MBS Floor Plans Software – Where and how to start surveying an Irregular Shaped Room

Note: This page is a WIP and subject to regular changes and updates.

Topic2_ImageBFirst let’s define an irregular shaped room; it’s one where not all corners of the room are 90°, for example.


You can start to minimize any errors, by carefully selecting your start point. When selecting the first wall in an irregular room, you should select the first straight wall and vertex after the angular wall to start. You also have to create a room in a clockwise direction, so in these Topic2_ImageCtwo room examples the start points and direction would be:


The first wall of a room forms the baseline for any computations and will not “move“, everything swings from it. Its length may change in an adjustment but the orientation will not change. Ideally this wall would also be an external one that links to your footprint with your outside control, rather than an internal wall, to minimize any errors. But in the case of an irregular room it is more important the angular walls are measured last to minimize any errors. For the room (kitchen) to be surveyed in lesson 1, where is the best place to start: A, B or C?

Topic2_ImageDIt’s A and coincidentally the starting wall is also an external wall that links to the building footprint and external survey control.

Information on the Methods of computing angles in an Irregular Shaped Room

Lesson 1: Using the Room Adjustment Tool with NO Cross-Braces

Lesson 2: Using the Room Adjustment Tool with Cross-Braces

Lesson 3: Using the Type Bearing Tool

Lesson 4: Using the Calculate Angle Tool

Lesson 5: Moving/Transforming a Room to a Measured Point

Lesson 6: Using the Match Bearing Tool

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