With the majority of us spending more time indoors than ever before, both at work and at home, Indoor Air Quality (IAQ) is a hot topic of debate due to the negative effects this can have on our health. Clean air direct offer practical solutions to improve indoor air quality through quality products.

At CleanAir Direct, we're not just passionate about clean air – we're committed to sustainability and eco-friendliness. Our approach to improving indoor air quality is rooted in environmental responsibility, utilising energy-efficient technologies and eco-friendly materials whenever possible. With a focus on promoting sustainable practices and reducing your carbon footprint, we're dedicated to creating healthier homes while safeguarding the planet for future generations.

Please get in touch with us via our contact page or call us on 01494 790460 we will be more than happy to help or alternatively visit our Design Service page.

dMEV fans are constant flow units that are especially good at managing damp and mould-inflicted rooms. They are predominantly similar in size and design to standard 4”/100mm wall or ceiling mounted axial fans and are a great option to upgrade existing bathroom, utility room and kitchen extractor fans. Unlike MEV, these units are single room systems and generally take the place of a traditional intermittent extractor fan. dMEVs come with various functionality including humidistats, over-run timers and PIR (Passive Infra-Red) sensors and are generally axial fans with a few utilising centrifugal fan extraction.

MEV units allow for multiple room extraction from a single unit and are ideally situated in a central position in the home - usually in a loft space or service room - which allows ducting to be run from multiple areas of your house to it. Once the extracted air reaches the MEV unit, it is consolidated and vented out of the building in a single duct run to the outside world.

MEV units can be boosted from their continuous trickle extraction rate by two methods; most units will have either a wired or wireless boost switch option to allow for manual purging, others may also incorporate a built-in humidity sensor within the unit that tracks the moisture content in the air being extracted. Over-run timers and PIV (Passive Infra-Red) sensors and are generally axial fans with a few utilising centrifugal fan extraction.

Mechanical Ventilation Heat Recovery units are ventilation systems that not only extract air but also introduce fresh air into a building. By utilising heat sink exchangers, they glean the heat from the exiting air and use it to warm the incoming fresh air from outside, reducing heat loss and heating costs. As constant flow systems, MVHR units have the added benefit of helping to reduce internal pollutants whilst also controlling the replacement air flow, creating a gentle and balanced cyclical ventilation current throughout your home.

MVHR systems are whole house centralised systems similar to MEVs and are also available as single room units. Both whole house systems and single room units have boost options, raising the extract/intake speed by a combination of wired or wireless boost switching and/or humidistat sensor to remove humidity faster or allow manually controlled purging.

PIV systems are designed to force fresh, filtered air into a property causing a positive pressure imbalance in the building. This in turn forces the already present stale air and humidity out through the fabric of the building. In more modern builds where building design has improved to limit the loss of heat through the structure, pairing a PIV system with dMEV fan units in bathrooms, kitchens and utility rooms can create a controlled cyclical flow of air through your home, displacing the stale air and humidity and replacing it with fresh air from the PIV system.

Probably the best known and most prolific type of mechanical extraction, intermittent fans, as the name suggests, run only when activated, usually at a single speed. They can come in a wide range of sizes and styles with extraction rates suited to different applications. A range of functionality options are available such as over-run timers, humidistat sensors, built-in pull cords and PIR (passive Infra-Red) movement sensors.

Intermittent inline units are also available, again in various diameters starting at 4”/100mm. Inline units are designed to be housed within a run of ducting in loft spaces or service rooms out of sight and are therefore not designed to be aesthetically pleasing. But not being tied down to looks allows them to house much larger and therefore more powerful motors, giving inline units a far superior extraction rate.

A Centrifugal Fan is a type of fan that directs airflow at right angles to the intake of the fan and utilises centrifugal force to propel air outwards towards the outlet. In operation, the impeller of the fan rotates, drawing air into the fan near the shaft and propelling it perpendicularly from the shaft to the opening in the scroll-shaped fan casing.

This design allows a centrifugal fan to generate higher pressure for a given volume of air compared to axial fans. As a result, centrifugal fans are particularly suitable for situations where longer duct runs are required. They are commonly employed in both ceiling and wall-mounted fans as well as MEV and MVHR systems. This versatility makes centrifugal fans a preferred choice in applications where efficient air movement over extended distances is essential.

