Increasing airtightness in modern buildings is creating a growing moisture management risk that is not always addressed in design, says air treatment technology specialist Solenco.

Buildings are becoming more energy efficient and tightly sealed to reduce energy loss and improve climate control. However, this limits natural airflow, which has historically assisted with moisture management, notes Solenco commercial sales manager Wynand Deyzel.

Green building standards are driving tighter building envelopes and improved insulation, with older buildings being retrofitted to improve energy performance. However, coastal regions, such as parts of the Western Cape and KwaZulu-Natal, continue to experience high ambient humidity, and all of these ‘green’ improvements are being undertaken without fully considering moisture behaviour in sealed environments, says Deyzel.

This has resulted in a mismatch between temperature and moisture control.

While buildings may feel cool, often they still retain high humidity levels, which can affect materials, finishes and equipment over time. Persistent moisture can lead to corrosion, surface degradation and higher maintenance requirements, particularly in consistently humid conditions.

Deyzel stresses that moisture control must become a design consideration.

He explains that standard heating, ventilation and air conditioning (HVAC) designs do not fully address moisture, even while ventilation and acceptable indoor air quality standards, such as ASHRAE 62.2, set minimum requirements. These standards recognise that natural airflow is no longer sufficient in tightly sealed structures, but ventilation does not actively control humidity, particularly in humid climates.

Air-conditioning systems remove some moisture during cooling but are not designed to control humidity directly, as they operate based on temperature settings. By contrast, Deyzel says that dehumidifiers are designed to regulate moisture independently of temperature, making the two systems more effective when used together.

This is leading to increased use of integrated dehumidification systems, which are being specified to maintain stable indoor conditions, reduce strain on HVAC systems and support long-term asset performance.

For developers and facility operators, this applies to both new builds and retrofits. Ceiling-mounted, inverter-driven systems can be included in design plans or added to existing buildings to manage humidity consistently without affecting aesthetics or energy performance.

As buildings become more efficient, Deyzel states that moisture management is shifting from a passive outcome of ventilation to an active design requirement that will influence building performance over time.