HouseSense

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Why is furniture drawn as flat rectangles on a floor plan?

Because a floor plan is a straight view from above: a piece of furniture is shown as the floor area it occupies. The rectangle isn't a simplification of the furniture — it's its real footprint, and that's exactly what you need when furnishing the room.

Short answer: a floor plan is the home seen straight from above, so a piece of furniture is shown as the floor area it takes up — the sofa's 210 × 90 cm, the bed's 180 × 200 cm. The rectangle isn't a poor drawing of the furniture; it's the furniture's footprint to scale, and it's the only thing that can answer whether the piece will fit there. Detailed furniture drawings with shading and upholstery make the floor plan harder to read and hide the very measurements it exists to show. Height and appearance belong on an elevation or in a 3D model.

The rectangle isn't a simplification — it's what you see from above

The reason is the same as for everything else on a floor plan: the plan is a horizontal slice through the home at roughly 1.2 metres up, with the ceiling lifted off, looking straight down. Look at a bed from above and you see a rectangle. Look at a dining table from above and you see a slab — a rectangle or a circle. Look at a sofa from above and you see a rectangle with a small step, where the back is thicker than the seat.

Furniture's flat rectangles on a floor plan aren't a stylisation architects invented. It's the same rule that makes walls two lines and windows holes: everything is drawn as it looks from above, at a fixed scale.

What the rectangle can answer that a picture can't

Furnishing questions are almost always area questions: will the bed fit there? Can you get past it? Is there room to pull the chair out? All of that is decided by the footprint and by the empty floor around it.

A beautifully rendered piece of furniture with shading and upholstery answers none of the four questions above. Worse: it looks bigger or smaller than it really is, because the eye reads richness of detail as size. A sofa drawn with thick cushions looks larger than the 210 cm it actually is.

Real footprints: the measurements you can rely on

If you want to furnish a floor plan yourself, these are the figures to draw. They're typical sizes — always measure your own furniture before ordering anything.

And the clearances that need to sit around the furniture if the room is going to work:

The maths: will the dining table fit in the living room?

Say the dining area in the living room is 3.20 m wide, and you want a 90 × 180 cm table with chairs all the way round.

The table takes up 90 cm in width. You need 80-100 cm behind each row of chairs, so 2 × 90 = 180 cm. Total: 90 + 180 = 270 cm. With 320 cm available, there's 50 cm to spare — that's enough. If the space were only 250 cm, the chairs on one side would hit the wall every time someone stood up.

That's exactly the kind of calculation flat rectangles are built for. On a floor plan with real footprints, you can measure it with a ruler in thirty seconds. On a perspective interior rendering, you can't measure it at all.

The symbols that still aren't plain rectangles

Some fixtures and fittings have their own outlined symbol, which has become standard because they exist in almost every home:

What all of them have in common is that they're still seen from above and still drawn to scale. The symbol is only a recognisable outline on top of the footprint — not an illustration.

When furniture should come off the drawing

Furniture on a floor plan is useful for laying out a room and for giving a buyer a sense of scale. But it should be removed in three cases:

That's why "show/hide furniture" is a completely ordinary button in drawing tools — including in HouseSense, where furniture can be toggled off when the drawing is heading out to a tradesperson.

How HouseSense does it

HouseSense follows the architectural convention: on the floor plan, furniture is shown as flat rectangles with the piece's real footprint. No shading, no perspective, no icons bigger than the furniture itself. That keeps the drawing readable and true to scale — you can lay a ruler on it and get the correct answer.

The proper shapes, on the other hand, live in the 3D model. There, a sofa has a sofa shape, a table has legs, and a TV hangs on the wall at the height it actually hangs at. The split is deliberate: the plan is for measuring, the 3D model is for understanding. Need to judge whether the table will fit? Look at the plan. Need to judge whether the room feels right? Take a walk through the 3D model.

Try the old method if you're drawing by hand

Want to furnish on paper? The fastest method is still the oldest one: draw your furniture's footprints at the same scale as the floor plan on a piece of card, cut them out, and slide them around the drawing. At 1:50, a 180 cm bed becomes a 3.6 cm piece.

It takes ten minutes and catches the mistakes no 3D visualisation catches: that there isn't 80 cm behind the chairs, that the door hits the chest of drawers, and that there's no route from the sofa to the kitchen that doesn't cut straight through the dining table.

Download on the App Storefor iPhone and iPad — draw or scan

One home is free. Plans for more in the app.

These articles are general guidance, not advice about your particular home. Rules for areas, building work and permits differ from country to country and change over time — always check with the authorities or a professional before you decide anything.