A musty room, condensation is causing an issue – then this is for you
Constant running fans have been around for a number of years but are becoming more prevalent as changes to house building, regulation and the increase in home insulation have all conspired to reduce the amount of natural ventilation (air leakage) that occurs in our homes. This is of course intended but a side effect of wrapping our houses up so they stay warm is that they don’t ‘breathe’ like they used to.
In 2004, the number of air changes per hour you could expect to occur in a property was 16.9. Today, that figure is below 4 so the level of natural ventilation has decreased dramatically. Whilst the majority of fans sold are for the refurbishment market, and a lot of houses are still ‘leaky’, the point is clear that as houses are wrapped up tighter, then there will also be a corresponding decrease in natural ventilation. Ultimately, this leads to a situation whereby moist air is trapped in buildings which becomes stale and as a consequence there is a rise in mould and condensation issues. The potential for problems to occur are made clearer when it is estimated that just taking a bath or shower can release as much as 2 pints of moisture into a room.
Because of this reduction in uncontrolled natural air leakage, the use of controlled continuous ventilation has increased. As opposed to traditional intermittent ventilation which is designed to operate on a high speed only when the room is in use, continuous running fans, as the name suggest, run for 24 hours a day 365 days a year. The principle used is that for the majority time when the room is unoccupied, the fan will run on a low background speed and boost to a higher speed when the room is in use - as with intermittent ventilation. The point of this is that the low level continuous running helps replace some the traditional background ventilation that no longer occurs due to ‘tighter’ house builds and increased insulation keeping the room fresh.
There are two issues to consider with this approach – one is that of noise and the other is that of energy use. Generally, the sound of the fan is not an issue as they are designed to run on a very low speed for the majority of the time and so the sound of the fan is also very low. To explain this, when running on low speed (5 litres per second in line with Building Regulations) they make just 10.1d(B)A. which is about the sound level you can hear when leaves rustle. For a further explanation of d(B)A and silence please click here for SILENT PAGE. As for energy use, our continuous running fans use modern DC motors which not only help limit the sound of the motor running but also help with energy efficiency. As an example, our bestselling continuous running product – CV2GIP when used 24hours /day365 days/year, will only cost about £1.50 per year (Yes, that’s £0.03p per week) to run.
So if you have recently refurbished or insulated your home, have a bathroom, shower or en-suite with no windows, a problem room which is perennially musty and suffers from condensation or just gets a lot of use, then continuous ventilation is something which you should consider.