Ventilation systems have never been more important as we battle against an ever-evolving pandemic, and crucially, they must be installed correctly to deliver good indoor air quality for years to come. David Millward, Group Product Manager at Elta Group, explains the practical considerations needed for contractors in charge of installing them.
Good indoor air quality (IAQ)
With a pandemic that has been raging for going on two years, there has never been a time where good indoor air quality (IAQ) has been more in focus. Particularly in public spaces such as offices, shopping centers, schools, and a whole range of other buildings, improving IAQ is now a must, and not a ‘nice-to-have’.
There are key installation factors that can make a substantial impact on system performance
To deliver this, ventilation contractors will have a critical role to play. There must first be a good understanding of what good IAQ is. As well as that, there are key installation factors that can make a substantial impact on system performance.
What is a ‘breath of fresh air’?
Much focus surrounding IAQ has been on the introduction of ‘fresh air’. Here though is where there must be a better definition and awareness of what ‘fresh air’ is. Everyone involved in the ventilation supply chain needs to know this, from manufacturers and government to contractors and even the general public.
Currently, there is a common misinterpretation that ‘fresh air’ is simply air that is brought in from outside. However, in certain environments like urbanized areas, quite often this air that is brought into the building can contain high levels of pollutants.
To help clarify what good IAQ is, there have been changes to Parts L and F of the Building Regulations. These changes seek to provide a more concrete definition and promote more monitoring of air quality in buildings. It is highly recommended that contractors stay abreast of evolving legislation as this is likely to impact the systems that they install in the future.
Don’t overlook the noise
Isolating the fan from the structure and the duct can greatly minimize structure-borne noise
Delivering a comfortable internal environment goes beyond just air quality, and here contractors can add a lot of value to their work. For example, one factor of ventilation installation that is regularly forgotten about is noise. By the time it is noticed however, it is typically too late to rectify without incurring significant cost and disruption.
Noisy ventilation can be easily remedied though. For duct-borne noise, this can be reduced by using attenuators (which is also useful for air-borne sound) or using lined fans and duct lining.
Meanwhile, isolating the fan from the structure and the duct can greatly minimize structure-borne noise. In quieter locations, such as restaurants or libraries, lowering a fan’s noise output can be particularly important to the overall setting.
Vibration control
Vibration control is equally important, as this contributes to noise and impacts user comfort. Inevitably, fans will vibrate, and this can reverberate through the structure it is mounted to. Vibration isolators are an easy solution to this issue and should be selected to offer the minimum deflection required.
When selecting vibration isolators, care should be taken to ensure they are suitable for the fan and the environment where the fan is operating. Flexible duct connectors are also available to aid in the reduction of both noise and vibration. These are just a few of the many options available to contractors, with a more comprehensive list detailed in Elta Fans’ Give a Fan a Chance guide.
Talking of flexible ducts, if improperly designed, these can severely impact the ventilation system’s performance.
Ducting
Talking of flexible ducts, if improperly designed, these can severely impact the ventilation system’s performance. The reason is flexible ducting can introduce resistance, which means a much higher pressure and power output is needed to reach the desired performance.
A common scenario is when a lot of unnecessary flexible ducting is installed in a roof space. This tends to happen when installers purchase 10m of the product when realistically only 3.5m is required. However, instead of cutting the ducting to size, the entire length of the product is installed in a snake shape that places additional pressure on the fan.
Ultimately when this happens, airflow is reduced, and there’s an increased risk of poor ventilation. Consequently, contaminants, particles, viruses, and airborne diseases linger in the air. Ideally, rigid ducting should be used wherever possible, with flexible ducting only used for final connections. It is also best practice to ensure all ductwork is taut.
Partnering up
Now more than ever, knowledge of how to deliver good IAQ is a vital skill. Ventilation contractors are at the forefront of constructing healthy buildings and combatting COVID-19. That said when it comes to keeping up with the latest developments and the most effective ways to install products, having a good partner can be the differentiator.
