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A breath of fresh air
Intermittent Extract Ventilation
Classic or standard intermittent extractor fans are still some of the most popular bathroom and kitchen fans - they should really be in the running for a lifetime achievement award!
Traditional in design yet modern in style, this type of kitchen and bathroom fan ticks all the boxes when it comes to refurbishment, therefore, it’s no wonder that time and time again they are specified by key social sector clients.
Today a range of motor types, performances and controls are available in intermittent fan models including Axial, Centrifugal and Mixed Flow and then humidity, timer, delay timer, pull cord and more... Performance is key with intermittent ventilation because the fan is only on for a short amount of time.
Consider application each and every time as where and how you install a fan impacts on it's performance e.g. a fan which goes through the wall will performance differently to one that is installed in a ceiling with 3m of flexible ducting.
Building Regulation Requirements ADF: 2010
Providing ON-OFF ventilation, each fan is sized based on room type;
We have seen a massive adoption of Continuous Ventilation into existing homes - especially with social landlords.
How does it work?
Continuously running extractor fans are installed in the wet rooms of the property, e.g. bathroom and kitchen
In accordance with Building Regulations, the fans are set to continuously trickle with a boost option that can either be wired into a light switch or can automatically boost e.g. in response to humidity levels within a property
The fans run 24 hours per day (usually 22 hours on trickle and 2 hours on boost) but this is directly related to occupancy in homes.
Why have we seen such huge adoption in social housing specification?
Continuous ventilation has many benefits and offers solution to many social housing issues - especially mould and condensation mould and condensation.
Continuous Ventilation offers an all round low energy, low noise solution for tenants - and it protects the building effectively. One of the major benefits is that it can be installed in the same place that a traditional intermittent (ON/OFF) fan would have been, meaning little or no remedial work for the contractor or landlord.
Continuous Ventilation provides excellent air change to a property all year round at extremely low running costs - in fact, the equivalent of less than a penny a day to run for the entire year!
Choose continuous ventilation if you have consistent mould and condensation issues...
The graph above shows the difference between intermittent and continuous ventilation and the filled colour sections indicate the amount of ventilation provided to the property within a 24 hour period.
Continuous ventilation offers a consistent low level extraction of moisture from the property with an intermittent boost and, therefore, a much higher rate of air change within the property throughout the days, week, months and years. If there are issues with mould and condensation, this methodology will work to eliminate these issues effectively.
Don't worry though - With low energy designs and motors, continuous ventilation offers an effective ventilation strategy that costs occupants less than a penny a day to run for the entire year!
Specify one single product for all your ventilation needs - one man, one van, one fan! Efficiency is a cornerstone of most organisations' policies and objectives and it is this policy that was part of the evolution of the first truly multi-functional fan in the UK domestic ventilation market.
Multi-function is a new type of single point fan - a fan which serves many installation applications and requirements and is especially beneficial to landlords managing, updating and providing responsive maintenance to large housing stocks because it is a single specification solution.
The straight line approach
What do we mean?
The straight line approach brings efficiency to the top of the agenda.
Imagine a large scale planned maintenance program. A multi-functional fan like Omnique can be installed in every single bathroom and kitchen within that programme - in apartments or houses and working continuously or wired into the light switch.
Imagine ten calls are made about broken fans. A multi-functional fan like Omnique can replace any existing fan. Therefore, there is no need to drive to the property, survey the fan, drive to a depot or wholesalers to source the fan, drive back to property and finally fit the fan. You simply drive from property to property using Omnique as the single product specification - the straight line approach!
Intermittent and continuous ventilation as best practice to Building Regulations
Whether in intermittent or continuous mode, the Multi-function fan provides airflow rates as set out in ADF:2010.
Noise is a nuisance and is the last thing that you want in the comfort of your own home. In new build particularly it has become an increasing issue as a result of Brownfield re-development and density planning guidance notes. What this has meant is that homes have more chance of being sited close to busy roads, railways and airports, meaning more noise which has an impact on the domestic environment. Noise sources can be both internal and external; from the external environment and location, internally between rooms/apartments and even from products, all of which must now be considered at the design stage.
What is acceptable noise?
The decibel scale runs from the faintest sound the human ear can detect at 0dB to well over 180dB which is similar to the noise a rocket creates during launch.
The Building Regulations support the control of noise - from external sources entering the building and from the ventilation system itself within the building. It is moving up the agenda at every single revision and planning restrictions continue to be placed on sites where external noise transfer will be a problem.
For ventilation systems, ADF:2010 suggests the following sound power levels for continuously running systems:
An upper limit of 30dB(A) weighted sound power level.
An upper limit of 35dB(A) weighted sound power level.
When a site requires acoustic protection it is usually considered at the design stage. This sometimes means that certain building elements can no longer be used as a source of ventilation, e.g. windows. In this instance it may be essential to provide acoustic ventilation solutions that provide the necessary airflow but reduce noise transfer. The nature of acoustic products means that they are usually much larger than their standard counterparts, meaning that a like-for-like installation cannot always be easily achieved. When acoustic ventilation is required this should also be considered at the design stage, as the noise factor may actually pre-determine the method of ventilation that will be used within the dwelling.
A more effective approach to acoustic design - MVHR
With most ventilation systems, a number of penetrations in the external facade or windows are required to allow air in and out of the dwelling. It is these openings that allow noise transfer from outside and acoustic versions are often the first point of call as they continue to ventilate, but also attenuate the external noise transfer.
An alternative solution would be to review the entire ventilation strategy for the building. An optimal solution for reduction of noise transfer is Mechanical Ventilation with Heat Recovery which works as a whole house system, both extracting and supplying air which negates the need for window ventilators. The design of an MVHR system requires only two penetrations in the façade of the building, therefore providing a more effective design led solution for any site with noise issues.
When dealing with acoustic issues on site, it is not as simple as replacing a standard product with an acoustic version. Other options such as heat recovery ventilation can provide effective whole house performance to Building Regulations as well as comply with any ventilation noise planning restrictions that have been put in place.
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