Axial Fans represent the predominant style of bathroom wall mounted fans, characterised by a specific impeller or blade design facilitating the movement of air along the axis of rotation. This configuration is commonly employed in domestic wall fans due to its efficiency. Many axial fans are particularly well-suited for small duct runs, typically those under 5 metres. They come in various versions, incorporating features such as timers, humidistats, pull cords, or Passive Infrared (PIR) sensors. Operational modes can be synchronised with lighting systems.

These fans are available in different voltage and construction options, including standard 240v, or 240v IPX4 (or higher) rated units and Safety Extra Low Voltage (SELV)
12v, suitable for installation in Zones 1 and 2 of the bathroom. However, it's important to note that axial fans are not optimal for extended duct runs exceeding 5 metres. Longer ducts can compromise their air extraction capabilities due to increased air pressures and resistance in the duct, making them less effective in such scenarios.

An Inline Fan is strategically placed within ventilation ducting, not directly in the room. Unlike visible wall-mounted fans, inline fans remain discreet, situated between extraction zones and the outside. Their centrifugal design excels in extended duct runs, maintaining effective extraction. Commonly used in bathrooms or kitchens, inline fans enhance ventilation by efficiently handling extended ducting, offering flexibility in installation for diverse environments.

A Humidistat is a device that measures the relative humidity (RH) of the air. It is utilised in ventilation systems to control fans based on humidity conditions. The humidistat monitors humidity levels, activating the fan when the preset threshold is reached and deactivating it when humidity falls below the set level. Commonly integrated into extractor fans, especially in humid-prone areas like bathrooms and kitchens, humidistats help manage moisture, prevent issues like mould, and contribute to indoor air quality. They can be integrated into fan units or installed separately, depending on the ventilation system design.

Constant flow or continuous ventilation is a strategy where ventilation devices operate at a low "Trickle Rate" 24/7, providing consistent air quality. These systems can be boosted for higher extraction during specific activities. Related terms include dMEV (Decentralised Mechanical Extract Ventilation), MEV (Mechanical Extract Ventilation), Heat Recovery (HR), and MVHR (Mechanical Ventilation with Heat Recovery), which enhances energy efficiency by recovering and reusing extracted air heat.

When picking a ventilation system, you may notice that the listing includes a Decibel (dB) rating. dB ratings for fans represent an average reading from a 3m distance without ducting, taken in a sound-controlled room to give as accurate a reading as possible. This offers a comparative measurement between systems but not an accurate reflection of installed noise levels. Once installed, there are many variables that can affect the perceived noise of a running fan such as the length and type of ducting used; the shape, surface type and size of the room; the type of grilles used; the position of the fan unit (especially with loft mounted units such as inline fans) - making it very difficult to predict exactly how loud the system will be perceived once installed.

Noise Control involves applying techniques and measures to minimise or manage the noise generated by ventilation equipment, aiming to create quieter indoor environments. This is crucial in residential, commercial, and industrial settings to enhance comfort, reduce disturbances, and comply with noise regulations. Key techniques for noise control in ventilation systems include selecting suitable equipment, employing vibration isolation methods, utilising correct connectors, ensuring proper equipment maintenance, optimising airflow management, and strategically planning equipment placement. A comprehensive approach to noise control helps create more pleasant indoor spaces for building occupants.

The answer to this is not as straightforward as you might think and depends on several variables. To begin with, different rooms require different ventilation extraction rates to meet building regs, and to complicate things further, these rates differ depending on the fan technology being used.

For whole house ventilation, part F1(1.24) of the building regulations state “the minimum rate for the supply of air to the habitable rooms…should meet the following conditions: a) a minimum rate of 0.3 litres per second per metres squared of the internal floor area” of the building… and “b) a minimum rate determined by the number of bedrooms” - whichever is the greater. Purge ventilation requires a minimum of four complete air changes an hour and with all these regulations, types of external openings (doors, windows, etc.) also need to meet specific sizes and opening abilities to be in line with the regulations. There are also regulations that determine internal door fittings to ensure that they provide a minimum free area to allow for air to pass when the door is shut, equivalent to 10mm above the finished floor in a 760mm wide door.

There are three types of backdraught protection; integrated protection in the fan, inline shutters mounted within the ducting run and external grilles with backdraught protection.

Intermittent fans excluding inline fans often come with an integrated shutter - these can be solid plastic spring-loaded shutters, low resistance membrane shutters orthermo-electric shutters. All three are as effective as each other at minimising drafts, with the best option being the low-resistance membranes that are easily blown open when the fan is in operation and fall back to seal the ducting when the fan is not in use, causing the least amount of back-pressure on the fan unit itself.

