What does a fire compartmentation survey involve?

A fire compartmentation survey is a detailed inspection of the building's fire-resisting construction. It typically involves visual inspection of fire doors and their ironmongery, inspection of fire stopping around service penetrations through compartment walls and floors, inspection above suspended ceilings and within risers to check the continuity of compartment walls, assessment of cavity barriers in concealed spaces, and checking that fire-resisting construction has not been breached by subsequent alterations or maintenance. The survey may include invasive inspection (lifting ceiling tiles, opening inspection hatches) to check concealed areas.

What are the most common compartmentation deficiencies?

The most common deficiencies found in London buildings include missing or inadequate fire stopping around service penetrations (pipes, cables, ducts) through compartment walls and floors, fire doors that do not close properly, have missing intumescent strips or cold smoke seals, or have been damaged, gaps at the junction between compartment walls and the underside of the floor slab above (particularly above suspended ceilings), missing cavity barriers in roof voids and facade cavities, and breaches in compartment walls caused by subsequent building works or tenant alterations.

How much does fire compartmentation remediation cost?

Costs vary significantly depending on the size of the building, the extent of the deficiencies and the difficulty of access. Fire stopping remediation for a typical residential block might cost £10,000 to £50,000. Fire door replacement for a block with 50 to 100 doors can cost £75,000 to £200,000 depending on the door specification. Major remediation involving opening up concealed areas, reinstating cavity barriers and repairing compartment walls can cost significantly more. The survey report should prioritise the deficiencies by risk, allowing the building owner to plan remediation in a structured and cost-effective way.

What to Expect from a Fire Compartmentation Survey | Hampstead Chartered Surveyors & Building Consultancy

Q: What is fire compartmentation?

Fire compartmentation is the subdivision of a building into compartments using fire-resisting construction (walls, floors and doors) to prevent the spread of fire and smoke from the compartment of origin to other parts of the building. In a residential block of flats, each flat should be a separate fire compartment, and the common escape routes should be protected by fire-resisting construction. Compartmentation is fundamental to the 'stay put' strategy relied upon in most purpose-built blocks.

Overview

Why compartmentation matters

Fire compartmentation is the primary passive fire protection measure in residential blocks of flats. It prevents fire and smoke spreading from the flat of origin to other parts of the building, supporting the stay-put strategy that most purpose-built blocks rely upon. Deficiencies in compartmentation are common and can have serious life-safety implications.

The survey process

A compartmentation survey involves a detailed inspection of all fire-resisting construction: compartment walls and floors, fire doors, fire stopping at service penetrations, cavity barriers in concealed spaces, and the integrity of the protected escape routes. The survey typically includes invasive inspection, lifting ceiling tiles and opening hatches to check concealed areas where deficiencies are most commonly found.

Common deficiencies

The most frequent findings include missing or inadequate fire stopping around pipes, cables and ducts passing through compartment walls and floors; fire doors that fail to close properly, have missing seals or damaged glazing; gaps above suspended ceilings where compartment walls do not extend to the structural soffit; missing cavity barriers in roof voids; and breaches caused by subsequent building works or tenant alterations.

Remediation

Remediation is prioritised by risk and typically involves installing or replacing fire stopping, replacing non-compliant fire doors, extending compartment walls to full height, installing cavity barriers, and repairing breaches. The survey report provides a prioritised schedule of works that allows the building owner to plan remediation in a structured way.

FAQ

Frequently asked questions

What is fire compartmentation?

The subdivision of a building into compartments using fire-resisting walls, floors and doors to prevent fire and smoke spreading. Fundamental to the stay-put strategy in residential blocks.

What does a compartmentation survey involve?

Detailed inspection of fire doors, fire stopping, compartment walls and floors, cavity barriers and concealed spaces, typically including invasive inspection above ceilings and within risers.

What are the most common deficiencies?

Missing fire stopping around service penetrations, non-compliant fire doors, gaps above suspended ceilings, missing cavity barriers and breaches from subsequent works.

How much does remediation cost?

Fire stopping: £10,000 to £50,000. Fire door replacement: £75,000 to £200,000 for a typical block. Costs vary by building size and extent of deficiencies.

Next Steps

What to Expect from a Fire Compartmentation Survey