At the heart of any good front door is its construction. CarbonCore is the world's strongest and only patented construction method developed exclusively for the front door. Carbon fibres are extremely light, stiff and several times stronger than steel, which is why they are used in state-of-the-art aircraft as well as the most prestigious Pirnar entrance doors. They do not warp in the scorching sun or in the coldest winters. As they seal better, there are no draughts. Opening is extremely easy.