Under House Ventilation Sydney from Envirofan

Cul-de-sac ventilation refers to an under house ventilation pocket of sub floor space which does not have any exterior vents on the external wall due to various factors:

Factors:

• Where concrete slabs surround the suspended floor area on 2 or 3 sides.
• Where the ground level outside the building is at the same height as the internal floor level.

To remedy this condition can be done by lowering the external ground level by retaining walls and installing adequate ventilation. There is an exception to the rule whereby flexible ducting would have to be utilised to extract the damp air from these 'dead spots' or 'dead area'. Dead meaning that air flow is non-existent. The Envirofan quad fan system as shown in the video is utilised for various reasons:

• Quiet operation (27dba) which does not translate to any undue noise in the dwelling or building unlike 240v systems. (27dba is approximately a third of the noise of a modern domestic refrigerator).
• That the solution is placed at the source of the problem.
• Being 12v this caters for significant power consumption reductions than 240v systems.
• Utilising two (2750litres/min) or four (5,500litres/min) individuals fans means that the sub floor ventilation properties will continue at a slight loss if one impeller ceases to operate, whereas with a one fan ventilation system sub floor ventilation, properties would be totally lost when the impeller ceases.

Application:

At the problem area where the musty smell is most pronounced inside the dwelling.

Where a brick size dual fan system cannot be installed on an exterior wall.

Where discolouration (darkened appearance or fungi) on the soil is apparent as compared to other soil appearance in the sub-floor area.

To ventilate at the centre of the dwelling (incidental to brick veneer construction) Located in the middle sub-floor area of the dwelling whereby fresh air can be drawn in through the existing exterior passive vents then extracted through the sub-floor ventilation system through ducting to the double brick size Envirofan passive vent mounted on the exterior wall.

Designed to ventilate 'cul-de-sac' areas provided that there is sufficient sub-floor access. Envirofan Sub-floor Ventilation Sydney.