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Solar Sub Floor Ventilation

How do you get rid of mould and condensation?

Chances are you haven’t checked your subfloor space in a few years. If you have problems with mould, moisture and condensation anywhere in your home, it might be a result of poor subfloor ventilation!

Sub floor ventilation fans

A subfloor (or underfloor) is liable to get damp & musty if left unchecked. Without sub floor ventilation, you risk:

  • Mould, mildew or fungal growth,
  • Rising damp & condensation problems,
  • Rotting floorboards & foundation stumps,
  • Damage to internal walls & paintwork,
  • A perfect breeding ground for white ants, termites & borers!

High moisture levels can lead to irreversible damage to the structure of your house. Repairing your subfloor space is no cheap fix—so why risk having problems in the first place? If you have high humidity and poor indoor air quality, you’re risking the health of the home occupants.

Solar Whiz offers powerful solar sub-floor ventilation. We’re serious about protecting & safeguarding your home’s subfloor. Don’t risk your greatest investment becoming an expensive repair job—no home subfloor should be a problem.

How does Sub Floor Ventilation work?

Solar Whiz offers a wide variety of solar subfloor ventilation fans, each suited to extracting different volumes of air. Every home is different—some large, some small, some with lots of subfloor space, and some with none at all!

We offer a variety of solar underfloor fans, each of different sizes and ventilation capacity. We understand that subfloor vents need to cater to a wide variety of homes. In the scenario one of our fans doesn’t fit, we can also make use of our other inline fans to tailor a subfloor vent solution just for you!

Our subfloor fans are connected to roof (or even wall-mounted) Solar PV cells. These ensure that your subfloor ventilation system runs when you need it most, and can even run in low-light conditions like overcast weather! If a Solar-style setup doesn’t suit, we can even set up a 12-volt power pack plugged into a 240-volt powerpoint for underfloor ventilation all day long.

Currently, some of the Solar Whiz Sub Floor Ventilation fans that we offer are:


Model SW-AU-W-40 SW-AU-W-28 SW-RAF-G-2100 SUB2100G
Capacity 2,500 m³/h 2,000 m³/h 2,100 m³/h 1,400 m³/h
Fan Motor 10-26 Volt DC Brushless motor with double-shielded ball bearings
Fan Decibels <55 dBA <45 dBA <60 dBA <45 dBA

Height: 147mm

Diameter: 360mm

Height: 147mm

Diameter: 360mm

Height: 185mm

Diameter: 500mm

Height: 230mm

Diameter: 650mm


These sub-floor fans are set up to draw air through subfloor vents set up around your subfloor. Depending on the home, we can offer a variety of installation methods to achieve the results you need. If you have a brick subfloor with little to no air intakes, we can map airflow through your subfloor space. We can duct, or we can even extract air through the roof via a roof-mounted Solar Whiz!

Methods for Sub Floor Ventilation

Sub floor vents help keep your sub floor healthy.

1) Bifurcation

By using a split ducting system, we can create multiple air intakes through your subfloor. This allows the subfloor extractor to draw air from multiple spaces of your subfloor, creating cross-ventilation that covers almost the entire floor space. This is one of our most popular installation methods.



Underfloor ventilation helps you control your sub floor condensation.

2) Single Duct Extraction

A single duct allows you to channel air to specific locations of the house. If a single subfloor vent is installed, it will allow you to draw air from specific regions of the subfloor.




Sub floor vents with Solar Whiz are reliable, and powerful.

3) Roof-Mounted

If subfloor space is too limited, we can also offer roof-mounted subfloor ventilation. By ducting a Solar Whiz roof ventilator down to your subfloor, we can offer powerful extraction that won’t be affected by limited subfloor space.



Under floor ventilation can save your home from expensive restumping.

4) Push/Pull Method

If you have segmented subfloor space, or would like to map & channel airflow through your entire subfloor space, the push/pull method allows you to move air through the subfloor from one end to the other.



Benefits of getting Solar Whiz subfloor ventilation:

Reduces moisture

Solar Whiz subfloor ventilation helps to reduce moisture in your home. By circulating fresh air through your subfloor area, it helps to prevent the buildup of moisture and dampness, which can lead to a range of problems such as mould growth, musty smells, and damage to your home’s structural integrity.

Improves air quality

Solar Whiz subfloor ventilation helps to improve the overall air quality in your home. By removing moist and stale air from the subfloor and replacing it with fresh and drier air and by reducing moisture content under-floor, subfloor ventilation also helps eliminate allergens, dust, and other pollutants inside the house which can cause respiratory problems and other health issues.

