Four classes set the starting point: how many people, for how long, and how much protection. Every shelter is then designed for one site and the people it protects.
The essential fallout shelter. Compact and robust, built to carry a small family through the two weeks after a nuclear event, when fallout radiation falls by about 99.9%.
A full family shelter with separate sleeping, living and plant areas, and room for elderly relatives or staff.
Long-duration shelter for extended families, with redundant systems and higher blast resistance.
Fully bespoke facilities for estates, family offices and organisations, designed entirely around the brief.
Typical design targets. Final figures are set by our structural engineer after the site assessment and written into your contract.
| Specification | Haven | Keep | Citadel | Estate |
|---|---|---|---|---|
| Occupants | 2–4 | 4–8 | 8–16 | 16–40+ |
| Sealed autonomy | 14 days | 30 days | 90 days | 180+ days |
| Internal area | 25–40 m² | 50–90 m² | 120–250 m² | 300 m²+ |
| Earth cover | 1.0 m min | 1.2 m min | 1.5 m min | 2–3 m+ |
| RCC walls | 300 mm | 400 mm | 500 mm | 600 mm+ |
| RCC roof slab | 400 mm | 500 mm | 600 mm | 750 mm+ |
| Protection factor | 1,000+ | 2,000+ | 5,000+ | 10,000+ |
| Blast rating | 1 bar | 1 bar | 2 bar | 3 bar+ |
| Air system | Essential | Advanced | Advanced, twin | Elite |
| Power | Battery + generator | Battery + solar + generator | Twin generators | Microgrid |
| Stored water | 500 L | 1,500 L | 7,500 L | Borewell + storage |
| Decontamination | Wipe-down zone | Shower | Shower + changing | Full suite |
| Exits | Hatch | Hatch | Tunnel + hatch | Multiple |
| Build time | 4–6 months | 6–9 months | 9–14 months | 12–24 months |
Scroll the table sideways on a phone. See engineering for what these numbers mean.
Fallout radiation drops fast, then slowly. For every sevenfold increase in time, it falls tenfold.
Read the guide to the 7:10 rule| After detonation | Radiation level | Meaning |
|---|---|---|
| 1 hour | 100% | Be sealed inside |
| 7 hours | 10% | Still dangerous |
| 2 days | 1% | Minimum time sealed |
| 2 weeks | 0.1% | Short, measured trips out |
| 3 months | 0.01% | Recovery in most areas |
Prefabricated steel units are designed for one soil and one climate. India has dozens of soils, a monsoon, seismic zones and summers above 45°C.
Clay near a river and Deccan rock need different waterproofing and structure. We design from a soil and groundwater test.
An elderly parent on oxygen, young children or staff all change the layout, power and supplies.
A prefab unit arrives on a truck in daylight. A custom shelter is built as ordinary construction.
A reinforced, filtered room within a building for intrusions, linked to the shelter.
A vault for documents and valuables inside the protected envelope.
Clinical lighting, medicine storage and power for an oxygen concentrator.
Shielded receivers, licensed two-way radio and protected antennas.
Finished as a cellar, gym, library or storeroom.
An exit further away, concealed in a garden or outbuilding.
A shelter on remote land, such as a Himalayan valley, with long autonomy and road or helicopter access. Retreat shelters
Every part, its standard, service life and lead time. Components
Tell us how many people and where. We will recommend a class and explain the trade-offs.