Since time immemorial humans have looked at different types of ventilation systems. And they have done so as a means of cooling themselves down – but in a way that doesn’t pollute their internal environment.
Earlier architects looked at designing open court yards, U-shaped floor plans and large windows in a bid to accommodate desires for a consistent flow of fresh air when needed.
The reason we need ventilation in buildings is because it replaces the stale air we breathe in with fresh air. This means our bodies aren’t taking in bacteria and carbon, which in time can negatively affect our respiratory system, and make us ill. And, of course, ventilation can also rid our internal environment of nasty smells – a good enough reason in itself!
Regardless of the types of ventilation systems available in the UK today, the purpose is always the same. And that is to provide a building with healthy air by diluting toxins currently in the atmosphere, and, at the same time, remove them from inside to outdoors.
The ventilation system achieves this by bringing in outside air and distributing it. There are various different elements involved when creating a ventilation system. This includes the amount of air from outdoors that will be brought in, its quality, what direction the air will flow in, and how it will flow ie the pattern of air movement.
There are three main types of ventilation systems – natural, mechanical and hybrid.
Natural ventilation systems
This type of ventilation system utilises openings in the fabric of the building itself, such as windows, doors, chimneys and trickle vents in windows to allow air inside and then extract out. This is controlled by the weather (ie wind) and external temperature as well as human nature ie if someone opens a window or door.
If this is the route you intend to go down for your home or commercial premises then it’s necessary to plan all this during the initial design stage of the building and certainly prior to construction beginning.
Wind driven ventilation – if the ventilation is driven by wind then high pressure can be put on the windward side of the building and low pressure on its leeward side. The areas of high pressure then encourage the wind to flow down to the low-pressure areas.
Stack effect ventilation – hot air is lighter than cold air so it will flow upwards into rooms higher than ground level. That’s providing the openings are there in the first place to let it get through. Lower floors in a building will always be me more likely to have cooler air.
Benefits of natural ventilation
• It’s less expensive than other forms of ventilation
• It doesn’t require as much maintenance as, for example, mechanical ventilation systems
Negatives of natural ventilation
• Initial design can prove complicated
• Not great for areas where there is a lot of pollution, and noise
It needs wind or human intervention to work ie for the air ducts to be kept open
Mechanical ventilation systems
These are often used to control both the air quality and the temperature of a building, with fans bringing in air via the supply ventilation system and then expelling it via an exhaust ventilation system. Fans tend to be installed in windows, walls or air ducts of ventilation systems.
Often heating elements, such as hot water coils and air conditioning heat pumps or dehumidifiers are deployed, along with filters and heat exchangers.
Benefits of mechanical ventilation
• It is very adaptable ie it can work in most conditions, regardless of what the external environment is like
• It often provides very consistent air pressure and temperature
• Today’s systems can be very energy efficient
Negatives of mechanical ventilation
• It can prove expensive to run
• Uses a lot of energy
• Can spread infection quickly if not installed properly in the first place
Hybrid ventilation systems
A hybrid ventilation model – or ‘mixed-mode’ system – makes use of the best bits of both natural and mechanical types of ventilation systems. It can use either natural or mechanical ventilation depending on what it needed, and when. For instance, in the winter it may be that only the natural ventilation system is needed since the temperature has fallen by then anyhow.
The mechanical ventilation part can also be used if there isn’t enough wind, making the natural ventilation supply too low. In recent years, instead of ceiling fans, engineers have been installing wind turbines (also known as whirlybirds) on roofs as an additional exhaust system to increase airflow in a building.
Hybrid systems are usually one of two kinds – contingency or complementary.
Contingency – this type of system tends to be more common in older buildings. It’s when natural ventilation is the basic form, with mechanical ventilation added when it’s either too hot or cold.
Complementary – this is when both types of ventilation system work together as one ie as an integrated unit. The natural ventilation system is helped to operate by mechanical ventilation to maintain the temperature when the external environment is too hot or cold.
Hybrid ventilation is good for only using energy when necessary, meaning the costs of running it are low compared to full mechanical ventilation systems. Better still, the cost of the hybrid ventilation system is reducing over the years as more versions come onto the market and competition becomes tougher.
How to tell in your ventilation system is effective
Measuring ventilation performance in buildings relies on four different areas of inspection. This is rate of ventilation (ie is it sufficient), airflow direction, pattern (is it getting to every room in the building) and how well – or not – it is removing pollutants from each location.
This can be measured by an engineer using tracer and gas techniques looking at the average time it takes air to arrive in a room and how long it stays there. He or she can use injected tracer gas in a room to measure how long it disperses or the engineer can measure air velocity via ventilation openings and air ducts.
Want to learn more about the types of ventilation systems we offer? Get in touch today
To find out the types of ventilation systems that will work best for your domestic or commercial needs call the team here at Batchelor today. We can provide an initial survey of your premises, as well as a consultation with yourselves. This involves assessing your property and environment, together with looking at various ventilation strategies, depending on their robustness, cost, size etc.
You can have complete confidence in the abilities of the team here at Batchelor. Our length of experience is practically unrivalled in these parts. That’s because we have been fitting ventilation systems in Cambridgeshire, Oxford, Bedford and nearby for more than two decades now.
As you would imagine, we are 100 per cent up-to-date on the latest ventilation systems versions on the market. We have also worked with – and are familiar with – many of the top ventilation brands today.
In addition to installation, at Batchelor we also service, maintain and repair all types of ventilation systems – regardless of who the type of system, who fitted it, and when. You can call us for a chat about your ventilation needs anytime on 01234 712 901 write to us via our website www.batchelor.co.uk