Increases energy efficiency

Solar Whiz sub floor ventilation is powered by solar panels, which means it is an environmentally friendly and cost-effective way to improve your home’s energy efficiency. By reducing the need for air conditioning and dehumidifiers, subfloor ventilation also helps lowering your energy bills and reduce your carbon footprint.

Pest control

Solar Whiz sub floor ventilation can help to prevent pests such as termites, spiders, and rodents from infesting your sub floor area. These pests often thrive in damp and humid environments, so by reducing moisture levels, Solar Whiz sub floor ventilation will make your underfloor area less appealing to them.

Enhances home comfort

Solar Whiz sub floor ventilation can also enhance the overall comfort of your home. By reducing moisture and improving air quality, it helps to create a more pleasant living environment that is less prone to mould growth, dampness, odours, and other issues.

Prevents structural damage

Solar Whiz subfloor ventilation helps prevent structural damage to your home. By reducing moisture levels, it helps to protect against termites, rot, decay, and other forms of damage that can occur because of dampness and humidity in the sub floor area. This can help to extend the lifespan of your home and save you money on maintenance and repairs in the long run.

Reduces the risk of health problems

Dampness and mould growth in the subfloor area can lead to a range of health problems such as allergies, asthma, and respiratory infections. By reducing moisture levels and improving air quality, Solar Whiz subfloor ventilation can help to lower the risk of these health issues.

Increases the lifespan of your flooring

Dampness and humidity in the subfloor area can cause wooden flooring to warp, buckle, and rot over time. By reducing moisture levels, Solar Whiz subfloor ventilation can help to protect your flooring and extend its lifespan.

Enhances property value

Installing Solar Whiz subfloor ventilation can enhance the value of your property. Potential buyers will appreciate the benefits of having a well-ventilated and dry subfloor area, which will help prevent future problems and lower the cost of maintenance and repairs.

Easy to install and use

Solar Whiz underfloor ventilation is easy to install and use. The solar-powered design means that it requires no external power source, and the system can be easily controlled with a switch or thermostat. Additionally, it requires minimal maintenance, with no need for regular filter changes or cleaning.

Solar powered subfloor ventilation – more effective than powered

Solar Whiz subfloor fans bring more fresh and dry air into the subfloor on sunny days, therefore, maximising the drying effect – and running slowly on rainy days with high moisture content. On such days our solar-powered subfloor fans will continue to run at full speed, bringing moist air into a (usually) cooler environment. As the relative humidity goes up, this can and will often result in moisture levels in the subfloor going up on wet and cold days, when using powered fans.

What else doI need to know about Sub Floor Ventilation?

If you want your underfloor ventilation to run around the clock (not just when the sun is out!) then a constant current module is right for you. We simply add a module to the pre-existing solar system that allows your subfloor fan to top up power from mains electricity if the solar charge is depleted.

With a reliable Solar Whiz Sub Floor Ventilator, you don’t need to worry about condensation or wet and dry rot. You simply have it installed, and have the peace of mind that your sub floor’s health is in good hands. If you’re interested in finding out more about Sub Floor Ventilation, check out our brochure.


Solar Whiz offers powerful sub floor vents.

Frequently Asked Questions

What is sub floor ventilation?

Subfloor ventilation is the process of removing moist air from your home’s subfloor and replacing it with new, dry air. This is accomplished by adding a number of air vents to the outer subfloor of your home.

Does sub floor ventilation work?

Properly installed subfloor ventilation systems can effectively mitigate rising damp and mould growth. By reducing moisture levels in the underfloor area, these systems help prevent the progression of these issues.

Do I need subfloor ventilation?

Enclosed sub-floor spaces require sub-floor ventilation. Relative humidity in the air increases when moisture evaporates from the soil and is absorbed by the atmosphere above. The moisture content of the flooring and frame members will subsequently increase as a result of this.

How long does it take to run subfloor ventilation?

We’ve discovered that running the fan for about 4 hours a day is enough to keep things ventilated properly. The optimum time to run the fan is typically during the day, when the air is warm and dry.

How many vents should a subfloor have?

A suspended timber-framed floor needs to have ventilation under it. There should be a minimum of five air changes every hour (and double that for wet subfloor spaces). For every square metre of floor area, a clear opening area of 3500 mm2 (100 x 35 mm) should be supplied.