Inline fans have no built-in protection from backdraughts and are powerful enough to utilise an inline backdraught shutter. These are solid plastic shutters that are balanced to fall closed when the fan is not in use and pivoted to open when the fan blows through. These shutters are ideally placed close to the fan’s extraction side to make the most of the full airflow and minimise back pressure issues further down the duct run. Inline backdraught shutters are not recommended for use with standard axial through-the-wall or ceiling mounted fans and are not needed in constant flow systems.

Constant flow systems such as dMEV, MEV and MVHRs do not require a built-in or inline backdraught shutter as they are always venting outwards. Although this stops draughts from returning through the duct, external wind resistance can cause additional pressure on the fan unit. Installing an external grille that helps to minimise backdraughts can help to maintain the outward airflow and relieve any fan from the additional pressure caused by wind and backdraughts.

It is important to understand that no single backdraught system mentioned here is 100% effective, but a combination of these will give the best protection. For all fan systems, using an external grille that helps minimising backdraughts will help to maximise protection, ideally using a grille that causes the least amount of resistance, allowing for free air movement rather than external grilles with flaps that need to be pushed open by the outgoing air to allow it to escape.

The concept of Bathroom Zones is integral to the categorisation of spaces within bathrooms and wet rooms, helping installers in selecting appropriate products that adhere to safety regulations based on the likelihood of water exposure. In bathrooms and wet rooms, these zones help determine the suitability of installations for different areas. Bathrooms typically comprise three zones while wet rooms have two zones.

The assignment of zone numbers corresponds to the perceived risk of water exposure, with higher zone numbers indicating lower risk. For instance, Zone 0 represents a high-risk area, whereas Zone 2 is considered a relatively low-risk area. Each zone is defined by a specific three-dimensional volume, and any object or component within this designated "box" is considered within the corresponding zone. This zoning system ensures compliance with safety standards and guides installers in making informed decisions based on the potential for water exposure in different areas of the bathroom or wet room.

Zone 0 pertains to the inside of the bath or shower tray which may create a submerged area. Electrical items used in this space will require a minimum IPX7 rating. This applies to both bathrooms and wet rooms.

Zone 1 extends directly above Zone 0, encompassing the full bath or shower tray width. For free-standing bathtubs, the area beneath is also Zone 1. In wet rooms, Zone 1 continues around the drain away/plug hole at a 1.2m radius.

Zone 2 extends horizontally 0.6m beyond Zone 1, up to 2.25m vertically.

Electrical items in both zones 1 or 2 need at least an IPX4 or higher rating if mains voltage and wired to a 30ma RCD or RCBO protected circuit, or a low voltage model with a transformer located outside Zone 2 restricting the voltage to the
electrical item (usually restricting to 12v).

The Outside Zone encompasses the space beyond Zones 1 and 2, including above the 2.25m height. Lighting or extractor fans can be installed here without an IP rating. Ceiling pull switches for showers should be above the 2.25m threshold in the Outside Zone, with only the operating chord allowed in Zone 2 and not in Zone 1.

Part F of the UK Building Regulations focuses on ventilation requirements in buildings, addressing both dwellings (Part F1) and non-dwellings (Part F2). These regulations aim to ensure health, safety, welfare, and energy efficiency. Part F1 outlines standards for residential ventilation, emphasising indoor air quality and moisture prevention. Part F2 extends these standards to non residential buildings, covering areas like extraction rates, ventilation strategies, and energy efficiency. Regular updates and amendments occur, so consulting the official government website or local building authorities is crucial for compliance with the latest regulations.

A Condensation Trap is a device installed within a vertical duct run to facilitate the collection and removal of condensation from a venting system. This component is particularly prevalent in vertical venting configurations, especially those extending through roofs. Its primary function is to address the issue of condensation buildup within the ducting and to stop water running back into ventilation systems and rooms.

In vertical duct runs, as warm, moist air is expelled through the venting system, it encounters cooler temperatures at higher elevations, potentially leading to the condensation of water vapour. The condensation trap serves as a barrier to collect and channel this condensed water away from the venting system, preventing it from causing issues such as water damage or compromising the efficiency of the ventilation system. This addition is crucial for maintaining the integrity and optimal performance of vertical ducting, especially when positioned above the fan unit. Some systems have built in condensation traps where others will need a duct-mounted trap installed but both will need planning to decide where the collected water is plumbed away from the system. This can be into any wastewater plumbing or through an external wall or soffit as a drain-away, similar to condensate pipes on boilers etc.

