open source 3D design sw: blueprint3d

furnishup/blueprint3d: Build interior spaces in 3D @ GitHub (MIT license)

This is a customizable application built on three.js that allows users to design an interior space such as a home or apartment.

Blueprint 3D - Example

maybe related?

aalavandhaann/blueprint-js @GitHub

"old style" Java based, GPL licensed similar purpose tool

SweetHome3D/SweetHome3D: UNOFFICIAL, maintained mirror of official SVN repo of Sweet Home 3D. Feel free to use it as base for developing your new contributions. @GitHub

popular "freemium" closed source alternatives

Planner 5D: House Design Software | Home Design in 3D

3D Design Software | 3D Modeling on the Web | SketchUp

and other "alternatives"

Planner 5D Alternatives: 25+ Interior Design and similar apps | AlternativeTo