitchRenaldo reads eaves, ridge, verge and eaves height from geometry. Two roof surfaces = gable, four = hip, one = mono-pitch – or pick the roof form in the preview.

Balconies as slabs with "Balcony" or "Balkon" in the name. What is not in the model comes as a short list: building perimeter, number of stairwells, basement perimeter and height, apartment entrance doors, roof windows, dormers, balcony railing lengths.

Per tool

The same six points – in your BIM software.

The import is the same for every program. What differs is only where you set the six points. One page per tool that maps every requirement to the concrete feature.

Graphisoft

Archicad → Renaldo

Zones as rooms (Name = room type, Number = apartment code), wall position Exterior, element ID for entrance door and balcony, translator with base quantities, one roof per pitch. Including the modelling order when working from a point cloud.

Archicad workflow →
Autodesk

Revit → Renaldo

Export rooms in 3D views, enable base quantities, wall function Exterior, room number as apartment code, entrance door via type name or IfcName, one roof per pitch. With the matching export setup.

Revit workflow →

Allplan, Vectorworks or another tool? The six points apply unchanged; send us a first export, we run it through our importer and reply with the concrete findings.

Reference file and control image

Mirror first, then check.

The reference file

A complete apartment building with basement, three apartments, gable roof, gable walls, overhang and balcony – every rule of this guide is applied in it. Open it in your program and mirror its structure.

Reference file (IFC, 150 KB)

The control image

On import, Renaldo shows the model in 3D as it was read: rooms green when the room type is recognised, red when not; windows blue, doors brown, the entrance door orange. Cut per storey, hide roof and façade, tap elements. Red rooms can be corrected right before importing.

Open the guide in the app
New design stages

Export again, import again – without losing anything.

An IFC is a snapshot of the design stage. When the design changes, simply import the new file. Renaldo does not ask what to keep – it follows one fixed rule:

  • The new model defines the geometry – areas, perimeters, windows, doors and apartment assignment always come from the new file.
  • Recognised rooms keep their identity – photos, defects, inspection checkpoints and all settings are preserved. Recognition uses the GlobalId, otherwise storey and name.
  • Rooms missing from the new model are dropped – the preview shows beforehand which ones, and what is attached to them.

What matters for this: keep working in the same model file so the GlobalIds stay stable, and do not rename rooms without reason.

FAQ

Frequently asked questions about the IFC import.

IFC 2x3 Coordination View 2.0 with rooms (spaces) and base quantities enabled. IFC4 Reference View works as well. Millimetres or metres are both fine.
Renaldo derives the room type solely from the room name. Numbers or abbreviations such as "R-102" give no type; meaningful names such as Bathroom, Kitchen, Bad or Küche are recognised – in English and German. In the control image such rooms appear red and can be corrected before importing.
Via an apartment code in the room name or number (WE01-01, WE01-02 …), or via a parent space or IfcZone per apartment. Without grouping Renaldo assumes a single dwelling unit.
No. Façade areas come from the exterior walls; eaves, ridge, verge and eaves height from the roof geometry. What is not in the model – building perimeter, stairwells, basement perimeter – you supply as a short list.
Export again and re-import. The new model defines the geometry; recognised rooms keep their identity, photos, defects and your settings. The preview shows how many rooms were updated, added or dropped.
Yes. Any program with an IFC export that writes spaces and base quantities works – the six points above apply unchanged. Send us a first export, we check it and reply with the concrete findings.

Upload the model, read the control image, calculate.

The IFC import is part of Renaldo Expert, Developer and Contractor. Start free, import a first model, see immediately what was read.

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