Ventilation systems will help to combat damp issues in your building, however, with rising damp, ventilation will only help to manage the issue, not solve the problem. Rising damp is usually caused by damage to the damp course which allows moisture to spread up through the structure of the building. Repairing the damp course is the best solution for stopping this ingress of moisture. If you have a rising damp issue that cannot be stopped through maintenance of the damp course, then a combination of continuous mechanical ventilation and temperature control can help to control the spread of the moisture and slow damage to your building.

Solid ducting is always the best option for any installation. The smooth and regular internal surface causes the least amount of airflow friction which keeps airflow noise to a minimum and reduces back pressure in the duct allowing the fan to operate more efficiently.

However, some systems are designed to use different styles of ducting, for instance most MVHR and MEV systems can be installed using radial ducting which is a semi-solid duct that maintains as smooth an inner surface as possible but still allows for some flexibility for installation runs. Commonly, radial ducting will be supplied in smaller diameters so that it is easier to hide within the building structure. However, as flow rates rely on the ducting diameter being at least equal to that of the size of the fan, radial ducting is paired through a plenum terminal to allow two parallel duct runs to carry the required quantity of air.

Fully flexible ducting can be used and is often very helpful for difficult ducting routes through loft spaces. Flexible duct comes in both Aluminium and PVC; The PVC flexible duct is slightly elastic which can help in the initial install, but this means that the duct can stretch over time and sag which leads to condensate collections which can become problematic. Aluminium foil ducting not only retains its shape but is more widely recyclable and therefore a better choice should you need to use flexible ducting.

There are various styles of external grille available, the most common fall into four categories: standard fixed grilles, gravity grilles, no resistance grilles and roof kits. If you are installing ducting to exit through a roof or soffit, your choices are limited; for a roof extraction, either a roof kit or tile vent is needed with a weather cowl or mushroom cap to eliminate external elements entering the ducting. For soffit instals, a standard fixed grille is advised.

If you are installing a grille to an external vertical surface, then no resistance grilles are best. These grilles help to minimise backdraughts while causing no airflow impedance by keeping an open aperture for the out-going air. In contrast, gravity grilles incorporate hinged slats that fall closed when the fan is not in use and are blown open when the fan is in use. The downside to these grilles is that the fan has to push the slats open causing back pressure in the ducting which can put a fan motor under undue strain and shorten the life of the unit while also reducing the fan’s extraction rate. The slats can also clack in higher winds, causing an irritating noise.

The Extraction Rate refers to the amount of air extracted or removed from a space within a specified period. This metric is often expressed in two common units: cubic metres per hour (m³/hr) or litres per second (l/s). For example, an intermittent bathroom extractor fan might have an extraction rate of approximately 90m³/hr or 25l/s.

Converting between these units involves multiplying the l/s figure by 3.6 to get the m³/hr value. For instance, if an extractor fan has an extraction rate of 25l/s, the equivalent rate in m³/hr would be 25 x 3.6 = 90m³/hr. Similarly, the rule is reversible, so 90 ÷ 3.6 = 25l/s. Understanding the extraction rate is crucial in assessing the performance and efficiency of ventilation systems, ensuring that they meet the necessary requirements for air exchange in a given space.

Passive grilles or passive ventilation refers to non-mechanical vents that leverage natural forces for airflow without powered fans. These grilles or openings facilitate the exchange of air, utilising wind, buoyancy, and temperature differences. Trickle vents offer continuous low-level airflow, adjustable for control even when doors or windows are closed.

The downside to passive venting is the lack of control to heat loss and cold air and moisture entering a building. Regulated trickle venting via continuous mechanical ventilation controls the rate of outward airflow and stops unwanted inward drafts.

Many fan systems that use filtration are supplied with filters that can be either replaced or are washable and reusable, but not all. Depending on the type of filtration being used, some filters will have to be disposed of and replaced periodically. It is always worth checking with the manufacturer to confirm whether a specific filter can be reused or not.

