Overview
Ensuring proper humidity control in housing, especially during winter, can be challenging due to varying air leakage, frequent door openings, and the use of showers. Winter design performance is crucial to prevent condensation on critical surfaces like glass. Desiccant dehumidifiers are highly effective in cold climates as they don’t rely on condensation to function, making them ideal for humidity control in such conditions.
Regulatory Considerations
Australia’s National Construction Code (NCC) 2022 includes provisions to reduce condensation risks in new homes. To select appropriate equipment, the DA07 AIRAH design guide for critical moisture analysis should be applied. This guide provides performance-based criteria for predicting, mitigating, or reducing moisture damage to the building envelope and interior components.
Typical DA07 Selections
2 Bedroom Sealed House
- DA07: 9L/day = 0.375L/h
3 Bedroom Sealed House
- DA07: 10L/day = 0.416L/h
2 or 3 Bedroom Selection
- DC5 Summer: 20°C 50% RH, 0.5L/h
- DC5 Winter: 10°C 50% RH, 0.40L/h
4 Bedroom Sealed House
- DA07: 11L/day = 0.458L/h
4 Bedroom Selection – DST Models
- DC10 Summer: 20°C 50% RH, 0.58L/h
- DC10 Winter: 10°C 50% RH, 0.44L/h
- DC10 Winter: 0°C 50% RH, 0.25kg/h
Refrigeration Option – Summer Only
- Summer: 20°C 50% RH, 0.50L/h
- Winter: 10°C 50% RH, Refrigeration is non-operational
The DST model DC5 or DC10 is suitable if leakage is contained to levels estimated in DA07. These units can be ducted to multiple rooms with a common return location, providing a solution compliant with building code moisture requirements.


Additional Considerations
Underfloor “Crawlspace” Units Used frequently in Europe, these units may be a viable solution, provided there is adequate ventilation.
Commercial Airflow Installation Each crawlspace installation is unique and may require professional installation. The diagram illustrates a typical setup, while the accompanying photo shows a Seibu Giken DST dehumidifier installed in a crawlspace.

Energy Consumption To minimize energy use, a hygrostat (humidity sensor) should control the dehumidifier. The hygrostat activates the dehumidifier when humidity levels are high and turns it off when they are low. A control box with a warning lamp can be connected to the hygrostat and installed prominently inside the house.
Contact Us
For more information or assistance with your dehumidification needs, feel free to reach out to our expert team.
FAQ: Dehumidifying Your House in Winter with Desiccant DST Dryer Dehumidifiers
How to dehumidify a house in winter?
Using a desiccant dehumidifier, such as those offered by Desiccant DST Dryer, is highly effective for winter dehumidification. Unlike traditional dehumidifiers, desiccant dehumidifiers do not rely on condensation to remove moisture, making them efficient even in cold temperatures. They absorb moisture from the air through a desiccant material, ensuring your home remains comfortable and dry.
Should you dehumidify in winter?
Yes, dehumidifying in winter is essential to prevent condensation, mold growth, and structural damage. Even in cold weather, moisture can accumulate from daily activities like cooking, showering, and breathing. Desiccant DST Dryer dehumidifiers are specifically designed to operate efficiently in lower temperatures, making them an ideal choice for winter dehumidification.
Do you need a dehumidifier in the crawlspace in winter?
Absolutely. Crawlspaces are particularly prone to moisture buildup, which can lead to mold growth, wood rot, and structural damage. Using a desiccant dehumidifier from Desiccant DST Dryer in your crawlspace will help maintain low humidity levels, protecting your home’s foundation and ensuring a healthier living environment.
What should house humidity be in winter?
In winter, the ideal indoor humidity level should be between 30% and 50%. This range helps prevent condensation on windows and other surfaces, reduces the risk of mold growth, and maintains comfort. Desiccant DST Dryer dehumidifiers can effectively manage humidity levels within this range, ensuring optimal indoor air quality and comfort.