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Room area in Revit, colour fill plans and area plans

Room area in Revit depends on four wall references you set once for the project. Place rooms, tag them, colour them by name, then build an area plan.

  • Dr. Nguyen Manh Tuan
  • 14 min read
A floor plan coloured by room name, with the legend generated from the scheme Photo: Screenshot taken on Revit 2027 at the Institute

Room area in Revit is never a figure you type in. Place rooms properly and the name, number, area, volume and colour all read from one source, so moving a wall updates all five at once.

This article runs from the first room placed through to a coloured plan and an area plan. To learn modelling and documentation end to end, see the Revit Architecture course.

What a room is, and why you cannot see it

A room is a volume of space bounded by elements that are room-bounding. It has no material, no quantity, and prints no line at all.

Three things people mix up Photo: A room, a room tag and an area are three different objects

Think of a room as an invisible box. It measures its own floor area, perimeter and volume, and carries a name and a number you give it. Autodesk describes the mechanism on About Rooms.

Any element that can stop a room carries a Room Bounding parameter in its Properties. Walls, floors, ceilings, columns, roofs and curtain walls all have it, and all have it switched on. That is why the walls come first and the rooms second.

From walls to a coloured plan Photo: Six steps from settling the measuring rule to a finished coloured plan

Create a room in Revit, and the room separator

Every tool for this job sits on one panel of the Architecture tab.

The Room and Area panel Photo: The Room & Area panel with its six tools, three of them greyed
ToolWhat it is for
RoomPlaces a room. Only active in floor plans and ceiling plans
Room SeparatorDraws a dividing line where there is no wall
Tag RoomTags a room that already exists
AreaPlaces an area object, or creates a new area plan
Area BoundaryDraws an area boundary. Only active in an area plan
Tag AreaTags an area object

The three tools on the left work with rooms, the three on the right with areas. They belong to different view types, so three are always live and three always greyed.

Start the Room tool and the ribbon switches to a contextual tab worth knowing.

The ribbon while placing rooms Photo: The Room and Tag panels of the contextual tab while placing rooms
ControlWhat it does
Place Rooms AutomaticallyFills every enclosed region in one click, then reports how many rooms it made
Highlight BoundariesHighlights every element currently bounding rooms. The fastest way to find a gap
Tag on PlacementOn by default, so a tag arrives with each room
OrientationThe text direction of the tag. Pick Vertical for long narrow rooms
Leader LineDraws a leader from tag to room, for rooms too small to hold the text

Not every boundary is a wall. A living room opening into a dining room needs a virtual edge, and the Room Separator tool draws exactly that.

The Draw panel of the Room Separator tool Photo: The sketch tools, the Offset and Radius boxes and the Chain button

A separation line is a drawn line, not an element. It builds nothing in the model, never schedules, and is usually switched off on printed drawings. Its only job is to stop a room.

To merge two rooms, do the reverse: delete the separation line or clear Room Bounding on the dividing wall, then delete one of the two rooms. A breakfast bar between kitchen and dining is the usual case, since the drawings treat it as one space.

Room properties and the 3048 trap

Select a room and the Properties palette falls into three groups.

The Properties palette of a room Photo: The Constraints, Dimensions and Identity Data groups of a room
No.PartWhat it does
1Constraints groupLevel is the floor level. Upper Limit and Limit Offset set the ceiling of the room volume
2Dimensions groupArea, Perimeter, Unbounded Height, Volume and Computation Height, all greyed because Revit computes them
3Number and NameThe two boxes you fill in, and the two that reach the tag and the schedule

The default in Limit Offset deserves attention: 3048, which is ten feet in millimetres. It is a leftover of the imperial origin inside the Metric template, harmless but meaningless on a metric project.

Change it to the real storey height with the very first room. For a 3600 storey, set Limit Offset to 3600, and the room volume finally means something.

The Volume box usually reads Not Computed. Revit only calculates volume when told to, and that switch lives in the dialog covered further down.

Revit room tag: three types and the safe way to edit

Room tags belong to the Room Tags category, and the Metric template ships three types.

The three room tag types Photo: The Type Selector for a room tag with its three types
TypeWhen to use it
Room TagName and number only. For ordinary layout plans
Room Tag With AreaAdds the area. For occupancy plans and handover drawings
Room Tag With VolumeAdds the volume. Mostly for air conditioning calculations

A room tag holds two stacked text boxes: the name on top, the boxed number below. At small scales they almost touch, and clicking the lower one then typing a name puts the name into the number field.

The safe method is to hover over the tag, press Tab until the status bar reads Rooms, click to select, then edit Name and Number in the Properties palette. Remember to click Apply.

One room has one volume but can carry a tag in every view. Deleting the tag in the architectural plan leaves the ceiling plan tag alone, and does not delete the room. Autodesk covers tagging an existing room on Tag a Room.

Revit color scheme: colouring a plan by room name

A coloured plan is the easiest drawing in the set to read, and usually the first one a client looks at. Revit builds it from room parameters, so the colours can never drift from the names.

The tool sits on the Annotate tab, Color Fill panel, Color Fill Legend. Many people hunt for it in vain, because it feels as though it belongs with the Room & Area panel.

Click the tool, then click an empty spot on the sheet. Release 2027.2 immediately places an empty legend reading No colors defined and asks nothing further. Older releases opened a Choose Space Type and Color Scheme dialog at this point, and Autodesk's Add a Color Fill Legend still describes that older behaviour. This was checked directly on build 27.2.

Select the legend you just placed and click Edit Scheme to reach the main dialog.

