Unrivalled Expertise in Rooflight Manufacture
As the leading independent manufacturer of rooflights in the United Kingdom, Xtralite has unrivalled expertise in roof penetration technology which the company has applied to automatic opening vents (AOVs). With the development of vertical AOV solutions for walls and the addition of louvred vents applicable to many parts of the external envelope, Xtralite’s Ventilation Division can now satisfy all natural ventilation requirements.
In addition to effective air flow when operational, AOVs when closed must resist weather penetration and provide appropriate thermal insulation—areas where Xtralite specialises. The Xtralite range includes louvred units (particularly suitable for high-level use), double units and 140° single units, as well as 90° single units for access purposes.
Providing the Complete Natural Ventilation Package
Natural ventilation AOV’s may be required for a variety of reasons, notably energy efficient environmental management or smoke control during fires. Certified control panels are required to operate vents to meet specific needs—either automatically or manually by building managers or the fire and rescue services. Xtralite works in partnership with leading specialists in control systems to provide a complete package of natural ventilation.
Smoke Control using Natural Ventilation in Fires
Smoke control using natural ventilation is a particularly effective means of protecting escaping occupants, those awaiting rescue and fire-fighters from the immediate dangers of fire and smoke. In principle, high-level outlet vents and low-level inlet vents open automatically in the event of a fire to allow cool air into the building with smoke and hot air to flow out. This improves the conditions for occupants to escape and fire-fighters to enter. In the absence of ventilation, smoke fills the room, being drawn back down from the ceiling by convection as temperatures rise, leading to potential—and particularly dangerous—‘flashover’.
The specific design of an effective and safe smoke ventilation system requires specialist involvement, perhaps by the mechanical and electrical consultant, and may well form part of a fire engineering solution.
Helping You Comply with Building Regulations
Guidance to building regulations includes specific use of smoke ventilation systems, as outlined overleaf. In England and Wales, Part B of the Building Regulations covers fire and the Approved Document (AD B) Volume 2 provides guidance applicable to flats and non-dwellings. The following national, regulatory guidelines have similar requirements: Section 2 of the Scottish Building Standards Agency Technical Handbooks 2007; Technical Booklet E of the Building Regulations (Northern Ireland); Technical Guidance Document B of the Government of Ireland Building Regulations 2006. AD B identifies a number of situations where AOVs provide natural ventilation are appropriate, including:
- Small single stair blocks of flats
- Common escape routes in larger blocks of flats
- Basement areas
- Enclosed car parks
- Vertical smoke shafts, as part of a smoke control design
An example of a vertical AOV system
