Envirofan intuitive design, achieves effective sub-floor and underfloor ventiIation, without the use of flexible ducting. How so?
Before we answer this question let us look at the sub-floor area itself. We can liken it to a blank canvas board as used by an artist, the more brush strokes, the more detailed and busy the canvas becomes.
When it comes to sub-floor and underfloor ventilation, the more materials that are installed in the sub-floor area the more inhibitive air flow becomes, as the air has to travel around obstacles
Let us look at the worse case scenario, that of central ducted heating. Ducting in these systems is quite large from 150mm to 300mm. Once these ducts are installed, this could lead to sub floor and underfloor ventilation problems, as the air flow can be inhibited.
If the house is of solid brick construction, another airflow obstacle exists. The obstacle of sub-walls. Ventilation companies are called in to rectify this problem by installing more flexible ducting and, in some cases, penetrate through these sub-walls to accommodate the ductwork. This is ‘usually’ at a diameter of 150mm or 6 inches, which means the penetration has to be larger to accommodate the duct itself. If they do not make these penetrations, they usually run the ductwork through an established opening under doorways. Therefore, we are still left with the legacy of the ductwork under the home.
Another consideration with the use of ducting is that in-line fans incur a back pressure drop as the air is pulled through the duct. Therefore, the efficiency of the in-line systems is marginally lost.
Flexible duct has been used in the ventilation industry for years. However, if alternative ventilation practices deliver better results, shouldn’t they be considered?
At Envirofan, the approach is cutting edge. When we start with a blank canvas, we finish with one. This is to maximise effective cross-flow in sub floor and underfloor areas without obstructions.
Firstly, Envirofan can induce dry air from outside and force it into the underfloor area by the use of solar powered ventilation systems, which are installed on the exterior wall (see picture below) or by the utilisation of wire mesh vents. We then use brick size ventilation systems that are established in the sub walls to direct air flow from room to room at a rate of 2.5m3/per minute at 27db. Then extraction ventilators, which are mounted on the other side of the home, preferably on the east or south aspect, draw the damp air out. This is the objective of what is deemed cross-flow ventilation. In exceptional circumstances, where there is no accessible exit point for an extraction system, the use of flexible duct to the nearest external point is unavoidable and is used sparingly.
So the conclusion is : for optimum cross-flow ventilaton, keep your sub-floor clear and use flexible ducting sparingly
Get expert advice from Envirofan Ventilation Systems in Sydney, Brisbane, Melbourne, Adelaide and Perth.