Platform on new construction, renovation, restoration and transformation
On Verhulstplein in The Hague, the construction of De Stadhouders is in full swing. The plan includes 3 new, luxury apartment buildings named after the stadholders Frederik Hendrik, Maurits and Casimir. The buildings are being built on top of a shared, sunken parking garage and each has its own character and charm. The forecast at this time is to deliver blocks 1 and 2 in June, with block 3 following in early 2021. De Stadhouders was designed by ELV Architects and Topos Fields. Waal signed for the turnkey new construction. Commissioned by VORM Development and CBRE Global Investors, the Vlaardingen-based construction company is responsible for all structural work, groundwork, building-related installations, finishing and site design.
The eye-catcher of De Stadhouders will be the Frederik Hendrik building (Block 1), which with a height of 50 meters and 15 floors offers space for 57 owner-occupied apartments, 4 penthouses and 42 free-sector rental apartments. The building has a 5-story entrance hall and all owner-occupied apartments have a balcony, terrace or roof terrace. Frederik Hendrik will be connected by an open courtyard to Maurits (Block 2), which contains 6 floors and 88 rental apartments. Casimir (Block 3) will have 8 floors with 20 owner-occupied and 61 rental apartments. Both Maurits and Casimir will have an open ring of galleries on the inside, which will contain the housing entrances. Between Maurits and Casimir an 18-meter high false facade will be realized, which will give the plan a special appearance.
The highlight of De Stadhouders will be the Frederik Hendrik building (Block 1), which, with a height of 50 meters and 15 floors, provides space for 57 owner-occupied apartments, 4 penthouses and 42 free-sector rental apartments.
On June 20, 2018, Waal started construction of The Stadholders. "At the location of blocks 1 and 2, there used to be an office building, of which the 1.20-meter-thick basement floor has been preserved," says Hans Houweling, Major Projects Project Manager at Waal. "A portion of Frederick Henry and Maurits was founded on the old basement floor. The rest is founded on sand. Building Casimir is being built on the site of a former gas station and is also founded on sand. For the foundation, we used, among other things, 1.90-meter-high concrete piles. In addition, we sawed through part of the core of the old basement floor to properly accommodate the loads." A special feature is that an old World War II anti-tank trench (Atlantic Wall) runs underneath the 3 buildings, he says. "We had to make quite a lot of ground improvements in order to be able to build foundations on this."
After placing the concrete piles, Waal created a new basement floor, on which concrete walls and beams with lots of reinforcement were installed. "Then we continued construction according to a wall-width slab construction method. In the process, we immediately included the wooden interior cavity walls. We made the buildings wind and watertight as quickly as possible and applied waterproofing layers in the interim, which allowed us to start the finishing work in the foreseeable future."
The 3 buildings are finished with clinker brickwork. This means the bricks are bricked on their sides, Houweling said. "And that's easier said than done. We carried out several tests, because the facades - in connection with the wooden interior cavity walls - must be able to accommodate a minimum deflection. The bending tests at the TCKI showed that only the bricks from which the sand had been brushed off met the characteristic value. Therefore, all 355,000 bricks had to be cleaned before bricklaying. To speed up and facilitate this process, in collaboration with an acquaintance in horticultural automation, we developed a brick brushing machine with a conveyor belt that allowed one person to brush 1,000 bricks clean per hour." The top two floors of each block feature gray Equitone Natura façade panels. This creates a unified building ensemble, while the various height differences and building widths give each building individual character.
A loft in Frederick Henry building (Block 1).
Building Block 1 and 2 are equipped with a gas connection. Air-conditioning is fairly traditional, with a central heating boiler, radiators, mechanical ventilation units and grilles above the windows. "Good crack sealing results in high airtightness," Houweling says. "In addition, the EPC has been tightened slightly. To meet this, solar panels, among other things, have been applied." The third building block will be completely gas-free. "Because from 3 meters below the current ground level, the soil under the former gas station is contaminated, we had to install and drill out steel pipes 12 meters long before we could drill the wells. In total, we realized about 60 wells 150 meters deep, which provide the building with sufficient heat and cold. Each apartment will have its own ground source heat pump, and solar panels will also be installed on Block 3. All apartments in Block 3 will be energy-neutral or Zero-in-the-Meter upon completion."
Construction is running on schedule, he says. "The entire project has been worked out in 3D/BIM, minimizing failure costs. At Block 3, we even linked the planning and the 3D model. Together with the performers, we worked out a 4D planning, allowing us to complete a complete floor in 2 weeks."