The Edit Color Scheme dialog Photo: The Edit Color Scheme dialog with the Name scheme selected
No.PartWhat it does
1Schemes groupCategory picks the object class; below it are the ready-made schemes such as Name and Department
2Title and ColorTitle is the heading on the legend; Color picks the parameter that drives the colours
3Value tableSix columns: Value, Visible, Color, Fill Pattern, Preview and In Use
4Options groupInclude elements from links decides whether rooms in linked files are coloured too

Choosing the Name scheme on the left does most of the work. The table on the right then lists exactly the room names in the project, one colour each.

A plan after the colour scheme is applied Photo: A plan coloured by room name with its automatically generated legend
No.PartWhat it shows
1Living roomFilled from the matching row of the value table
2Dining roomEvery distinct room name receives a distinct colour
3BathroomAdd a room with a new name and Revit adds a row and invents a colour
4LegendLists exactly the values in use, each with its colour swatch

The colours Revit invents are very pale and print almost white, so they nearly always need editing. The Visible column hides a value from the plan without deleting it, and a row whose In Use reads No is surplus and can be removed.

A colour scheme belongs to the view, not to the project. To colour every floor, set it once in a view template and apply that to the whole set of plans, as covered in how to hide elements in Revit.

Room area in Revit: the four wall references

Before trusting any area figure, check where Revit is measuring to. Open the drop-down arrow on the Room & Area panel title and pick Area and Volume Computations.

The Computations tab Photo: The Area and Volume Computations dialog with its Volume and Room Area groups
No.PartWhat it does
1Two tabsComputations sets the rules, Area Schemes manages the area schemes
2Volume ComputationsAreas only is faster; Areas and Volumes makes Revit compute room volumes too
3Room Area ComputationThe four wall references
ReferenceWhat it means
At wall finishMeasures to the finished face inside the room. This is usable floor area, close to how handover is checked
At wall centerMeasures to the wall centreline. A larger figure, common for apartment sale contracts
At wall core layerMeasures to the face of the core, ignoring plaster and cladding
At wall core centerMeasures to the centre of the core

The gap is not small. On a 220 wall, finish face and centreline differ by 110 mm on each side, so 220 mm across the room.

This is a project-wide setting, not a per-room one. Change it and every room area in the file moves, including schedules already built. Settle it at the start of the project and write it into the drawing conventions.

Revit area plan and the area boundary

A room measures usable space and stops at the wall face. An area measures to a boundary you place yourself, which can wrap the outer face of the wall. The two answer different questions, and most projects need both.

Click the arrow under the Area button and choose Area Plan.

The New Area Plan dialog Photo: The New Area Plan dialog with the Type box, the level list and the duplicate check
No.PartWhat it does
1Type boxPicks the area scheme. The Metric template ships Gross Building and Rentable
2Level listPick one or more levels to create area plans for
3Do not duplicate existing viewsOn by default; leave it so that no duplicate views are made

Click OK and Revit asks whether to draw boundary lines automatically around all external walls. Answer Yes and the boundaries come out nearly right, needing only a few edits; answer No and the view arrives empty for you to trace with the Area Boundary tool.

An area plan of one level Photo: The magenta area boundary following the external walls, with the area tag
No.PartWhat it shows
1Area boundary lineA magenta line along the external walls, editable by dragging its ends like any line
2Area tagTwo lines: the name and the area figure

The two figures always land close together but never match. An area follows a boundary and so counts the partition walls, while rooms stop at the wall face and leave them out.

That is why you cannot add room areas to get floor area. For gross floor area as local practice defines it, drag the boundary out to the outer face of the wall, which is precisely what an area object allows and a room does not.

Try it: place rooms and build a coloured plan

A forty minute exercise. Work on a model with the walls and floor of one storey already built.

  1. Open Area and Volume Computations, set Room Area Computation to At wall finish, choose Areas and Volumes, and click OK.
  2. Run Room and click Place Rooms Automatically, noting how many rooms Revit reports.
  3. Find any room reading Not Enclosed, use Highlight Boundaries to locate the gap, and close it with a wall or a room separator.
  4. Name and number every room to a per-floor convention, starting at 101.
  5. Select all the rooms at once, set Limit Offset to the real storey height, and click Apply.
  6. Draw a Room Separator between the living and dining areas, then place a new room in the part you split off.
  7. Switch the tags to Room Tag With Area and check the figure against the Area box in Properties.
  8. On Annotate, click Color Fill Legend, place it clear of the plan, then click Edit Scheme and pick the Name scheme.
  9. Change the bathrooms to a stronger colour and note the colour values you chose.
  10. Switch Room Area Computation to At wall center, read one room area again, and record the difference from step 1.

Step 10 carries the lesson: the same model, a different reference, a different number. Schedules read these figures, and building them is covered in schedules in Revit.

Frequently asked questions

A room reads Not Enclosed. How do I fix it?

The region is not closed. Use Highlight Boundaries so Revit highlights every bounding element, find where the chain breaks, and close it with a wall or a room separation line.

I deleted the tag but the schedule still lists the room. Why?

A tag and a room are different objects. Deleting the tag only hides the text; the room stays in the file and still schedules, with an area of zero. Filter the schedule by zero area and delete those rows.

Why does Volume read Not Computed?

Volume calculation is off. Open Area and Volume Computations and choose Areas and Volumes. Fix Limit Offset to the storey height at the same time, or the volume is computed over 3048 mm.

Do room areas add up to the floor area?

No. Rooms stop at the wall face, so the partitions are not counted, while an area measures to a boundary that can include the walls. The two figures measure different things.

About the author

Dr. Nguyen Manh Tuan — BIM lecturer at the Institute of Information Technology in Civil Engineering – Hanoi University of Civil Engineering