AI Floor Plan Generator
Describe a home in one sentence — get a drawn, measurable, editable plan
Most "AI floor plan" tools generate a picture of a floor plan. It looks convincing until you try to use it: the walls have no thickness you can trust, the dimensions are decorative, the labels are half-words, and there is nothing to export. Gridsnap does the opposite. The AI never draws anything — it only reads your sentence. The plan itself is produced by a layout solver working in integer millimetres, and it isn't shown to you until it has passed the same architectural rule check used on hand-drawn plans.
3-bedroom single-storey house, about 120 m², open-plan kitchen and living, entrance from the north
Small 45 m² flat: one bedroom, bathroom, kitchen/living, entrance from the south
Summer cabin ~60 m² with a sauna, two bedrooms and an open kitchen/living room
In the editor: New → ✨ Describe your home. You see the room list and a preview before anything replaces your current plan.
How a Sentence Becomes a Plan
Describe the home
One sentence, the way you'd tell an architect: "3-bedroom single-storey house, about 120 m², open-plan kitchen and living, entrance from the north." Room count, total size, which rooms are combined, which side you arrive from — anything you leave out gets a sensible default.
The brief becomes a room program
The AI reads your sentence and turns it into a list of rooms with target areas and relationships — nothing else. It never draws a single wall. Its whole job is understanding what you asked for, which is the only part of this that needs language.
A solver draws the plan
A deterministic layout solver sizes the envelope, subdivides it so every room hits its net area, opens doors along a real circulation route, composes windows façade by façade to satisfy the daylight rule, and furnishes each room from its kit. Same maths as the drawing tools — integer millimetres throughout.
The rule engine has to sign it off
Every candidate layout is run through the plan checker. A plan that fails is thrown away and the search continues — you get an error-free layout or nothing at all. Then you preview it, re-roll for a different arrangement as often as you like, and open it in the editor as an ordinary plan you can change.
The Rules It Has to Satisfy
Anyone can subdivide a rectangle into rooms of the right size. What makes a layout livable is everything between the rooms — where you walk, what you walk through, what you can reach. Those are written down as rules the generator has to satisfy, not preferences it tries to honour:
Every room reachable properly
The door graph is solved as a routing problem, not guessed. An ensuite may open off its bedroom; a washroom may not open off the living room. No room is ever a corridor to another.
Bathrooms where you'd want them
Each bedroom is scored on how many doors you pass to reach the nearest washroom. Past three, the layout is rejected. The house's only bathroom never ends up behind a bedroom door.
One of the things you only need one of
One dining table, one laundry, one set of white goods — house-level policy, so an open-plan kitchen-living room doesn't get a second table it has no room for.
Daylight before decoration
Windows are composed per façade until each habitable room has glazing of at least an eighth of its floor area — the classic daylight rule of thumb — instead of being sprinkled evenly around the outside.
Rooms wide enough to use
A room isn't just an area target: the solver holds a minimum usable width per room type, and the checker measures the real narrowest dimension of the finished shape.
A sauna in the right sequence
Ask for a sauna and you get the whole complex in order — hall, changing room, bathroom, sauna — with one way in. Below about 90 m² the changing room folds away rather than being squeezed in.
When a full program can't satisfy everything, the solver would rather drop an optional room — a changing room, storage, a utility — and give its floor area to the bathroom than hand you a laundry you have to walk through a bedroom to reach. A stranded room is worse than no room.
What You Get, and What You Do Next
The output isn't an image or a PDF you have to accept — it's a Gridsnap document. Walls with real thickness, doors with swings, windows with sills, named rooms with their net m², and furniture placed against the walls it belongs on. Open it and every tool applies: drag a partition and the dimensions follow, switch to 3D and walk through it, print a vector PDF at 1:100, or hand your architect a layered DXF.
That's the point of generating a plan at all: not to replace the design, but to skip the blank canvas. Ten seconds of typing gets you something concrete to argue with — and arguing with a drawn plan is how briefs turn into buildings.
Common Questions
Can AI really generate a floor plan?
It depends what you mean by AI. An image model can produce a picture that looks like a floor plan — with unmeasurable walls, invented symbols and garbled labels — and that picture is not a plan: you can't dimension it, print it to scale or hand it to a builder. Gridsnap splits the job. Language understanding is what the AI is good at, so it reads your brief into a room program. Geometry is what solvers are good at, so a deterministic layout engine draws the actual walls, doors, windows and furniture in real millimetres. The result is an editable CAD model that exports to vector PDF and DXF.
What exactly do I type?
A sentence describing the home: how many bedrooms, roughly how big, which rooms should be open-plan, and which side the entrance is on. For example "Small 45 m² flat: one bedroom, bathroom, kitchen/living, entrance from the south" or "Summer cabin ~60 m² with a sauna, two bedrooms and an open kitchen/living room". Stating an exact footprint (say 12 × 9 m) makes that the envelope; naming a room's area holds that room at that size while everything else adapts.
Is the generated plan any good, or is it a toy?
It has to pass the same plan checker that reviews hand-drawn plans before it is shown to you — circulation, door swings and clearances, bathroom fixtures, kitchen work triangle, bed placement, room sizes and daylight. It is a credible starting point that a person then edits: the entrance in the right place, the bedrooms sized, the kitchen workable. It is not a permit drawing, and it doesn't know your site, your budget or your local building code.
Can I get a different layout for the same brief?
Yes — "Try another layout" re-runs the solver with a new seed, which is instant, local and free. Only re-reading a new brief involves the AI at all. In practice you generate a few, keep the arrangement you like, and take it into the editor.
What can't it do?
It generates a single storey — add further floors yourself in the editor. It works in metric, draws straight walls only (no curves or roofs), and it doesn't design elevations or exteriors. If the rooms you asked for genuinely can't fit in the area you gave, it says so rather than drawing something unusable.
Is it free?
Describing a home is part of Gridsnap Pro ($9/month or $90/year), which also includes the pro-depth plan check, AI notes and fixes, unlimited cloud projects and version history. Drawing plans by hand in Gridsnap — with 3D, elevations and vector PDF/DXF export — stays free forever, with no watermarks and no account needed.
Does my brief get used to train an AI model?
No. Your sentence is sent to the language model only to be turned into a room program for you, and the plan itself is drawn in your browser. Plans stay local and private by default — data is uploaded only if you explicitly enable account sync or create a share link.
Prefer to start from something proven? Browse the floor plan templates — complete, drafting-correct plans that open in one click. Or learn the method yourself with how to draw a floor plan.
Describe your home
A sentence in, a real plan out — then edit it like any other drawing.
Open Gridsnap Editor