Round residential towers Bossa & Nova as capstone of Asia Park

Energy-efficient and gas-free apartments

In the Aziëpark in Haarlem's Schalkwijk district, construction of the two round residential towers Bossa & Nova is nearing completion. One floor was added to the 14- and 11-story towers every 7 working days, including facade closure and placement of the balconies. The 142 energy-efficient and gas-free apartments have all been sold. The towers stand out with their bronze-colored aluminum facades and spacious balconies.

Commissioned by developer VORM, construction will be carried out by contractor Hillen & Roosen. "We took over the design from VORM and further engineered it, in consultation with Geurst & Schulze Architects. In doing so, we immediately included the wishes of the 142 buyers," said Ronald Brink, project manager at Hillen & Roosen. "Our commitment was to keep the construction cycle per floor as short as possible and to close the facades as quickly as possible."

The towers have a precast concrete core with elevator shaft and stairwell that was constructed per floor in one day. Each floor has 12 segments, 2 of which were tunneled per day. This involved the use of retractable scaffolding. There were no such scaffolds for the two segments opposite, which made it possible to assemble the prefabricated balconies, which were already fitted with railings at ground level, on the facade. After this, the retractable scaffolding was moved for the pouring of the next 2 segments. This work was handled by subsidiary Hillen & Roosen Beton.

Good logistical coordination

The facades are enclosed with an HSB frame and an aluminum façade, components that were manufactured at separate locations and then assembled and transported to the construction site. Says Brink, "This required good logistical coordination with our chain partners, but as a result we were able to complete the shell construction of 2 towers in 35 weeks. Including a wind and watertight facade for the purpose of finishing."

Parking garage

A large 2-story underground parking garage was built next to the 2 towers, good for parking 214 cars. The garage is connected to the towers by a tunnel. Brink: "The towers and the garage are founded on 600 piles and the garage are secured by 500 tension anchors. A constructive challenge was the connection of the garage to the towers, because the towers tend to sink while the garage wants to rise due to the upward pressure. You have to accommodate that dilation." On top of the garage, the Asia Park is now being constructed. The towers are the final piece of the housing development in this new park.

Diversity

Bossa, the tallest tower, will have 78 apartments. Nova will have 64 apartments. With an EPC score of 0.11, the homes are very energy efficient and equipped with a CHP system, optimal insulation and solar panels. The towers offer space for a diversity of target groups. With homes in various sizes, from about 50 to 130 m2, there is room for singles, first-time buyers and people moving on. The apartments have 3 or 4 rooms, a large outdoor space of up to 15 m2, and thanks to the large windows there is plenty of light. They are also equipped with underfloor heating and are delivered with a fully equipped bathroom, kitchen and toilet. The smart ready concept has also been applied. This means that upon delivery, facilities have already been installed to remotely control lighting, heating and security in the future, for example.