Some people find it difficult to breathe in environments with a high level of humidity, for instance because they suffer from asthma. Others feel short of breath and begin to hyperventilate, with the result that they feel weak and can no longer concentrate. The right humidity level is very important in our lives, but in most cases we are not even aware of it. There are meters, of course, but no one uses them. By showing the humidity level in colour, we become more aware of changes in the moisture in our surroundings. This enables us to take action sooner. We trust our perception more than we do figures and measuring instruments.

Henry van de Velde Labels 2015

Edition 2015


Moisture-sensitive wallpaper


Design Salvatore Caltabellotta


Fibreglass, copper(II) chloride,


Salvatore Caltabellotta created a wallpaper made of fibreglass that incorporates a layer of copper(II) chloride. If the paper becomes moist, the colour pigments in it change and the wallpaper changes colour. The material can be used in various forms: wallpaper is the most obvious, but it can also be used as a folding screen.

Copper(II) chloride is a chemical compound with the chemical formula CuCl2. It is a light brown solid that gradually absorbs moisture to form a bluegreen dihydrate. Copper(II) chloride is the most common copper compound, after copper sulphate. As humidity rises, the copper(II) chloride turns a light-blue colour. As the humidity falls, it returns to its yellow/brown tint.