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The primary function of smoke control is to save lives. But as more emphasis is being put on sustainable buildings, natural venting systems are coming into play.
The environmental impact of all elements of modern building projects is increasingly being taken into account and in some instances, the most sustainable solution is also the safest one.
At Westfield Derby shopping centre, a smoke control system has been installed to provide, wherever possible, a sustainable solution that doesn’t scrimp on safety. The centre is part of a GB pound 2bn regeneration project to the city centre, incorporating up to 5000 new homes, commercial property, retail, tourism and leisure development, supported by an improved infrastructure.
Opened in October last year, Westfield Derby is one of the UK’s largest retail developments. The shopping centre has brought more than 150 new stores into the city centre following GB pound 340m of construction work. The centre was first built in the 1970s and re-developed in 1990, when Colt International installed the original mall and smoke ventilation system, incorporating mechanical extraction plant, glazed ventilators and drop down smoke curtains, controlled by an ‘intelligent’ EN OPV (One Per Vent) system.
Upgrade
The new scheme – the installation of which began in 2007 – was upgraded to meet the demands of the substantially increased size and expanded role of the centre. Despite being officially re-opened at the end of 2007, the smoke control modernisation continued into the summer of 2008, with installation being carried out around an operational shopping centre.
Older equipment was upgraded, additional technologies installed and a fully functioning smoke vent system implemented, using natural ventilation wherever possible to minimise energy use. Throughout the work, the smoke control system remained fully functional.
Natural ventilation provides the most sustainable smoke control solution, as no electricity is required to power it. It is also the most effective form of smoke control, as it relies on the natural forces of buoyancy and wind pressure differences to create air circulation without external power. So it is self-regulating rather than working to a fixed extract rate. This means that, if part of a designed scheme, it can actually provide more effective control of smoke than mechanical extraction – if there is more buoyancy in the smoke, the vents will allow more of it to be extracted.
In addition, natural ventilators are dual-purpose, providing day-to-day ventilation as well as smoke control. As the chances of fire are minimal, using dual-purpose equipment is an efficient use of resources, whereas mechanical extract systems remain redundant until they are required to remove smoke.
Exception
Originally, the smoke ventilation scheme was designed to be completely natural, until the addition of a multi-level cinema next to the flat roofed food court. The height of the cinema complex affects the wind over-pressures: as natural ventilation relies on buoyancy, if the wind hits the building it goes downwards instead of up and over, so mechanical extraction is required to transport smoke in the event of a fire. Natural ventilation is ideal for single storey buildings but with multi-storey ones, smoke has to be ducted out.
Smoke control for the main areas of the mall consists of natural ventilation, in the shape of EN Seefire louvred ventilators and Kameleon natural casement ventilators. In the lobbies and staircases, a natural BRE shaft, including defender dampers and EN Seefire terminations, has been installed. The system is integrated with the centre’s fire alarm and sprinkler system, the latter of which features quick response sprinkler heads and is installed throughout the centre – other than in the car park and high ceiling areas in the mall. The system was designed in conjunction with the consultants on the project, JGA Fire Engineering.
Intreconnected automatic fire detection is also installed in all areas of the centre other than in the car park. In an emergency, occupants are alerted by voice alarm in the mall areas and by sounders in the rest of the centre. Much of Westfield Derby is monitored by a CCTV system, which helps the centre’s management with evacuation and provides valuable information for firefighters on their arrival.
EN Seefire is a natural louvred ventilator suited to most industrial and commercial buildings to provide both day-to-day and smoke ventilation. Popular with specifiers and contractors due to the range of options available, and with building operators and owners because of their simplicity and low maintenance, louvred ventilators are also one of the most cost-effective kinds of natural ventilator. The louvres of these units can provide the entry of natural daylight, further reducing lighting loads and minimising the need for artificial light. Kameleon is a natural casement ventilator that can be installed into glazing or other types of walling systems.
Colt’s intelligent control system allows the dual function of day to day control of internal temperatures and smoke control, providing addressability, monitoring and diagnostics, with low maintenance and minimal power requirements. At Westfield Derby it removed the need for much of the hard wiring and enabled integration of all equipment, thereby assisting in the energy efficiency of all systems.
Phill Terry, a senior consultant for Colt, sums it up: “Colt advocates the use of natural ventilation systems wherever the design allows these to be applied. In addition to being more sustainable, the primary driver in our approach has been that these provide the most effective and cost-effective form of smoke control. Why over-complicate things when a more simple approach provides the best results?”
