# Rooms

Source: https://meptools.com/tools/plant-room-studio/docs/rooms/

A **room** is the bounded floor area you lay equipment into. Every project has a room; its walls
define the boundary that equipment must stay inside and the envelope the validator checks
clearances against.

## Creating a room

Press **R** (or pick the room tool) and draw the room outline, then drag the edge handles to
match your architectural shell. Snapping to the grid keeps edges aligned — toggle grid snap with
**G** and grid visibility with **Shift+G**.

![Drawing a room and adjusting edge handles](./_assets/rooms.png)

## Setting dimensions

Select an edge or the room and type exact internal dimensions in the inspector. Values are in
**millimetres**, measured from the coordinate origin at the bottom-left corner (see the
[coordinate system](/tools/plant-room-studio/docs/coordinate-system)).

```
Width:  8400 mm
Depth:  6200 mm
Origin: 0,0 (bottom-left)
```

## Walls, doors, and columns

- **Walls** have a thickness and form the room body. Wall-mounted equipment is checked so it
  does not overlap the wall body.
- **Doors** sit in a wall and are checked for clearance against equipment passing through them.
- **Columns** are obstructions inside the room. Equipment footprints and clearance zones are
  validated against columns just as they are against walls and other equipment.

## Rooms and validation

- Equipment must sit **fully inside** the room boundary — anything extending outside is flagged
  as an error.
- Clearance zones that intersect a wall or column raise a warning.

See [Clearance validation](/tools/plant-room-studio/docs/validation) for the full rule list.