Short answer. A floor plan is the flat seen from above, cut through about a metre above the floor. Thick lines are walls, gaps in them are doors and windows, a quarter circle shows which way a door swings, and a row of lines with an arrow is a stair. Sizes are written along the walls or in a table, and the north arrow tells you where the sun comes from. Trust the written sizes, not the drawing, and check one wall with a tape.
How to turn a floor plan into 3DStandard room sizesBuying a flat off-plan
First, what kind of plan is it?
- A listing plan from an estate agent, usually marked "not to scale", with room sizes in a list.
- A developer's plan of a flat sold off-plan, often with furniture drawn in and a table of room sizes.
- An architect's drawing, made to build from, with sizes in millimetres and a scale such as 1:50 or 1:100.
Only an architect's drawing, or your own tape, gives sizes to order a fitted kitchen from.
The symbols
- WallSolid, at its real thickness: thick outside, thin inside
- DoorThe line starts at the hinge; the arc is the floor it sweeps
- Sliding doorA panel along the wall where it slides
- WindowTwo or three thin lines across a gap
- RadiatorA thin rectangle standing off the wall
- StairsA line per step, the arrow points up
Two arcs meeting in the middle are double doors, a dashed line inside the wall is often a pocket door, and a gap with no line and no arc is an open doorway. An outline that steps out from the wall is a bay window. Hatching or a fill colour may mark a structural wall, but drawings differ: never decide a wall can come out from a plan alone.
| Label | Usually means |
|---|---|
| F, DW, WM | Fridge, dishwasher, washing machine |
| C, CPD, ST | Cupboard, storage |
| UP, DN | Stairs going up or down |
| Square with a cross | Shower tray |
Many plans leave radiators out. If a label is not explained, ask.
Sizes and scale
- Written sizes are the ones to trust, usually length first: 4.20 m × 3.10 m (13 ft 9 in × 10 ft 2 in).
- "Max" means the widest point, into a bay or an alcove. The rectangle you can furnish is smaller.
- Millimetres are normal on architects' drawings: 3450 means 3.45 m.
- A scale such as 1:100 works only on the original print; a scale bar still works on a screenshot. "Not to scale" means do not measure the drawing at all.
- Floor area is counted differently from plan to plan, with or without walls and balcony. Compare like with like.
Common mistakes
- Measuring the drawing instead of using the written sizes.
- Trusting the furniture drawn in. Marketing plans often draw beds and sofas too small; a double mattress is 135 to 160 cm (53 to 63 in) wide, and its frame wider.
- Mixing inside and outside sizes. Furniture needs the finished space between walls.
- Reading a mirror image. Layouts often repeat, flipped, across a corridor.
- Assuming one ceiling height. Sloped ceilings and beams appear as dashed lines, if at all.
Check it in 3D
A plan asks you to imagine. Standing in the flat at eye level shows what lines on paper hide: a narrow hall, a door that hits the wardrobe, a kitchen that feels tight with two people in it.
In Flatwalk you upload the plan as a photo, a screenshot or a PDF, and the reader builds the flat in 3D. Fix any wall it misread by typing its length or, if the reading fails, choose "Draw it myself". Then place real furniture from real shops at its true size, measure a hall with the tape measure, and give the address to see the sun through the windows by date and hour. The 3D flat is only as true as the plan and the sizes you give it, so look over the doors and windows it found.
What Flatwalk does that older planners skip
Lights
Add ceiling lights, lamps and LED strips and see the plan's rooms lit, not only drawn.
Your flat in its city
Give the address and the street and buildings around you appear in 3D where the map has them.
Sun for your address
Real sunlight through the windows on the plan, by date and hour.
One piece, in your own room
Through the live camera or in a photo of the room, stand a sofa on your own floor at its true size before you buy.
Detail
Dozens of door and window types, and kitchens, wardrobes and bathrooms built piece by piece.
Made for a thumb
Tap a wall the plan got wrong and type its real length.
Swipe for more. Every picture is the app itself.
One flat, free
Most people plan one home. For that, Flatwalk costs nothing: no trial clock and no card. Reading your floor plan picture is an AI tool with one free try, and drawing, exact wall sizes, furniture, lights, sun and walking are all part of planning one flat for nothing. A membership is for people who want more flats or more AI.
Questions people ask
What do the curved lines on a floor plan mean? A quarter circle beside a door shows the path the door takes as it opens. The straight line is the door, and the end that meets the wall is the hinge side.
How do I find north on a floor plan? Look for an arrow marked N. If there is none, or you doubt it, find the building on a map and turn the plan to match the street.
Are floor plan sizes measured inside the walls? Listing plans usually give room sizes inside the walls, but drawings differ: some measure to the middle of a wall or to bare brick. Measure one real wall to be sure.
What does "not to scale" mean on a floor plan? That the drawing is not exact, so you cannot measure it with a ruler. Use the written sizes instead.
Flatwalk turns your floor plan into a flat you can walk through at eye level, with real furniture at its true size and the sun for your address, free for one flat. It is launching on Google Play; join the waiting list at flatwalk.app.
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