Indoor Air Quality (IAQ) refers to the cleanliness and healthiness of the air inside a building. It involves factors like airborne pollutants (dust, pollen, mould spores, VOCs), temperature, and humidity. Maintaining IAQ is crucial for occupant well-being and comfort. Key aspects include proper ventilation to exchange indoor air, control moisture, and enhance oxygen supply. Ventilation systems, including fans and filters, play a vital role in improving IAQ and involve effective ventilation strategies for minimising pollutant sources. Regular monitoring is essential for a healthier indoor environment.

Bathroom electrical appliances, including extractor fans and lighting, receive an IP or Ingress Potential rating indicating their suitability for specific zones. The IP rating consists of two digits following 'IP,' where the first digit denotes protection from solid objects. However, our focus is on the second digit, representing protection from water and moisture. A higher second digit implies increased protection against water ingress. An IP rating of IPX4 or higher is safe for installation in zone 1 of a bathroom on mains voltage when installed on an RCD or RCBO protected circuit.

Kitchen fans are designed to remove air from the kitchen that contains particulate matter and gases associated with burning fuels to improve the quality of the indoor air. Cooker hoods are designed to extract from directly above a hob and pull the air through a filter to remove the particulate matter. These can then either extract externally or recycle the filtered air back into the kitchen. If the cooker hood extracts externally at a rate of 30l/s or higher, you do not need an additional extractor fan in the kitchen. However, if the extractor fan recycles the air back into the kitchen or if you do not have or do not want a cooker hood, then an additional kitchen fan is needed. You can either install an intermittent extractor fan that achieves a minimum of 60l/s or a continuous flow extraction unit.

Calculating the minimum trickle flow rate for a continuous flow kitchen fan is again not completely straight forward, but as a general rule of thumb, set your trickle speed for a minimum of 13l/s if in doubt - this will more than meet the building regs threshold.

If you have a longer duct or a larger than average kitchen, then it may be worth seeking advice on suitable extraction rates which can be calculated for you through a specification based on the room size and duct lengths involved.

Mechanical Ventilation involves the use of powered fans to actively circulate and control airflow within a space. This method provides precise control over ventilation rates, contributing to improved indoor air quality. Common in residential, commercial, and industrial settings, mechanical ventilation ensures consistent and controlled airflow, addressing spaces where natural ventilation may be insufficient. These systems are designed to meet specific ventilation rates, promoting energy efficiency through technologies like variable speed controls and heat recovery. Different types of mechanical ventilation systems are employed based on the specific requirements of the building or space.

dB ratings for fans represent an average reading from a 3m distance without ducting, offering a comparative measure but not an accurate reflection of installed noise levels. Once installed, there are many variables that can affect the perceived noise of a running fan: the length and type of ducting used; the shape, surface type andsize of the room; the type of grilles used; the position of the fan unit (especially with loft mounted units such as inline fans) - the list goes on! The two examples below illustrate how different installations impact perceived noise levels:

Inline Fans and Ducted Installations - In a typical inline fan installation, attaching ducting increases noise due to airflow resistance, friction, and surface reflection. You can help minimise noise by using solid ducting for smoother airflow and ensuring flexible ducting is installed taut if used to reduce peaks and troughs in the inner surface of the duct. Choosing suitable internal grilles with minimal airflow obstruction is crucial. Avoiding metal diffuser grilles is best as these can cause a higher level of noise when installed with more powerful inline units and can corrode when used in bathrooms due to the high concentration of moisture pulled passed them. Fan unit position and vibration reduction methods under the unit can further reduce perceived noise.

Through-The-Wall Installations - Axial fans have fewer variables affecting perceived noise. Ideal installations utilise solid ducting directly through the wall, connecting to an external grille. Free air replacement back into the room is essential to let the fan work without additional strain which will minimise motor noise and external vent choice (preferably without a fly screen) minimises resistance.

Choosing appropriate components and addressing variables in each installation type can help minimise perceived noise levels.

Every fan on our website will show a noise rating measured in decibels (dB). Decibels as a measurement of sound can be confusing, as the linear rise in decibels does not correlate to the logarithmic curve that tracks the perceived volume we hear as humans. Effectively, the best way to describe how we perceive sound is that the perceived volume we hear doubles every 10dB.

For the most part, when it comes to extractor fans, we are unlikely to look at anything above 50dB unless we are talking about commercial units - but this is where we hit a snag. The dB ratings on the fans are an average dB reading taken from a distance of 3m while the fan is not attached to any ducting and in an environment that gives a true dB level unaffected by variables such as natural amplification or additional noise pollution affecting the readings taken. This is great for giving a level that can be compared against other units including from varying manufacturers, but it means that this level is not a true representation of how the fan noise level will be perceived once installed in your home.

