Sub-floor Ventilation

Dampness in the sub-floor area is common in many ages and types of homes, but as Sydney sub-floor ventilation experts, Buildwyse Constructions can install an innovative long-term solution.

What causes sub-floor dampness?

If one of more of the rooms in your house seems a bit musty and mouldy despite being well ventilated, it might be due to moisture underneath the floor rather than above it.

Moisture in the sub-floor – the cavity underneath the lowest floors in your house – has a number of possible causes. Sometimes it’s the location: where the house is built over moist clay subsoils, or in a poor drainage area such as a slight depression in the land, or where the sub-floor cavity is partly submerged into the ground. This may be exacerbated by the micro climate of the property, with lack of sun due to shade or shadow allowing moisture to linger. Other factors will be due to the building itself, like inferior construction or outdated design.

Older buildings often suffer a lack of ventilation in the subfloor, with decaying floor frames causing mould problems in the rooms above. To the expert eye, an immediate indicator of moist sub-floor dampness in older homes is rusty nails in wooden floors. The hole made by the nail lets moisture escape and the nail oxidises, also staining the wood around it.

How is sub-floor ventilation improved?

Homes with mild sub-floor moisture often simply require wall vents, or more of them, to allow air to circulate in the sub-floor cavity and dry out the damp.

However the nature of some homes prevents wall vents from being effective. For example, most of the wall length of a terrace house is the wall of the sub-floor under the home next to it. The only real external walls are the narrow front and back, where wall vents cannot provide the amount of airflow required for the length of the building.

For severe cases a mechanical sub-floor ventilation system is a torpedo vent with an extractor fan to pull moisture out from under the floor. The low-voltage power can be supplied by a solar panel, which we can install as part of the job.

Don’t put up with mouldy or musty rooms when the solution can be very effective. We have a sub-floor ventilation expert and solar power specialist. Get in touch for an obligation-free onsite consultation.

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