Draw. Furnish. Watch the sun. In your browser.
Builder is a browser-based 3D house designer. Draw walls, cut windows and doors with real booleans, fit a roof, furnish from a CC0 catalogue, sculpt the terrain — and watch the real sun cross your plot. Then share one link and edit the same design together, with voice.
No install. No plugin. Three.js on WebGL2, in the tab.
On load · no account needed
A visitor opens the designer and watches the build: foundation first, floor slabs, then the walls sweep round, windows snap in, furniture lands — and the roof cranes on last while the planting fills in. First click or scroll skips it. It stays off for automation and reduced motion.
Foundation and floor slabs follow the plan, level by level.
Exterior walls first, then interiors — mitred corners, junctions split.
Windows and doors cut real holes — rectangle, circle, triangle.
Pieces drop from the 381-model CC0 catalogue, placement checked.
Gable, hip, flat or shed — auto-fitted to your exact perimeter.
Garden and terrain dress the plot while the wind takes the plants.
The Builder way
A rail of six doors — Design, Outside, Plan, Furnish, Light, Share — with the tools inside as tabs. Everything floats; nothing takes width from the canvas.
Draw walls; the wall graph splits junctions and mitres corners by itself. Cut windows and doors with real booleans. Fit a gable, hip, flat or shed roof to the exact perimeter.
381 CC0 models — garden 135, kitchen 66, decor 42 — Draco-compressed, baked ambient occlusion, instanced. Placement is checked geometrically before anything lands.
Pick a place, a date, an hour — the shadows are the ones the building would really cast on that plot, that day. Play the day in 15, 45 or 120 seconds.
An 11-pass post stack: GTAO, god rays, HDR bloom, hexagonal depth of field with autofocus, ACES tone mapping, film grade. Seven looks save with the design.
Live rooms: edit the same design together with viewer or editor roles and permission areas, presence in every view, and browser-to-browser voice for up to 8 people.
Type what you want — “a big sectional and a reading corner” — and the model returns place, move and remove ops as one undoable step, re-checked geometrically.
Three.js on WebGL2, ES modules served via importmap — no bundler, no build step, no plugin. It runs in the browser you already own.
Placed a ready house from the catalogue? It replaces the design and stays fully editable — walls, openings, materials, terrain. No baked showroom state.
Share the design; a viewer writes nothing — enforced by the server. Editors can be scoped to areas: the outside, the inside, the garden, colours, light.
Why Builder
A designer edits real walls, roofs and terrain, so nothing can be pre-baked. Every view is computed in front of you — orbit, cross-section, first person.
Not a light rig. Solar and lunar positions from the Meeus series, a ~0.01° sun — equinox sunrise due east, midsummer in Warsaw 04:14–21:01.
Not comments about a screenshot. The same design at the same second, a turn wheel so you don't fight over the mouse, and audio that never touches the server.
AI Studio returns three op kinds — place, move, remove — guarded by an allow-list in code. Dropped ops are reported, not hidden. One prompt per click.
60 FPS, <300 draw calls, <250 MB JS heap under a stress design — measured on Apple M4 at 286 draws, 60 fps, 28 MB heap with the full 11-pass stack.
Walk mode
WASD to walk, Shift to run, the mouse looks — pointer lock, the reticle is the pointer. V switches to third person, E opens the door in front of you, Esc steps out. Editing works from inside the house: stand in the room you're changing.
A moment for the tab
1985 – 2026. It rendered, it dongled, and it always wanted a better graphics card. Your house now lives in a tab — and the tab goes where you go: the plot, the client, the kitchen table.
Open the designerWho Builder is for
The design is a URL — it opens wherever the decision happens.
Open the design on your phone, play the day, and see where the evening sun lands on the terrace — before you pour the slab.
Work anywhereDuplicate the design, move a gable, compare the masses — then hand the garden area to the landscape designer without handing over the whole plan.
Architecture studiosPlace one of the 140 ready houses on the plot, walk the buyer through it in first person, and let them change the clinker brick live.
Housing developersCatalogue
Single storey, attic, two storey; gable, hip, flat, shed roofs; none, one or two garage bays. The app opens on a different house each visit.
Garden 135, kitchen 66, decor 42, storage 42, bathroom 21 — Draco-compressed GLBs with baked vertex ambient occlusion, instanced for speed.
Clinker brick, standing-seam metal, clay tiles, herringbone paving, granite setts — procedural PBR built from height fields. No licensing paperwork.
Light
Exactly one shadow-casting light at a time — the sun, or the moon.
Play 24 hours in 15, 45 or 120 seconds. Sun colour keys to elevation — white at noon, gold at 12°, orange on the horizon. Fog and hemisphere light follow the same curve.
Study the whole year over your plot: solstice noon against the earth's tilt, equinox sunrise due east, polar day and night. Click the compass to face north.
Meeus low-precision series, a ~0.01° sun: pick a place, a date and an hour — the shadows your building would really cast.
Every daylit opening carries a RectAreaLight into the room; interior faces use a dimmed indoor ambient. Rooms light correctly instead of glowing.
PCF-soft, fitted to the site — about 2 cm per texel over a 45 m radius. Hard-edged shadows don't survive contact with a real plot.
Draw the plan, raise the gable, and watch the midsummer sun cross the rooms you'll actually live in.
See plot & orientationThe architect holds the structure, the interior designer furnishes, the client walks it and agrees out loud.
See client sign-offStudents draw walls, cut openings and read the sun in a browser tab. One link opens the whole class.
See schools & universitiesPlans & pricing
For looking
$0
Open a house, orbit it, walk it, play the sun. No install.
Free plan includes
For builders · AI included
Draft
Full editing, AI Studio, cinematic renders. Launch placeholder — final pricing pending.
Everything in Free, plus
For teams
Draft
Live rooms, voice, permission areas. Launch placeholder — final pricing pending.
Everything in Pro, plus
For classrooms
Free
Free to start — one link opens the class.
Everything in Free, plus
The designer opens on a ready house that builds itself in front of you — first click, it's yours to edit.
Illustrations by GetIllustrations.com (Angle pack).