Mechanical extraction for odour control employs various methods and technologies to effectively eliminate or neutralise unpleasant odours from the air. This process involves using fans or other mechanical systems to physically remove air from a space. There are systems available that can sense a change in the air quality - essentially smelling the air - and will trigger to vent the area. Most standard ventilation systems for the home will help eradicate bad smells simply by removing the particles in the stale air to replace with fresh air. Of course, removing the source of the smell from the home is also recommended!

If you are installing either a ceiling-mounted fan or a loft mounted system such as an inline fan which incorporates a ducting run through loft space, finding the best place to exit the building is important. Ideally, you want to take the shortest route to the outside, however the most direct route might not be the best option. There are three external fitting options for extraction points: through an external wall, through a soffit or through the roof. If possible, we would recommend trying to avoid the latter option of venting through the roof. Installing roof vents can be problematic for several reasons: firstly, you are creating a hole in your roof - no matter how well the installation is done, at some point down the road there is the potential for leaks through the roof around the venting point. Secondly, you will need a professional roofer to install the vent which is another cost to add to your installation. And thirdly, and in our opinion the most important reason to avoid roof venting, due to the ducting running higher than the fan unit, you will need to incorporate a condensation trap into the duct run to stop condensation from running back down the duct and into the fan unit. Condensation traps need to be plumbed somewhere to allow the condensate to run off, this either means finding a wastewater pipe to attach to or having the condensate pipe exit the building through a gable end wall or soffit, similar to a boiler condensate pipe, to allow the water to drain away naturally.

It is always a far more straightforward option to mount your external grille through a soffit (if accessible) or a gable end wall. This will allow you to keep the exit point lower than the fan unit and allow for the ducting to run at a slightly downward angle towards the external grille, meaning that any condensation forming in the duct will naturally run towards the exit point and not back towards the fan unit. This means no condensation trap is needed. You can always raise an inline fan to create a steeper angle for the runoff and if you are installing a ceiling mounted unit, you can raise the ducting slightly at the ceiling mounting point to create a downward angle to run away from the fan position.

If you are installing a heat recovery system with separate intake and exhaust points, it is important to not install these external vents close to each other. You do not want your intake to be pulling back in the stale air you have just vented outside!

Radon is a naturally occurring radioactive gas that in its natural state is colourless, odourless, and tasteless. This makes it imperceptible to human senses, and individuals may not be aware of its presence without testing. Radon gas increases the risk of lung cancer if exposed to high levels over prolonged periods and smokers or individuals with pre existing respiratory illnesses are at a higher level of risk from exposure. It is formed by the decay of uranium, a radioactive element found in varying amounts in soil and rock. Radon can migrate from the ground into buildings, where it may accumulate to potentially harmful levels. It can affect buildings of all types but is often significantly more common in buildings with basements.

Radon levels can vary geographically, and certain areas may be more prone to elevated radon concentrations due to the local geology. It is essential for property owners, especially in radon-prone regions, to test for radon regularly.

Radon testing kits are available for use in homes and other structures. If elevated levels are detected, mitigation techniques, such as increased ventilation and the installation of radon mitigation systems, can be implemented. Because radon is a potential health risk, individuals are encouraged to test their homes for radon regularly, especially in areas where elevated radon levels are more common. It is important to use a kit that will be tested in a validated laboratory.

If you want to check whether you are in a geographical area prone to Radon, or if you need to order an accredited domestic test kit, you can order a report based on your address at the UK Health Security Agency website in the link below.

https://www.ukradon.org/

If you have completed a test and the results show an elevated Radon level, please feel free to contact us and we will be happy to look at suitable systems to combat this issue for you.

Total Equivalent Length (TEL) in ventilation systems quantifies the cumulative resistance to airflow caused by ducts, fittings, and components. TEL plays a key role in achieving balanced, efficient, and well-performing ventilation systems. All fan units will have a maximum ducting distance that the unit can cope with, based on the cumulative resistance caused by the distance travelled, and these are all based on a straight line of duct. For example, if a fan states that it can duct up to 5m, this is assuming the 5m run is in a straight line with no additional bends in the ducting, changing the direction of the route taken. The general rule of thumb is that a 90-degree bend adds the same amount of resistance as a straight metre, therefore meaning that if you need to make two 90-degree bends in your duct run, you will need to add two metres to the overall length of ducting used. Again, a fan that states it can duct up to 5m will only cope with 3m of straight ducting run with two 90-degree bends. Trying to install a fan with a TEL of ducting that is longer than the stated maximum length that the fan is capable of venting through will put the fan motor under undue strain which will not only negatively affect the extraction rate but will also shorten the life of the motor unit. It is therefore important to calculate these distances correctly to maintain the efficiency of your extraction.

