Cellar renovations are hugely popular at the moment. More and more people want to use their cellar rooms as additional living space. By systematically modernising your cellar, you not only gain a great deal of space, you also increase the value of your home. Abundant light is the key to ensuring a comfortable living environment in the long term. And the advanced ACO system solutions with ACO ancillary room windows provide the answer. These practical windows can be used in various locations, not just in the cellar.