Modern properties are designed and constructed to be as airtight as possible. While this reduces heat loss and maximises energy efficiency, it comes at a cost - A lack of natural ventilation means that moisture, stale air and pollutants can be trapped inside.
Over time this can lead to both mould growth and poor indoor air quality.
Decentralised Mechanical Extract Ventilation (DMEV) extractor fans are designed to tackle this issue, offering continuous low-level ventilation in cost-effective packages. This post will breakdown the practical advantages of DMEV extractor fans, and help you decide if they’re suitable for your property.
First off, what is DMEV?
Unlike standard extractor fan systems, which rely on a central unit and ducting to expel stale air and circulate in new air, DMEV systems operate as continuously-running self-contained units.
This both ensures a constant flow of fresh air and eliminates the need for excessive ductwork, which is otherwise needed to connect multiple rooms to a single fan unit.
Not only can this save a great deal of space, it opens the door to tailored ventilation. Standard mechanical extract ventilation (MEV) systems need to be set to address the most humid areas of a property, like bathrooms or showers, but DMEVs instead allow each room to receive the exact amount of ventilation it needs. This alone can make a property more energy efficient and comfortable.
You can find out more with our guide to how DMEVs work.
Continuous Ventilation for Consistent Air Quality
The link between indoor air quality (IAQ) and health is well established - Poor IAQ has been linked to a range of conditions, from minor annoyances like throat irritation and headaches to more severe issues like asthma and respiratory infections.
Excessive moisture, on the other hand, can lead to problems ranging from condensation to black mould growth to even, in extreme cases, structural damage.
Although standard extractor fans and MEVs can improve indoor air quality, they can only do so much as they normally rely on manual activation or timers. This means that while ventilation is provided on-hand when required (For example when cooking or taking a shower), pollutants and humidity are allowed to accumulate when the MEV is not in use.
DMEVs provide a round-the-clock alternative by continuously circulating fresh air to prevent moisture, pollutants and odours from building up. This is especially helpful in damp areas like bathrooms and utility rooms where mould and mildew can grow. Many DMEV models go the extra mile with built-in humidity sensors, which detect changes in a room’s moisture level and increase the extraction rate to compensate.
Altogether, this contributes not just to a healthier indoor living environment but a more comfortable and odour-free one.
Energy Efficiency and Cost Savings
Despite their continuous operation, dMEV fans are extremely energy-efficient and inexpensive to run.
Unlike standard MEVs that require sudden bursts of power, DMEVs provide a constant level of ventilation with far less energy consumption. Most models use energy-efficient brushless DC motors and specially-designed fan blades to strike a balance between effective ventilation and low energy consumption.
These both contribute to lower energy consumption, reducing operational costs and making DMEVs a cost-effective solution for maintaining indoor air quality. Our bestselling Greenwood Unity CV2GIP, for example, runs on as little as 2.1W, which translates to an annual running cost of only £3.65. A dishwasher, for comparison, has an annual running cost of £68 per year.
Near-Silent Operation
The more powerful an extractor fan the noisier it will be - But this doesn't mean you need to sacrifice peace and quiet for indoor air quality.
DMEV units are designed to operate at very low decibel levels, normally below 20db (Comparable to a whisper or the rustling of leaves). This is achieved with a combination of careful fan blade design, advanced motor technology and vibration-dampening materials in the construction.
The result is continuous round-the-clock operation without any disturbance to household activities or sleep, wherever they happen to be installed.
Simplified Maintenance
DMEVs are not only efficient and quiet, but remarkably low-maintenance.
Their simple design and robust construction minimises the need for frequent upkeep and cleaning. If cleaning a DMEV is necessary, it's rare that you will need to dissemble and clean the interior components - Most of the time they demand little more than a wipe with a soft bursh or damp cloth. In comparison, cleaning a typical MEV requires access to the attic or cavity where they are installed and the labour-intensive dusting of the entire ductwork.
Some DMEV models take this a step further with filterless designs, eliminating the hassle of regular filter replacements.
This low-maintenance approach is a boon for homeowners, landlords, and property managers, who can enjoy the benefits of DMEVs without the burden of frequent maintenance tasks.
Ease of Installation
Most extractor require at least some measure of ducting to vent interior air outside. Unless a new extractor fan is being retrofitted, this means the hands-on and potentially expensive process of planning, placing and securing ducting.
As they are designed as self-contained units focused on a single room, DMEVs don’t demand extensive ducting for effective ventilation. Their relatively small footprint makes them especially suitable for rooms where there isn’t enough space in the cavity for ducting.
Similarly, many DMEV fans come with pre-assembled components including the ventilation unit itself, external filters and mounting brackets. Combined with their discreet and unobstructive design, this allows for easy installation near windows, doors or utility rooms, streamlining installation without disrupting the property's overall aesthetic.
Conclusion
The key benefit of DMEVs is their ability to provide clean, fresh air without sacrificing comfort or incurring excessive energy costs.
By providing continuous low-level extraction, DMEV fans work to effectively manage moisture, eliminate pollutants and reduce the risk of mould growth. Their energy-efficient design, near-silent operation and low maintenance requirements makes them a practical and cost-effective choice for homeowners, landlords and housing associations alike.
If you would like any further help, please feel free to contact our friendly team for some expert advice on 0203 994 5470, drop us an email at sales@electricpoint.com or use our Contact Form.