Scaffoldless built apartment complex 'TwoTwoFive' in Amstelveen

In Amstelveen, an outdated office building has made way for the construction of the sustainable apartment complex 'TwoTwoFive'. Thanks in part to the decision to build without scaffolding, the first residents will be able to move into their new apartments before summer.

Project developer and investor Forum Amstelveen Invest asked Heddes Bouw & Ontwikkeling some three years ago to carry out the construction work of a new apartment complex at 225 Biesbosch in Amstelveen. After establishing the most suitable construction methodology and optimizing the preliminary design of the new residential building, the North Holland-based construction company first set to work on the three-story parking basement in early 2020. "For this parking basement, we used underwater concrete," says Piet Wever, project manager at Heddes Construction & Development. "We chose this methodology because of the deep location of the basement. Due to the low location of Amstelveen, the groundwater pressure and the groundwater level are relatively high and this creates a high upward pressure. For the building itself, which has a foundation on steel, we devised a springy construction: the tension piles were given a double function. As soon as there is more upper load of the building on the foundation, the tension piles turn into a springy pile. This contributes to less settlement and deflection of the slab foundation."

After completion of the basement, Heddes continued construction on the eighteen-story complex with a total of 276 rental apartments. "In consultation with architectural firm OZ, we carried out the complete direction for the construction and realization of this residential complex," Wever indicates. "This means that we ensured that the installations were worked out and drawn in and that we included the subcontractors in this at an early stage. In this way, we ensured that the project could be realized within the specified time and costs." Among other things, the residential building has an installation with thermal energy storage, so that it is heated and cooled with soil energy. This is done in combination with solar panels. Furthermore, all apartments are equipped with a high efficiency heat recovery system through a CO2-controlled ventilation system for the indoor climate. 

Scaffoldless

To meet the set construction deadline, Heddes Bouw & Ontwikkeling chose to build the floors without scaffolding. "On the construction site itself, there is not much space for the placement of scaffolding and they would be on the deck for too long, which means that the layout of the site cannot start until much later. This is why we chose to provide fully customized elements and balconies for each layer, which are all completely equipped with balustrades, glass and frames," Wever explains. "These prefabricated elements are delivered complete on site, after which we install them using hoistable scaffolding placed on the balconies. In this way, we can see the building come out of the ground step by step, ready-made."

It was the first time Heddes Bouw & Ontwikkeling opted for scaffoldless construction. And apparently successfully, because the company has since applied this method of construction to another project in Amsterdam. "By building without the use of scaffolding, we need less construction time," says Heddes. By mid-March, the construction of the facade was finished and the company continued with the finishing of the homes and the connections of the sewer system, utilities and the layout of the roof garden on the basement roof. The first residents are expected to be able to move into their new apartments before the summer of 2022.