Protective Shelter Retrofitting

Retrofitting Existing Buildings with a Protective Shelter

Protective shelter retrofitting enables an existing room – typically a basement room – to be converted into a fully functional and secure protective shelter. The existing building structure is specifically upgraded and supplemented with modern protective technology to create a reliable retreat location for crisis and emergency situations.

This solution is particularly suitable for owners of existing buildings where a protective shelter was not included during the original construction.

Protection Levels and Possible Applications

Depending on the configuration, a retrofitted protective shelter can provide protection against:

• Nuclear, biological, and chemical (NBC) hazards

• Radioactive contamination

• Fire exposure and smoke gases

• Explosions and pressure waves

• Break-ins, violent attacks, terrorism, and civil unrest

• Natural disasters and industrial or power plant accidents

Structural Requirements and Recommended Rooms

For professional retrofitting, the following basic requirements apply:

• Location preferably in a corner of the building

• No or only minimal openings to the outside

• Recommended room size: 15–30 m²

• Clear room height of at least 1.95 m

• No chimney, gas, or heating pipe penetrations

• No fire or explosion hazards in the immediate vicinity

Existing professionally constructed masonry and load-bearing interior plaster can generally remain in place. If required, existing walls can be additionally reinforced.

Construction and Structural Requirements

• Ceilings above the protective shelter including screed: minimum 15 cm thickness

• Exterior walls below ground level: ≥ 350 kg/m²

• Exterior walls above ground level: ≥ 1,000 kg/m²

• Interior walls adjacent to openings: ≥ 750 kg/m²

• Basement windows in the shelter area can be bricked up or fitted with a custom-made hatch upon request.

• The basement window can serve as an emergency exit.

NBC Air Filtration and Pressure System

A key element of protective shelter retrofitting is the controlled air supply system:

• NBC gas filtration system

• Filtration of nuclear, biological, and chemical contaminants

• Creation of controlled positive pressure inside the shelter

• Explosion protection valves and gas flaps for pressure regulation

This ensures a reliable supply of breathable air even when the outside air is contaminated.

Standard Safety Equipment

• Robust pressure door or armored door

• Emergency exit (structurally defined via window or door)

• NBC gas filtration system

• Explosion protection valves / gas flaps

• Dry toilet

Usage Concept

The protective shelter is designed for multiple uses:

• Everyday use, for example as storage or technical space

• Emergency use during crises and disasters as a protected sanctuary area

You can get an insight into the construction and equipment concept in our video: https://www.youtube.com/shorts/o7F3MNg7zQ4

Planning and Implementation

Before implementation, our specialists assess:

• Existing structural conditions

• Static requirements

• Load-bearing capacity of walls and ceilings

• Technical feasibility

Planning is always carried out individually and specifically for each property to ensure a safe, standards-compliant, and technically reliable retrofit solution.