An OWA ceiling is installed using dry construction methods and is generally for interior use only. The basic principles of dry construction should be applied when installing the ceilings. Where additional materials such as timber or gypsum are used, the guidelines on working with those products should also be observed.
Before installing an OWA ceiling the room/site conditions should be assessed. The area should be weather tight (windows and doors in place) and have a stable, dry environment. The ceiling should only be installed after the wet trades, such as plastering and screeding have been completed and the environment is dry and stable.
Reference values for site environments:
Generally the relative humidity should be < 70 % RH (reference temperature 25 °C), For reference values for OWAcoustic® tiles see 3.2; conditions suitable for tradesmen's work, room temperature > 7 °C.
Temperature has a direct correlation to relative humidity. Lowering the temperature in an enclosed space will increase the relative humidity of the area. Where an area may have a high level of relative humidity or be subject to a temperature variations it is important to ensure the area is monitored and if necessary ventilated to remove humid air. This is particularly important in areas where wet trades have been used such as new build projects.
on the relative humidity. This can be understood by considering the absolute humidity (g/m3).
Room temperature 20 °C, absolute humidity at 12.10g/m3 corresponds to a relative air humidity of 70 %.
Lowering the temperature to 15 °C with an associated comparable absolute humidity of 12.23 g/m3 means a relative air humidity of 95 %.