Concrete spiral staircase
When faced with the challenge of renovating a spacious, semi-detached villa in Amsterdam, architect Siebe Tettero decided to remove the large, but dark stairwell at the heart of the house. He replaced it with a design that both maintained vertical circulation and allowed daylight to pour through the 5-floor home. In line with the highly monolithic interior design, HPC (high-performance concrete) was chosen for the staircase in the new stairwell.
From design to production process.
Apart from creating the design, manufacturing and installation played a significant part in the design process. Together with Verhoeven Timmerfabriek/Mammoet Nederland, manufacturer mbX contributed considerably in the preliminary stages of the creation of the staircase. The stair elements were produced under controlled conditions. The mixture was fine-tuned to guarantee an ultra-white surface. The decision was made to strive for a high-quality finish, while accepting surface imperfections caused by trapped air bubbles as an expression of the specific and complex production process.
In the preparatory stages, we were involved in planning the dismantling and installation on site. All the required hoists were integrated. The stairs were poured upside down and subsequently dismantled and turned over by Mammoet using their own bespoke turning frame/mechanism. The staircase was then transported to the site with a custom-made transport frame. The process from dismantling to installation was included in the parametric design in the construction design phase. The stairs all had to be lifted in through an opening in the roof. The stairs leading from the ground floor to the first floor were a particular tour de force. Due to the maximum opening and the oversized staircase, the stairs had to be turned through the roof. It was a huge challenge which was completed successfully.
Nomination for concrete award
This project was one of three nominees for the 2019 concrete award in the Residential Construction category. The jury commented: "It is a feat of engineering. It is an impressive achievement and a demo project with the potential to be scaled up."