Software · 3D & BIM

3D building design software — model a building online, free

CivilOS is 3D building design software that runs in a browser tab. You draw levels, walls, floors, columns and beams, drop doors and windows into the walls that carry them, orbit the result in 3D, generate elevation views and export the model as GLB, DXF or IFC4. It is aimed at civil engineers, architects, draughtsmen, builders and students in India who want a working 3D model of a real building without buying a licence or waiting for an installer.

What you can do

Three modules cover 3D work, and they sit side by side in the same app so you can move a project between them without exporting anything.

Feature	What it does	Export
BIM Studio (3D)	A 3D building and site model with more than 40 tools — massing, storeys, roofs, terrain and surrounding context	GLB, GIF, DXF
Structure X-ray	Switches the architecture off and shows the frame underneath: columns, beams and slabs, so you can see how the building actually stands up	GLB
Indo-Revit — levels and walls	Revit-style authoring: define levels, then draw walls that belong to a level and carry a real thickness	IFC4
Hosted doors and windows	An opening belongs to its wall. Move or delete the wall and the opening goes with it — it is not a hole you drew twice	IFC4
Floors, columns, beams	Real building elements rather than extruded outlines, so they carry their own data into the schedules	IFC4
3D and elevation views	Orbit the model, then generate elevation views of the faces you need for a drawing set	IFC4, printed sheet
Schedules and IFC inspector	Element schedules read straight from the model; the inspector opens an IFC file and shows you its entity tree	IFC4
Interior Studio	Rooms, furniture and finishes, viewed at eye level so a client can walk through a room instead of squinting at a plan	On screen
Create Your OWN Plan	Concept floor plans for a home, office, shop, mall, warehouse or PEB shed — a starting footprint for the 3D	PDF sheet, DXF
Site Geo (GIS)	Draw the plot on live satellite imagery and get its area and FAR before you model anything on it	GeoJSON, KML, DXF

How it fits an Indian project

A 3D model on its own does not get a building built in India — the model has to hand over to a space programme, a drawing set, a quantity statement and a rate. CivilOS keeps that chain inside one app.

Space Planning works out the area programme against National Building Code references — room sizes, circulation, the shared vertical core — with no AI guessing in the loop, so the number you get is one you can trace. Site Geo gives you the plot area and FAR from the satellite view, which is usually the first real constraint on how many floors you are allowed to model. Once the model exists, Quantity Survey and BBS produces the takeoff and a Bar Bending Schedule to IS 456, IS 2502, SP 34 and IS 13920 with each row's formula visible for checking, and Cost Estimator prices the work against CPWD DSR 2023 — all 3,047 items shipped with the app as data — or a State PWD schedule of rates, or your own market rates. BOQ and Estimation then turns that into a sanctioned estimate or an RA bill in the government format that a division office expects.

How to model a building in 3D

Fix the footprint first. Either draw the plot in Site Geo to get its true area and setbacks, or generate a concept layout in Create Your OWN Plan and export it as DXF.
Set your levels. In Indo-Revit, define the storeys — plinth, ground, first, terrace — with their heights. Every wall and floor you draw afterwards belongs to one of them.
Draw the walls. Give each wall its real thickness (230 mm brick, 150 mm partition) so the 3D is dimensionally honest rather than a diagram.
Host the doors and windows. Click a wall and place the opening into it. Because it is hosted, a later change to the wall carries the opening along.
Add floors, columns and beams. This is what makes the structure X-ray meaningful — the frame is modelled, not implied.
Look at it. Orbit in 3D, generate the elevation views you need, and use Interior Studio when the discussion is about how a room feels rather than how the building stands.
Check the schedules. Element schedules come off the model, so a wall you forgot to give a thickness shows up as an obvious gap in the table.
Export. IFC4 to hand the model to a consultant, GLB for a 3D viewer or a renderer, DXF for drawing work, and a plotted sheet when the deliverable is paper.

