Room 3D Design: How We Built 14 Daylit Rooms for Renders

Short answer: to design a room in 3D that renders convincingly, start from real measurements. Set the interior width, depth and ceiling height, give the walls real thickness, cut doors and windows into them at real sizes, furnish to standard heights, light the room with one sun from a known angle, and shoot from eye height. Below is how we did exactly that for the 14 rooms of Linden House, with every size and setting.

Most results for "room 3D design" are planner apps for arranging your own furniture. This guide is for the other job: building a room as a 3D scene for architectural, interior or product renders. Every number comes from the delivered scene files and our live product pages, checked in October 2026.

The 14 rooms at a glance

Each room is its own scene file with its own shell, lights and cameras. Interior sizes are measured wall to wall; triangle counts are the Realtime totals listed on each product page.

Together the 14 scenes draw on 169 assets and 1,743,543 triangles, all sold together as Linden House: All Scenes or room by room from the Linden House collection.

Step 1: build the shell at real size

A room reads as real when its proportions are real. Ceiling heights in our set run from 2.5 m in the family bathroom to 3.2 m in the period townhouse salon and 3.6 m in the double-height loft. Most living spaces sit at 2.6 to 2.7 m, which is what a camera at eye height expects to see.

Walls get real thickness too: the collection plan sets 0.12 m for interior walls and 0.30 m for exterior walls. Thickness matters because light enters through the depth of the reveal, and a paper-thin wall gives a window no sill and no shadow edge. We changed it where the room needed it. The Reading Nook has a 0.40 m exterior wall, because the inward-opening casement would otherwise leave only a 0.125 m sill, too shallow for the row of books that sits on it.

The shells (walls, floor and ceiling slabs) ship inside each scene but are not sold as separate designs. Archviz teams usually model their own architecture in CAD or BIM; what they need is everything that fills it.

Step 2: cut openings, do not fake them

Every door, window and recessed light in Linden House carries a cutter object that cuts its own opening into the wall. Move a window and the hole moves with it, with clean reveals, instead of a frame floating on a solid wall. Across the full set, 13 of the 169 assets come with cutters.

Sizes follow common European metric practice. Interior door leaves are 2.04 m tall and 0.04 m thick, in 0.7, 0.8 and 0.9 m widths. Windows and doors also come as width and wall-depth options, each rebuilt as its own files, so a deeper wall gets a deeper frame instead of a stretched one. Our guide to window and door 3D models lists the sizes and how the wall cutters work.

Step 3: furnish to standard heights

Furniture placed at the wrong height is the fastest way to make a room look like a model. The collection plan fixes these standards for every Linden House asset:

Kitchen modules come in widths from 0.30 to 0.90 m, so a run can be planned the way a kitchen fitter would plan it. The kitchen 3D design guide covers cabinet sizes, counter heights and islands, and our guide to office chair and desk 3D models does the same for home office corners. Materials matter as much as sizes: floors and worktops use the same physically based finishes as our wood textures for 3D interiors.

Step 4: one sun, one time of day

Each room is lit by a physical sky and a single sun from a fixed angle, so the shadows tell one consistent story. The angle sets the mood more than any other setting:

• Golden hour: the Mid-Century Lounge has the sun at 10 degrees and a warm 3,200 K colour through the picture window.
• Early morning: the Primary Bedroom uses 16 degrees, filtered through sheers.
• Low winter sun: the Scandinavian Living Room uses 20 degrees through the picture window.
• Midday: the Compact Studio Apartment uses 40 degrees through two casements; the Open Kitchen uses a bright overcast sky with a soft sun patch.
• Soft sky only: the Family Bathroom and Spa Ensuite are lit mostly by diffuse sky through frosted glass, plus warm practical lights.

Window portals help the render engine sample light coming through the openings, and lamps inside the room are real light sources that can be switched on or off. In the Reading Nook, the tripod floor lamp is a 2,700 K bulb that is on by default. White balance is set per room against the wall paint, so a warm white wall stays warm white instead of turning blue in daylight.

The scenes are set up for Cycles with denoising, 128 samples with adaptive sampling and the AgX view transform. That is a starting point for preview renders; raise samples for final output.

Step 5: the same seven cameras in every room

Consistent cameras make a set of renders look like one shoot. Every Linden House scene ships with the same seven:

Two-point perspective uses lens shift instead of tilting the camera, which is the convention in architectural photography. If you add your own cameras, keep them between 1.35 and 1.50 m for eye-level views; a camera at standing head height or higher makes a room feel smaller.

Placement slots: room for your own products

Rooms built for marketing need space for the thing being marketed. Each scene marks seats, surfaces and shelves as placement slots, each with a size envelope. In the Reading Nook, the armchair seat slot is 0.50 x 0.45 x 0.60 m and the side table surface slot is 0.40 x 0.40 x 0.45 m. The Open Kitchen and Dining has 36 slots across shelves, worktops and seats, and the Scandinavian Living Room and Industrial Loft each include a dedicated product slot. Drop a product model onto a slot and it sits at the right height, already in the light. When a product needs a clean studio set instead of a room, see our guide to 3D product visualization backdrops.

Twelve of the 14 scenes also ship as Realtime BLEND and GLB files for web and real-time use; the Country Kitchen and Townhouse Salon ship as BLEND. If you are new to bringing models into Blender, our guide to checking Blender models before you buy covers formats, scale and materials.

Common questions

How do I make a 3D layout of a room?

Measure the room's width, depth and ceiling height, then build the floor, walls and ceiling at those sizes with real wall thickness. Add doors and windows where they really are, place furniture at standard heights, and check the result from a top-down orthographic view before you light it.

How do I create a 3D model of my own room?

Planner apps are quickest for arranging furniture. For renders, model the shell in Blender or your CAD tool from a tape-measured plan, then fill it with assets built at real size. Linden House assets are in meters with Z up, so they drop into a measured shell without rescaling.

Where can I find 3D room models for rendering?

Look for complete scenes that include lighting and cameras, not only furniture. Check that the listing states real dimensions, a native .blend file and a clear license. All Linden House scenes are under the Premade3D Standard License, which covers commercial and client work.