Car vaults: secure, climate-controlled storage for a collection

Why collectors bring the cars home

A collection often outgrows the house garage. The usual answers are off-site storage, a collector garage unit, or a vault at home.

Collectors already pay heavily for dedicated space. In Scottsdale, Arizona, whole developments of private collector garages are being built. A vault at home gives the same security, with the cars a short walk away.

Security

Security starts with being hard to find. A vault below ground has no windows, and a flush lid or a pavilion shows little from outside.

Inside, the layers are access control, monitored alarms and CCTV. One private London car park, bought to hold a large fleet, used numberplate recognition and full CCTV. Chubb advises restricting access to trusted and vetted individuals.

Fire

Chubb's guidance asks for upgraded wiring, minimal combustibles and fire detection connected to a central alarm station. A room below ground also needs a smoke strategy and a safe way out for people.

Electric and hybrid cars bring battery fire risk into the design. We agree the fire strategy for each project with a fire engineer and, where possible, with the insurer before the build.

Humidity and climate

Damp harms metal, leather and electrics, and a sealed room below ground needs its air managed. A BELOW vault is designed with mechanical ventilation, humidity control and monitoring, so conditions stay steady through the seasons.

Waterproofing comes first. A room that lets water in cannot be kept dry by machines alone, so the structure is designed to stay dry on its own.

What insurers expect

Insurers treat storage as part of the risk. Chubb's published guidance for collector cars asks for:

• a secure, enclosed garage with locks
• access restricted to trusted and vetted individuals
• upgraded wiring
• no clutter of combustible materials
• fire detection connected to a central alarm station

Insurers also send loss-prevention specialists to inspect valuable collections. Chubb's specialists use infrared thermography to find overheating wiring and leaks, and assess alarms and flood or fire exposure. Aviva published its own safe-storage guide for classic and high-end cars in September 2025.

Designing to these points from the start is simpler than adding them later. We suggest your insurer reviews the specification before the build begins.

Lit as a gallery

Super-prime homes already market basement car rooms with showroom lighting, and with turntables to show cars from different angles.

BELOW lights each gallery for the cars it holds, with light lines, display lighting and finishes chosen with the house. A turntable can present one car at a time. A lounge or a bar can sit at the end of the aisle.

Passion first

Classic cars are a passion asset as much as a financial one. Knight Frank reports that classic car values were soft in 2025, yet demand for the right car stayed strong at auction.

The case for a vault is protection and enjoyment, not a return. Our underground garage cost guide explains what drives the budget, and our residential car lift guide explains how the cars get in and out.