1. Sketch the outline before you measure

Draw the room’s approximate shape and mark each corner. Include alcoves, chimney breasts, columns and built-in cupboards. Give each wall a letter so your measurements remain easy to follow. The first sketch does not need to be to scale.

2. Record every wall segment

Measure between the finished wall surfaces and record the units beside your numbers. For a wall with a recess, record each section as well as the overall span where possible. Avoid mixing centimetres and millimetres without an explicit conversion. If you measure in millimetres, keep that convention throughout your notes.

3. Position doors and windows

For each opening, record its width and distance from a clearly identified corner. Note the door swing direction so your plan shows where the door needs space to open. Record window sill height and opening height if you want to describe the room in 3D.

4. Add heights and fixed features

Measure ceiling height where it changes, including slopes or bulkheads. Mark radiators, steps, structural projections and any fittings that restrict a layout. A clear floor area can still have an obstruction above it, so write down relevant heights as well as floor positions.

5. Check your measurements before drawing

Repeat important measurements. Where practical, compare a wall’s overall length with its component sections. Diagonal measurements can help you notice when a room is not square. If two readings disagree, record the uncertainty and measure again rather than silently averaging them.

6. Keep a usable record

Label the room, date, measurement units and any areas you could not access. Keep photographs alongside your notes if useful. These measurements will give you a head start when the FreeFloorplan3D editor launches. They are planning information; verify critical sizes before construction or purchasing fitted items.

Keep planning

2D vs 3D floorplans: which view do you need? →

How to prepare your first building floorplan →