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Ventilation Information

Ventilation Overview

Extraction fans and ventilation ductwork sit at the core of commercial ventilation. Kitchen extract fans and bathroom extractors are the most popular items in domestic ventilation. Natural ventilation and trickle ventilation are areas of increasing interest within the construction industry as energy conservation and sustainability move to the forefront of design considerations....more


Featured Ventilation Companies (3 of 6)

  • Gebhardt is a leading European fan manufacturer producing smoke, duct and contemporary roof extraction fans for heating and ventilating and air...

  • Vortice is a European market leader in ventilation, air conditioning, air cleaning and heating systems. In recent years our product development has...

  • GDL Air Systems manufacture and supply air distribution products. Our main product lines are grilles and diffusers, louvers, dampers, solar shading and...


Ventilation Explained

Ventilation is an important consideration within any new or existing building. A wide selection of ventilation equipment is available to suit virtually every ventilation requirement within residential, commercial and industrial buildings.

Key areas within residential buildings, such as houses and flats, that require adequate ventilation to satisfy building regulations and prevent the accumulation of condensation and mould growth are bathrooms and kitchens. Within bathrooms standard ventilation equipment comprises small volume extractor fans which are usually ceiling mounted. The extractor fans require accompanying ductwork, which is routed to the exterior of the house, through which the air is extracted. Bathroom extractor fans can be linked to cord pull light switches to allow there operation. More sophisticated bathroom extractor fans utilise humidity sensors to ensure that they only extract when it is absolutely necessary. Humidity sensor fans have the advantage of saving electricity. Within new builds extractor fans can be installed to fit virtually flush with the wall or ceiling profile and their rotors are protected by plastic grilles.

Another major area requiring ventilation within the residential environment is the kitchen. Cooking fumes and associated particles need to be expelled to the exterior of the building to avoid internal air contamination. Kitchen hoods fitted with an extractor fan, often referred to as an extractor hood, are an ideal way of extracting contaminated air at source. Kitchen hoods can be purchased separately from cooker manufacturers or specialist companies in a variety of finishes from modern stainless steel to more traditional wood clad hoods to blend in with existing fitted kitchen units.

In response to the need to make new homes more energy efficient, in order to reduce carbon dioxide emissions, new ventilation systems have been developed for residential buildings that minimise heat loss from the building, whilst providing adequate ventilation. New ventilation concepts are typically based around mechanical ventilation. Variants include mechanical ventilation with heat recovery (MVHR) that utilises a central extraction unit in to which extraction ducting runs from bathroom areas, or other wet rooms, and kitchen areas. Contaminated or humid air is then expelled to the exterior of the building and gives up its heat to fresh air drawn in from outside. The fresh air is then ducted to other rooms to prevent air from stagnating within the building. Mechanical ventilation systems are sometimes referred to as whole house ventilation systems. Other mechanical ventilation systems include central mechanical extract (CME) systems where a central extractor fan draws contaminated air in from kitchen and bathroom areas via ducting, which then expels the air to the exterior. Fresh air enters the property via window trickle vents to aerate the property. The extractor units run continuously and the systems are generically referred to as continuous ventilation systems.

Non powered ventilation techniques include passive stack ventilation (PSV) installations. Passive stack ventilation systems utilise near vertical ventilation ductwork known as 'stacks'. The inlets to the stacks are located in wet rooms, bathrooms and kitchens. Hot humid air naturally rises and enters the stack inlet and rises into the atmosphere outside the building. The motion of the wind and natural weather pressure differentials further aid the flow of internal air from the stack outlet. Stack outlets are often hidden under ridge tiles or cowls on the roof. A refinement of the passive ventilation system is controlled passive ventilation which utilises humidity sensing valves which open the stack only when humidity levels are high and ventilation is necessary. Controlled passive ventilation does not require an electricity supply.

Where older properties with poorly performing insulation or no insulation to external walls have internal damp problems dehumidifiers may prove to be the only way of keeping internal moisture levels at acceptable levels. Dehumidifiers may also prove essential when drying out flooded properties. Where moisture is a permanent problem wall mounted dehumidifiers are likely to represent the best choice, however if required on a temporary basis portable dehumidifiers are versatile and can be wheeled from room to room.

Within commercial and public buildings roof ventilation systems are often used to provide adequate ventilation and light. Typical systems include roof and skylights which can be sensor controlled to open and close automatically to maintain indoor temperatures and prevent rain ingress. More traditional systems on residential buildings are designed for roof void ventilation. Roof void ventilation products include vent tiles, often known as vent slates, manufactured from either clay or coloured plastic to blend in with roof tile colours. Other roofing vents include ridge tile vents, facia vents and eave vents which all allow the flow of air in to the roof void to prevent mould and condensation build up. Electric roof ventilation products include roof axial fans housed in covered vents and are suitable for flat roofs.

Industrial building ventilation systems are a large product area and are often designed to suit specific requirements and building functions. Industrial ventilation specialists will be able to design and advise on the best ventilation specifications. Industrial fans will often be required to remove contaminated air or exhaust fumes from processing or warehouse areas to maintain a safe working environment. Many industrial fans are of the axial type to enable in line linking with ventilation ducting. Other industrial extractor units include circular duct fans and centrifugal fans. A number of special 'smoke fans' can be purchased to withstand the extraction of hot air from processing areas. Specialist bespoke ventilation units can be constructed to perform specific functions.