Platform on new construction, renovation, restoration and transformation
An existing building in Amsterdam, currently occupied, is being fitted with an extra floor. At Jurriëns Midden, they don't bat an eyelid at this kind of project. “It's a challenging puzzle, but so far everything is going well.”
The building on Lowaard in Amsterdam-Buitenveldert is owned by the Elisabeth Otter Knoll Foundation. This foundation was originally set up to provide housing for ‘decent ladies who, through no fault of their own, are unable to support themselves’. The building now houses elderly people who can make use of care if necessary. “Due to the housing shortage for elderly people, it was decided to extend one of the existing wings with an extra floor containing nine apartments,” says project manager Derk Westland of main contractor Jurriëns Midden. “The initial plans were drawn up about four years ago, and we were able to start in March 2025. We are building fairly quickly: the timber frame construction is being made in the factory and the facade elements are being delivered to the construction site complete with brick slips, window frames, and glass. Most of the work will be in the finishing stages. Completion is scheduled for week 46.”
The residents, single people and couples aged between 70 and 100, can remain in their homes during the construction work. This requires clear communication. “In addition to adding the extra floor, we are going to replace the central heating boilers and flue gas ducts in all existing apartments. This means that all homes and residents will be without central heating for two days. We deliberately chose to do this during the summer months to limit the inconvenience, but it is quite a challenge. We provide our weekly schedule with an indication of the expected noise nuisance. The foundation can then coordinate outings, for example.”
A new elevator will be installed to access the new floor. This required the construction of an additional elevator shaft. The building dates from 1975 and the foundation was designed to accommodate the additional floor, Westland explains. “We didn't have to do anything to the existing foundation, except build an additional foundation for the elevator shaft. Working with lighter, wooden elements makes a huge difference in terms of weight.”
Building on a ‘postage stamp’ in Amsterdam requires tight planning and a comprehensive transport schedule. The municipality of Amsterdam issued a temporary permit for the use of three parking spaces in front of the building. All prefabricated elements had to be delivered and hoisted onto the roof within four weeks. “During the hoisting, residents were not allowed on their balconies, no matter how warm it was. We didn't want to cause an unsafe situation. Furthermore, we built largely without scaffolding. We connected the old to the new from an aerial work platform. Everything has gone well so far, although we did have some problems with leaks. This was particularly annoying for the residents, but we were able to remedy most of it with pumps and we are now watertight. This project is a challenging puzzle, because we have to take many things into account, such as logistics and safety. But so far, everything is going well.”