Volatile Organic Compounds (VOCs) are generally caused by cleaning and personal care products, building materials and other common household products such as cleaning products, air fresheners, deodorants, and other aerosol-based products and even carpets and furniture. You can try to avoid bringing sources of VOCs into your home, but this is not an easy task without completely changing your way of life! The simpler option is to integrate a suitable whole-house ventilation system to effectively extract VOCs from your home.

Firstly, keep your windows closed, this may seem counterintuitive when you’re standing in a room full of steam. However, an open window in midwinter is one of the main contributors to condensation, mould, and damp problems in UK homes. This is because when the cold air from outside mixes with the warm humid air from the shower it forces the moisture to condense faster forming into larger droplets of water. Keeping the windows closed helps to keep the room warmer and reduces the speed at which water molecules in the air condense making them easier to extract. Additionally, the cold air cools the tiles and other surfaces in the bathroom which adds to the speed at which the moisture condenses.

Wipe down excess water after showering. All that water collected on the wall tiles, shower screens, mirrors, windows and shower trays has to go somewhere. Yes, some of it will go down the plug hole, but most of it will evaporate and add to humidity issues or soak into surfaces causing further damp and structural issues.

So, invest a few pounds in a shower squeegee and spend a couple of minutes getting rid of that excess water. This not only effectively removes all water droplets it will leave your glass and tiles looking squeaky clean!

If your system has developed a fault, we kindly ask that you first contact the manufacturer’s technical department directly, who will troubleshoot the issue with you.

If the manufacturer confirms that you do indeed have a faulty unit, please contact us and we will be happy to arrange the replacement of the item or refund if applicable under the manufacturer's warranty.

There are various reasons why a fan is underperforming and most of these are easily rectified. Here are a few tips to try which should help to improve your fan performance. The biggest culprit is air flow resistance, either before the fan or after the fan. As air is forced through ducting, there is a level of resistance from the friction caused by the inner surface of the duct. If flexible ducting has been used, make sure it has been installed as taut as possible to minimise internal peaks and troughs which appear when the ducting is left slack. Remove any excess ducting and try to create the shortest and most direct run as straight as possible. This applies also to ducting running to the unit as well if you have an inline style fan. Make sure that the total equivalent length (TEL) of the ducting distance does not exceed the maximum range that the fan system can cope with as this will also slow the fan extraction rate.

Any fan will also struggle to maintain its expected extraction rate if there is not an ample supply of free air allowed to replace the that which is being removed by a fan. For example, if you have a bathroom with a well fitted door when closed, it is possible the amount of air that can be pulled passed the door frame is not equal to the air quantity that the fan is attempting to extract. This places the fan motor under additional strain and will slow the rate of extraction to the point that the fan is happy to run at to balance the rate of air entering the room to replace the air leaving the room. A simple test to see if this is affecting your extraction is to leave the door ajar to see if this improves the extraction rate. More modern builds can commonly have this issue, however, current building regs state that internal doors should have a 10mm undercut above the finished floor in a 760mm wide door to allow for free air movement. If you have a particularly powerful fan, or a well fitted door that you do not want to re-hang, you can also combat this by installing a passive internal door vent through the bottom of the door - keeping your privacy but allowing for a greater flow of air to be pulled into the bathroom at ease. These are a great option to pair with constant running fans.

In summer months, opening a window will also help but you want to avoid any passive external openings to prevent both heat loss out and the drawing in of cold air which will exacerbate moisture, damp, and mould issues.

Please contact us through our Returns page which also holds information on how to return items to us.

Please email us using our Contact Us form to request a copy of your invoice with your full name and the order number for the invoice you need.

Our aim is that all stock items ordered before 4pm Monday to Friday are dispatched on the same day, for delivery the next working day. This does exclude some of the more remote Welsh, Northern Ireland, and Scottish Highland and UK offshore postcodes, which are usually delivered within 2-3 working days. If you require a product urgently we suggest that you contact us first to ensure we have the appropriate stock levels.