Natural Ventilation and Smoke Ventilation Standards
25 March 2011
This was one common theme brought up at a recent CAB (Council for Aluminium in Building) breakfast meeting between facade companies and key contractor speakers from the industry. Following these implications, contractors were willing to keep to the tender of the initial specialist supplier, as long as prices for the product/installation remained competitive. Falling price pressures aside, this seems to be a significant turnaround from what is currently perceived as contracting for building works at the lowest possible price.
One area of rapid change in all our buildings today is that of natural ventilation and smoke ventilation. Both these systems are often combined to provide a cost effective, safe and sustainable solution for our new and existing buildings.
Adaptive natural ventilation methodologies and standards
Looking at the regulations covering both these areas separately, adaptive natural ventilation methodologies help to keep buildings pleasant places to be with the minimum of energy input. Consequently, design guides and building regulations are referred to in the specification of these systems.
Often opening windows in facades and roof lights, operated by window actuators, adaptive natural ventilation strategies can prove to be sustainable and economical to run compared to other forms of cooling and ventilation.
Approved Document F 2006 ‘Means of Ventilation’ covers the compliance side of the design requirements suggesting minimum ventilation requirements that need to be supplied. Approved Document L2A and L2B 2006 ‘Conservation of fuel and power in new buildings other than dwellings’ also need to be consulted regarding energy efficiency of any installed systems.
Designing to meet the stringent BREEAM (Building Research Establishment Environmental Assessment Method) energy savings, reward points can be given to adopting adaptive natural ventilation systems, BRE 290 ‘Ventilation and cooling option appraisal’ offers a client’s guide to what can be achieved. CIBSE (Chartered Institution of Building Services Engineers) also promotes ventilation best practice in their guide, AM10. BSRIA (Building Services Research and Information Association) offers a guide on Night cooling strategies. And there are many other guides which suggest various methodologies which have been successfully adopted.
Specifically in education, design guide BB101 (Building Bulletins) recommends natural ventilation in teaching spaces. There are various Building Bulletins produced by the Department for Children, Schools & Families on all aspects of school design.
In order to become a specialist in the area of adaptive natural ventilation, and to keep up to speed on the rapid development taking place, a great deal of on-going study is required. As mentioned earlier, this is where a specialist in adaptive natural ventilation should be consulted.
Similar solutions toadaptive natural ventilation are used when we look at smoke control systems, with some main differences. As in adaptive natural ventilation,smoke ventilation often uses windows in facades and roof lights, however, control systems need to be independent of the buildings power supply. Often running on a battery back-up 24 volt system,smoke ventilation provision should be fully operational when there is a power outage.
Smoke control systems also form part of a legal provision of fire safety from building owners. Preventative maintenance of these systems is crucial to ensure that smoke ventilation takes place when required and to ensure people in the building have a safe passage of exit. Badly maintained systems are the responsibility of the building owners and prosecutions are on the increase.
Sometimes referred to as SHEVS (Smoke and Heat Exhaust Ventilation) smoke control can be designed to use the rising warm air from combustion by offering an exhaust at high level (roof vent) and provision at lower levels (opening windows) to allow fresh air in. In more complex situations fan assistance is required to assist smoke evacuation.
Standards are much more complex in the area of smoke control, CIBSE Guide E 1997 offers guidance on heating, venting, air conditioning and refrigeration. EN12101 ‘Smoke and heat control systems’ consists of 10 parts which offers guidance and calculation methods for the evacuation of smoke. There are also various British Standards and BRE design guides that offer design methodologies to correctly identify and make provision for smoke control systems.
Adaptive natural ventilation and smoke controlare often integrated in today’s modern buildings. This offers a significant saving on installation and maintenance costs. These issues can again be discussed at early design stages in order to maximise cost savings on designs.
Smoke control systems and Adaptive natural ventilation systems can operate as an independent standalone system or can be linked into the building management system... Newer systems are now becoming more intelligent and offer intelligent feedback of opening and closing operations so that equipment failures often caused by obstructions, can be identified and repaired at scheduled planned preventative maintenance visits, to ensure even higher levels of safety provision.
For more information on standards covering various building uses, refer to the SE Controls website or contact SE Controls for an early design consultation. SE Controls are actively involved in government sponsored working groups and are able to share this developing knowledge base with clients.
SE Controls operate across the globe with offices in several continents, with specialists offering clients expert advice based on local legislative requirements.
Smoke Ventilation Solutions, brochure
Natural Ventilation for Education Buildings, brochure
Smoke Ventilation, Natural Ventilation and Window Automation, brochure