A mamad is not a reinforced room. It is a closed system judged as a whole: structure, openings and ventilation. If one of the three does not meet the specification, the room is not a mamad — even if it is built of concrete and even if it looks exactly like the neighbour's.
Important note: the specification is updated, and requirements vary with the year of the permit, the building type and the risk zone. The figures here are a guide for planning and budgeting — the binding version is the one published by the Home Front Command and approved by the local authority's engineer for your file.
Structure
- Cast-in-place reinforced concrete. Not blockwork, not plasterboard, not modular. The mamad walls are part of one continuous system, so they are poured together with their own slab.
- Wall thickness — around 25 cm, and a ceiling around 20 cm, per the specification applying to the project.
- Dense reinforcement to the engineer's drawing, including anchoring to the floor and to the structure. See structural engineering.
- No drilling, chasing or breaking through the mamad walls. This is the point most often damaged during renovations, and it voids the protection in practice.
Area and dimensions
A residential mamad in a new apartment building requires a net area of about 9 m². In older mamadim you will find 5 to 6 m² per the specification in force at the time. The height must match a normal habitable room. The area is measured net, between wall faces — and this is the common planning error: nine square metres are planned gross, and the room comes up short.
The openings
Blast door
An approved steel door, certified and marked by its manufacturer, opening outwards from the mamad. The direction is not arbitrary: it is what allows you out even if something has collapsed on the other side. The door is fitted into a cast, anchored frame — not one added afterwards.
Blast window
A sealed steel window with a blast shutter, in an approved size and position. It provides ventilation and daylight in normal times and is sealed in an emergency. Replacing the mamad window with an ordinary aluminium one — however much better it looks — voids the approval.
The only opening you may add
Beyond the door, the window and the approved service penetrations, none. Any additional penetration requires an engineer's approval.
Ventilation and filtration
The mamad includes a ventilation and filtration system with dedicated inlet and outlet openings and a place prepared for a filter. The system requires periodic inspection — and in a large share of the flats we enter it has never been checked since handover. It is the most neglected maintenance item there is.
Electrics and services
- Power and lighting points on a separate supply, per the approved drawing.
- A data point and mobile reception — in a concrete mamad, reception is a genuine problem worth planning for. See smart home infrastructure.
- No unapproved pipework or cabling may pass through the mamad walls.
Five clauses that fail inspection
- A hole drilled in a wall for a shelf, a television or an air conditioner. The most common by far.
- A replaced door, or one whose opening direction was changed.
- A missing or non-functioning filtration system.
- Net area below the requirement — usually the result of cladding or a stud wall added inside.
- A service penetration broken through afterwards for air-conditioning pipework.
How to live in the room without damaging it — safe room design.
FAQ
Can a shelf be fixed to a mamad wall?
Not by drilling into the reinforced concrete. Drill-free solutions, or freestanding furniture bearing on the floor, are the right approach.
Can air conditioning be installed?
Yes, but only through an approved service penetration and with an engineer's approval. Breaking through a wall yourself voids the protection.
How do I know which specification applies to me?
By the building's permit. Request the file from the local planning committee — the approved mamad drawing is in there too. See building permit.
How we work
Bramy Group builds safe rooms as part of envelope works and building additions, to an engineer's drawing and in coordination with the planning committee. See also building a safe room. Get in touch.