Use Case: Closed-Cavity-Fasade (CFF)

Adsorber for Closed System

A CCF facade largely meets the high requirements, in terms of insulating capacity and sound insulation, for modern office buildings. Seasonal temperature fluctuations can lead to the formation of condensate in the closed cavities of the facade. To prevent this efficiently, breathing dryers from GIEBEL® are used. They also ensure that operating and maintenance costs remain as low as possible.

To dispense with the disadvantages of a second-skin façade, the Closed Cavity Façade (CCF) was developed, in which the space between the inner and outer façade shells is completely encapsulated. The “closed chamber” is ventilated with dried and purified air. This prevents condensation or dirt from forming on the condensation or dirt from accumulating on the window panes. Cleaning sashes can be omitted in this way.

Formation of condensate

Throughout the season, the facade is exposed to strong temperature fluctuations. Especially in winter, when the ambient temperature is 0°C and the indoor air is heated by the sun to 20°C, for example, the formation of condensate is pre-programmed. At an average humidity of 50% RH, the air binds 8.6g of water per 1m³.

Since the condensation temperature is already at 9.2°C, a precaution must be taken under these conditions.

Use of decentralized adsorption dryers

The decentralized variant of respiratory drying works with desiccant boxes installed near the facade, for example in the cavity of the floor or ceiling. They must be accessible via inspection flaps for replacement of the desiccant.

Despite the higher installation cost, the CCF pays off compared to a second-skin façade because of the lower maintenance and repair costs. Depending on the volume of the CCF facade, GIEBEL Adsorbers® of the VV-DV series are used. The air drawn into the facade is dehumidified to approx. 2-10%. Consequently, condensation will only occur when the temperature falls below -40 to -12.5°C.