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The primary function of smoke control is to save lives. But as more emphasis is being put on sustainable buildings, natural venting systems are coming into play.
The environmental impact of all elements of modern building projects is increasingly being taken into account and in some instances, the most sustainable solution is also the safest one.
At Westfield Derby shopping centre, a smoke control system has been installed to provide, wherever possible, a sustainable solution that doesn’t scrimp on safety. The centre is part of a £2bn regeneration project to the city centre, incorporating up to 5000 new homes, commercial property, retail, tourism and leisure development, supported by an improved infrastructure.
Opened in October last year, Westfield Derby is one of the UK’s largest retail developments. The shopping centre has brought more than 150 new stores into the city centre following £340m of construction work. The centre was first built in the 1970s and re-developed in 1990, when Colt International installed the original mall and smoke ventilation system, incorporating mechanical extraction plant, glazed ventilators and drop down smoke curtains, controlled by an ‘intelligent’ EN OPV (One Per Vent) system.
Upgrade
The new scheme – the installation of which began in 2007 – was upgraded to meet the demands of the substantially increased size and expanded role of the centre. Despite being officially re-opened at the end of 2007, the smoke control modernisation continued into the summer of 2008, with installation being carried out around an operational shopping centre.
Older equipment was upgraded, additional technologies installed and a fully functioning smoke vent system implemented, using natural ventilation wherever possible to minimise energy use. Throughout the work, the smoke control system remained fully functional.
Natural ventilation provides the most sustainable smoke control solution, as no electricity is required to power it. It is also the most effective form of smoke control, as it relies on the natural forces of buoyancy and wind pressure differences to create air circulation without external power. So it is self-regulating rather than working to a fixed extract rate. This means that, if part of a designed scheme, it can actually provide more effective control of smoke than mechanical extraction – if there is more buoyancy in the smoke, the vents will allow more of it to be extracted.
In addition, natural ventilators are dual-purpose, providing day-to-day ventilation as well as smoke control. As the chances of fire are minimal, using dual-purpose equipment is an efficient use of resources, whereas mechanical extract systems remain redundant until they are required to remove smoke.
Exception
Originally, the smoke ventilation scheme was designed to be completely natural, until the addition of a multi-level cinema next to the flat roofed food court. The height of the cinema complex affects the wind over-pressures: as natural ventilation relies on buoyancy, if the wind hits the building it goes downwards instead of up and over, so mechanical extraction is required to transport smoke in the event of a fire. Natural ventilation is ideal for single storey buildings but with multi-storey ones, smoke has to be ducted out.
Smoke control for the main areas of the mall consists of natural ventilation, in the shape of EN Seefire louvred ventilators and Kameleon natural casement ventilators. In the lobbies and staircases, a natural BRE shaft, including defender dampers and EN Seefire terminations, has been installed. The system is integrated with the centre’s fire alarm and sprinkler system, the latter of which features quick response sprinkler heads and is installed throughout the centre – other than in the car park and high ceiling areas in the mall. The system was designed in conjunction with the consultants on the project, JGA Fire Engineering.
Intreconnected automatic fire detection is also installed in all areas of the centre other than in the car park. In an emergency, occupants are alerted by voice alarm in the mall areas and by sounders in the rest of the centre. Much of Westfield Derby is monitored by a CCTV system, which helps the centre’s management with evacuation and provides valuable information for firefighters on their arrival.
EN Seefire is a natural louvred ventilator suited to most industrial and commercial buildings to provide both day-to-day and smoke ventilation. Popular with specifiers and contractors due to the range of options available, and with building operators and owners because of their simplicity and low maintenance, louvred ventilators are also one of the most cost-effective kinds of natural ventilator. The louvres of these units can provide the entry of natural daylight, further reducing lighting loads and minimising the need for artificial light. Kameleon is a natural casement ventilator that can be installed into glazing or other types of walling systems.
Colt’s intelligent control system allows the dual function of day to day control of internal temperatures and smoke control, providing addressability, monitoring and diagnostics, with low maintenance and minimal power requirements. At Westfield Derby it removed the need for much of the hard wiring and enabled integration of all equipment, thereby assisting in the energy efficiency of all systems.
Phill Terry, a senior consultant for Colt, sums it up: "Colt advocates the use of natural ventilation systems wherever the design allows these to be applied. In addition to being more sustainable, the primary driver in our approach has been that these provide the most effective and cost-effective form of smoke control. Why over-complicate things when a more simple approach provides the best results?"