The aim of Krapf was to develop an easily slideable, completely sealable glass window system in a glass facade, fitting flush to floors and ceilings, which will provide the highest degree of comfort and meet the highest building and aesthetic standards. Solution: air-lux has used its many years of experience in facade construction, and its experience with metal windows, to develop an innovative large surface-area glazing system that can be fitted into the overall aesthetic characteristics of a building, without sills.

The core property of the air-lux large surface-area is a patented seal. The revolutionary pneumatic, servicing and maintenance-free sealing system is 100% airtight in the inflated state; it opens and closes by means of a special folding, frictionless, mechanism.