What CivilOS does not do

Being specific about the gaps is more useful to you than a feature list that quietly overstates itself. In 3D and BIM work, CivilOS does not have:

No rendering engine. No ray tracing, no material library, no lighting setup. Views are real-time shaded. Export GLB and render elsewhere if you need a photoreal image.
No clash detection or model coordination. There is nothing of the Navisworks type here — you cannot run a services-versus-structure clash test.
No 4D or 5D simulation. The Project Scheduler does CPM, WBS and critical path, but the programme is not linked to the 3D model as an animated build sequence.
No point clouds or scan-to-BIM. You cannot bring survey scan data into the model.
No structural analysis or design. Nothing solves for forces, deflections or reinforcement. CivilOS models, details, schedules and quantifies — sizing stays with your structural engineer.
No MEP calculation. There are MEP symbols and discipline layers for drafting services on a plan, but no load, duct, pipe or sizing engine.
DXF out, not DWG. CivilOS reads DXF and DWG, and writes DXF (R12). It does not write DWG or RVT.

Where a free browser tool actually fits

Desktop BIM and 3D packages — the ones that dominate large architectural and infrastructure practices — are built for full production documentation: coordinated multi-discipline models, hundreds of sheets with viewports and external references, photorealistic visualisation, analysis links, and a specification database behind it all. That is genuinely their job, they are very good at it, and CivilOS is not a replacement for them. If your project needs clash detection across services or a rendered walkthrough for a marketing brochure, you will still use them.

A free browser tool fits a different, earlier and much more common part of the work: getting a real 3D of a house, shop, warehouse or PEB shed in front of a client this week; testing whether a massing fits the plot and the FAR; producing a model a junior can build without a workstation; teaching students what a hosted opening or a level actually means; and doing all of it from a site office laptop where no licence exists and no IT department is going to install anything. If the model later needs to move into a desktop package, IFC4 and DXF are how it travels.

Open BIM Studio and model a building in 3D — free, in your browser →

Frequently asked questions

Can I design a building in 3D without installing any software?

Yes. CivilOS runs entirely inside a browser tab. There is nothing to download, no licence key and no serial number, and you can install it to your home screen as a PWA so it opens like an app. It is free to use; the AI assistant features are subject to fair-use limits.

Does CivilOS produce photorealistic renders?

No. There is no rendering engine, no ray tracing, no material or lighting library. The 3D views are real-time shaded views meant for design decisions and client explanation. If you need a photoreal image, export the model as GLB and render it in a package built for that.

Which formats can I export the 3D model to?

BIM Studio exports GLB (for 3D viewers and renderers), animated GIF and DXF. Indo-Revit exports IFC4, which most BIM applications can open. CivilOS writes DXF but not DWG, and it does not write RVT files.

Is this BIM or just 3D modelling?

Both, in two different modules. BIM Studio is a 3D building and site modeller with over 40 tools. Indo-Revit is Revit-style BIM authoring: levels, walls, doors and windows hosted in their walls, floors, columns, beams, elevation views, schedules and IFC4 export. Neither module does clash detection, 4D or 5D simulation.

Can CivilOS analyse or design the structure I model?

No. There is no analysis or design solver of any kind. CivilOS models geometry and produces detailing, schedules, quantities and a Bar Bending Schedule to IS 456, IS 2502, SP 34 and IS 13920. Member sizes and reinforcement must come from a licensed structural engineer.

Will it run on a laptop or a phone?

It runs in any modern browser on Windows, macOS, Linux, Android and iOS. Because the 3D view is drawn live, a phone or a low-powered laptop handles a house or a shed comfortably and will feel slower on a very large model. The interface is available in 24 languages including Hindi, Telugu and Tamil.

Can I take quantities and a cost off the building I model?

Yes, in the same app. Quantity Survey and BBS handles takeoff and reinforcement scheduling, BOQ and Estimation produces an IS-code bill of quantities with rate analysis, and Cost Estimator prices it against CPWD DSR 2023, State PWD schedules of rates or your own market rates.

Draft for checking. A 3D model is a design aid, not an approval. Member sizes, reinforcement, fire and services design and municipal compliance must be checked and signed off by the licensed professionals responsible for the project.