Guide to Conversion of Traditional Buildings

2.13 Fire and rescue service facilities

Standard 2.14

Every building must be designed and constructed in such a way that facilities are provided to assist fire-fighting or rescue operations.

2.14.1 Type of standard

Mandatory Standard

In the case of conversions, as specified in regulation 4, the building as converted shall meet the requirement of this standard (regulation 12, schedule 6).

2.14.2 Commentary

Sir Eyre Massey Shaw in his book, Fires and Fire Brigades in 1884 wrote: “A fireman, to be successful, must enter buildings; he must get in below, above, on every side, from opposite houses, over back walls, over side walls, through panels of doors, through windows, through loopholes, through skylights, through holes cut by himself in the gates, the walls, the roof; he must know how to reach the attic from the basement by ladders placed on half burned stairs, and the basement from the attic by rope made fast on a chimney. His whole success depends on his getting in and remaining there and he must always carry his appliances with him, as without them he is of no use”.

Whilst some of these techniques would be frowned upon by today’s fire-fighters, the general principles proposed by Shaw over a century ago are still valid today.

‘Offensive’ fire-fighting is carried out within a building, using entrance and exit doors, corridors and stairways, provided for the occupants’ day-to-day use. If the conditions inside are too dangerous, ‘defensive’ fire-fighting will be undertaken from outside a building.

Fighting fires in deep basements are potentially the most dangerous of all fires to fight offensively as they can place great demands on the physical capabilities of fire-fighters. Fire-fighters must descend into what may in effect become a chimney, as the hot smoke will rise up the staircase, making this type of fire particularly difficult to deal with.

In each of these circumstances additional integral measures are required in a building, both to protect fire-fighters and to reduce their burdens.

a) Fire-fighting mains

Fire-fighting water mains may be considered necessary to alleviate the need to run out large amounts of hose and manoeuvre it through a building. For safety reasons hose lines are always charged before being taken into a building on fire and a fully charged hose is very heavy and not very flexible. Permanently fixed mains therefore save time and labour. It should also be noted that such mains have the potential advantage of protecting a building from considerable damage, such as damage caused by burst hoses outside the room of fire origin. However, the main must be properly maintained and periodically inspected and tested.

Fire-fighting mains may be either:

• Rising
• Falling
• Horizontal.

If an automatic fire suppression system is installed in the building, no point on the storey should be more than 60m from the fire main outlet, measured along an unobstructed route for laying a fire hose. If the building is not fitted with an automatic fire suppression system, no point on the storey should be more than 45 m from the outlet.

In practice, fire-fighting mains are generally ‘dry’ or ‘wet’ fire mains installed in accordance with BS 9990:2006 (dry being mains filled by the fire and rescue service on arrival at an incident; ‘wet’ being mains permanently filled with water).

In larger historic buildings it is not uncommon to find dry riser fire-fighting mains, but the landing valves should be enclosed within a fire resisting lobby where a fire-fighting ‘bridgehead’ may be established. This is part of a building, usually the floor below the floor affected by fire (the floor above in the case of basements), from which fire-fighting teams can be safely committed to attack a fire.

In tall buildings (with topmost floor level more than 18m) or buildings with deep basements it is desirable to establish such bridgeheads within staircases and in these circumstances a ‘fire-fighting shaft’ is formed. Fire-fighting shafts must be well protected from the effects of any fire by being enclosed within a long (two hour minimum) fire resistance duration structure accessed via a self-closing medium fire resistance duration door (FD 60S); the stairwell being further protected by another short fire resistance duration door (FD 30S) thus creating a ‘fire-fighting lobby’.

In buildings with a top floor higher than 18 metres, or where a basement is deeper than 10 metres, this shaft should include a lift, specially designed and installed so that fire-fighters may safely use it for transportation of personnel and equipment. Historic buildings may already have what appears to be a suitable lift installed that has previously been accepted for fire and rescue service use. However, on closer examination it might not satisfy the current safety requirements contained within BS EN 81-72.

This is a standard which governs lifts for use by fire-fighters in emergency situations. A fire-fighters lift is defined as a lift installed primarily intended for passengers use which has additional protection, controls and signals, which enable it to be used under the direct control of the fire and rescue service.

