Demountable precast concrete elements for sustainable office building

In Hendrik-Ido-Ambacht, a sustainable and fully demountable office building for Persy Control Services will soon rise. For reasons of sustainability and reuse of materials, no sealant or PUR is used throughout the building. Preco's precast concrete elements are also demountable and can eventually be dismantled and used elsewhere.

The new building has two office floors, a semi-underground car park and a roof terrace. Contractor on duty is Van Baaren Aannemers of Schoonhoven, which engaged Preco for the demountable concrete support structure. "The building will be constructed from a steel structure in the parking basin with a CLT timber main bearing structure above it combined with a core of precast concrete walls," explains Stefan Jongewaard, project manager at Preco. "What is special about this project is that it is being constructed completely demountable, like a meccano package. Putty or PUR are therefore out of the question. The building must be able to be unscrewed, so to speak, and reassembled in another place."

33 precast concrete elements

The core of the new building is formed by 33 precast concrete elements from Preco. "For the basement basin, we delivered and produced 14 elements. In close consultation with the contractor, the positions of the studs were determined and cast along with the foundation," says Jongewaard. "The recesses were then prepared in our elements so that they could be anchored to the foundation via a dry connection. The wall elements among themselves were also anchored with bolts. Also included in the concrete elements are the anchoring provisions for the first floor. And so the building is constructed like a meccano package. For the first floor we supply and produce 9 elements and for the second floor another 10 elements, including 1 cover plate for the elevator core."

215 tons

The total project amounts to some 215 tons of precast concrete elements for Preco. "Not so much a big project for us, considering that we also produce and supply elements for large distribution centers, but that doesn't make it any less special," thinks Jongewaard. "Of the 33 elements, not one is identical. The walls are finished with chipboard on the pouring side and equipped with all the necessary openings and fasteners. Special attachment plates were also provided in several elements for coupling with the steel structure." The biggest challenge, according to Jongewaard, was to ensure that the engineering process was complete before the basement foundation was poured. "This in order to take over the anchor positions correctly. To this end, the engineering of the basement elements was brought forward. These elements were also produced first."

The contractor is now busy "assembling" the shell, as the CLT and steel structure will also be delivered prefabricated. The office building is expected to be completed by the end of this year and will soon be sustainable in use with a roof full of PV panels, two heat pumps in the parking garage and triple glazing in the facades.