Decide the room's job: storm shelter, intrusion safe room, secure store, or all three
A storm shelter, a room to retreat to during a break-in and a locked store for valuables have different design rules. Decide which jobs the room must do before anyone draws it, because a combined room must meet the strictest rule for each job.
How
- List your hazards from the estate hazard register: tornado, hurricane or cyclone, wildfire, burglary or intrusion, theft while the house is empty.
- Storm or tornado shelter: in the US, FEMA P-320 (homes and small businesses) and FEMA P-361 (community and residential safe rooms) give design guidance, and the ICC 500 standard sets construction rules that US building codes reference. Other countries have different rules or none, so check what your national code says.
- Intrusion safe room: the aim is to delay entry long enough to call for help or for an attacker to give up. This drives door, lock and wall strength and a way to communicate from inside.
- Secure store: the aim is protecting money, documents, precious metals, medicines and any legally held firearms from theft, fire and damp. This drives safe ratings, anchoring and humidity control rather than room size.
- If you want one combined room, write down that it must meet storm-shelter structure rules, intrusion delay, and secure-storage needs at the same time, and that people may be inside it for hours.
- Write a one-page brief: the jobs, how many people, how long they may stay inside, and what will be stored.
Do these first
Sources
- FEMA P-320 Taking Shelter from the Storm: Building a Safe Room for Your Home or Small Business (6th ed., 2nd issuance). US Federal Emergency Management Agency (FEMA), accessed 2026-11
- FEMA P-361 Safe Rooms for Tornadoes and Hurricanes: Guidance for Community and Residential Safe Rooms. US Government Publishing Office / FEMA, accessed 2026-11
- ICC 500: Standard for the Design and Construction of Storm Shelters (summary of the 2014 edition). Ready.gov / FEMA, accessed 2026-11
- Safe Rooms and Storm Shelters (Building America Solution Center). US DOE / Pacific Northwest National Laboratory, accessed 2026-11