Fire-fighting shafts are provided in larger buildings to help fire-fighters reach floors further away from a building’s main access point. They enable fire-fighting operations to start quickly and in comparative safety by providing a safe route from the point of entry to the floor where the fire has occurred.

BS EN 81 discusses safety rules for the construction and installation of lifts. BS EN 81-72 specifies the additional or deviating requirements to EN 81-20:2020 for new passenger and goods passenger lifts, which can be used for fire-fighting and evacuation purposes under fire-fighters’ control.

A fire-fighting bridgehead must be kept free from smoke so it is vitally important that there are facilities to ventilate any smoke that might seep into the fire-fighting shaft, particularly the stairwell, which will probably also be required as a means of escape. Furthermore, due to the difficulty of removing heat and smoke naturally from basements, mechanical extract systems may be necessary.

The purpose of fire ventilation, as distinct from normal ventilation, is threefold:

• to facilitate fire-fighting,
• to prevent the spread of fire,
• to reduce damage by heat and smoke.

It must be recognised however, that whilst a considerable amount of research has taken place in the field of fire and smoke ventilation, this is a very complex subject.

Traditional buildings typically contain a main internal staircase that is a central and important architectural feature. Rooms usually open directly on to unprotected landings in this arrangement. The construction of a fire-fighting stair (or fire-fighting shaft in taller buildings) designed to enclose such a staircase and comply with the recommendations of the standard has the potential to have a significant impact on the character of the building. This presents a significant challenge to designers to meet the requirements of the standard by other means.

Further guidance is contained BS 9999: 2017 Section 6 Access and facilities for firefighting.

2.14.3 Issues to be considered

Issue - Risks to historic / traditional buildings

1. Internal fire mains It can be challenging to install new mains without damaging the character of key historic spaces or their features.

2. Fire-fighting lobbies and shafts The creation of fire resisting enclosures to the required standard or the construction of lobbies may damage the character of key historic spaces or their features.

3. Fire-fighting lifts Upgrading existing lifts may prove uneconomic.

4. Ventilation of heat and smoke Providing openable windows or ventilators to fire-fighting staircases may have a negative impact on the external fabric and appearance of a traditional building.

2.14.4 Recommendations to meet the standard

Issues that should be considered when implementing this standard:

a) The fire and rescue service should be provided with the facility to release smoke and heat from a fire during fire-fighting and rescue operations. Ventilation should be provided in non-domestic buildings to every escape stair and fire-fighting lobby with:

• a ventilator of at least 1 m2 at the top of the stairs; or
• a ventilator of at least 0.5 m2 at each storey on an external wall; or
• ‘Smoke shafts protecting fire-fighting shafts; their performance and design’ BRE 2002.

In domestic buildings, ventilation should also be provided in protected lobbies, protected corridors and in all fire-fighting lobbies by:

• a ventilator of at least 1m2 at each storey on an external wall; or
• smoke shafts as described in the guidance to standard 2.9 (domestic buildings only); or
• smoke shafts protecting fire-fighting shafts: their performance and design’ BRE project report 79204, 2002.

A natural or mechanical smoke ventilation system may also be used with the agreement of the fire and rescue service.

Ventilators should be fitted with a simple handle or lock that can be operated by fire-fighters. If ventilators are not easily accessible, they should be operated by a mechanism positioned within the building at the fire and rescue service access point. In the case of an escape stair and a fire-fighting stair, a local control should also be provided at the topmost storey. This will allow fire-fighter flexibility in their operations.

To avoid significant damage to historic character, where it is not possible to alter or improve facilities to aid fire service access and to meet the needs of the standard, the introduction of the following measures may help to compensate for deficiencies:

a. automatic fire suppression may be utilised to compensate for poor facilities to aid fire-fighting access by reducing the intensity and spread of fire or even extinguishing it (if the fire is not shielded from the water droplets) so giving more time for the fire service to safely gain access to the fire.

b. additional fire compartmentation and/or increased periods of fire resistance may delay fire growth and spread and thereby provide opportunities for securing fire-fighting bridgeheads.

c. reduction in the quantity of combustible materials, combined with good site management in accordance with BS 9999: 2017 Section 9, may compensate for poor facilities for ventilating fire compartments.