Subfloor Ventilation Inspections from Exopest Control

Good subfloor ventilation improves the health of the occupants by reducing airborne fungal spores.

Many Edwardian double brick homes have a musty smell, originating from poor under floor ventilation. This is often compounded by under floor ducting heating systems which further reduce natural air movement.

Ducts are sometimes left in contact with the ground causing heat loss and local condensation. Heating ducts should always be off the ground and strapped to the floor joist. This increased moisture is also enough to attract termites.

Exopest can simply install eco-friendly, solar powered sub-floor ventilation systems. The difference is immediate, the energy running the system is free from the sun resulting in a damp free environment and no carbon emissions.

Exopest recommends improving sub floor ventilation particularly where the building has a damp problem under the floor. Often people look at the air vents and assume the vent is working efficiently. This is often not the case. Good subfloor ventilation improves the health of the occupants by reducing airbourne fungal spores.

Old style Terra Cotta vents in double brick homes are notorious for being partially blocked or in poor working order. There are only 15 small holes in each terra cotta vent, each one the size of your little finger! Loose mortar falls down the cavities during building construction; debris and dirt accumulate in the vent over the years and gradually block up the opening. Often there is no opening at all behind the vent, only a brick wall. Exopest recommend replacing the terra cotta vents with the high air flow Aleta vents. They are the same size, but 6 times the air flow and easy to install.

Old terracotta vents
With a brick veneer home on a timber suspended floor we often find the metal air vent is blocked behind by the floor bearer because the vent is positioned too high on the external wall. Also the practise of using 'slit bricks' (Bricks on their side with a gap between) rather than the builder installing proper air vents is not recommended as the small opening between the bricks easily blocks up. This situation can easily be fixed by knocking out the bricks and installing high air flow Aleta vents (See photos below)

Aleta Vents
Moisture attracts foraging worker termites so to counteract this Exopest uses solar powered electric fans and air vents to maximize subfloor air flow. Subfloor fans and vents also reduce mould and fungi growth (See photos below) under the floor and discourage foraging termites and borer attack.

Solar Powered Electric sub Floor Fans
A small solar panel (400mm x 400mm) is mounted on a North or West facing roof and connected to the fan unit in the external sub floor wall. The fan unit is only the size of a normal house brick, but moves about 2500 litres of air a minute. Solar fans are very quiet and efficient requiring no electrician or expensive timers; saving money and power. More importantly the fan only switches on when the weather conditions are right. On wet damp over cast days when the humidity is high the fan does not operate; compared to old style electric fans on timers which come on in all weather conditions. Solar fans are normally installed in pairs, one actively pushing air under the house and the other extracting air. Solar fans require very little maintenance and run for years. Simply wipe over the solar panel a couple of times per year or arrange for the Exopest Fan maintenance service.

Good subfloor ventilation also reduces the chance of attracting other wood eating insects, such as the furniture beetle (Anobium Borer) and termites. Anobium borer infests softwood Baltic pine flooring. Refer to the Borer or Termite Information page for more info.