The established Danish Timber clad specialists Rational have a keen eye for exciting collaborations, and we are pleased to announce that 1st Folding Sliding Doors are now supplying and installing the Rational range.

Manufacturing timber windows and doors since 1954 their products are known for Combining the products high quality and stringent product guidelines, long service life and it’s sustainable and easy to clean and maintain products. The only significant difference between our aluminium products and the Rational range is that the windows and doors made entirely of timber. The products will have to be painted after some years. Sun rays and wind and weather expose the paint to wear, especially on south facades, and windows and doors should, therefore, be painted approx. Every five years.

To avoid maintaining windows and doors, Rationel Windows has developed several product ranges in bespoke aluminium and timber which minimise the need for maintenance. The constructions consist of an all-timber sash and frame with external alu cladding offering protection against the weather. This means that you do not have to paint the exterior of your windows or doors during the life of the products.