A dream environment
Today's real estate owners are facing new challenges; how to respond to the ever quicker changing spatial requirements of tenants and to changes that need to be made when old tenants leave and new ones move in? The integrated flexibility of the building frame and the technical installations play a major role in answering to these challenges. This has been acknowledged and a working solution has been designed and presented by Parma Oy in extensive co-operation with a number of partners. The new solution is based on the ParmaParel hollow-core slab, and involves using voids as adaptable passages for such technical installations as ventilation, plumbing, and compressed air pipes. In September this year, the Parma integrated hollow-core slab received third prize in "The Engineering Design of the Year" -competition arranged by RIL, the Finnish Association of Civil Engineers.
How it all started
"As it often is with the most progressive innovations, this one also had its roots in customer demand", says Mr. Heikki Sarin, Technology Manager at Parma Oy. "When contacted by the builder, we were given three months to design a proposal for a qualifying ventilation slab". "The purpose was to direct the ventilation of the building horizontally into the voids of the hollow-core slabs". "We had by then already designed the integrated hollow-core slabs into which it was possible to place water pipes, plumbing, and compressed air pipes". "The voids needed to be large, and the slab could not crumble or brake". All of this also called for changes in the machinery that was used to manufacture the slabs. For this purpose, Elematic was called upon to customize an Extruder that could produce hollow-core slabs with a thickness of 400mm, a width of 900mm, and sufficient quality and density. However, the utilizing of the hollow-core voids for ventilation was an even greater challenge. Among others, fire safety and emission standards imposed strict requirements on the quality of the slab. In addition, the attaining of sufficient density for the ventilation ducts required special insulation technology.
Life cycle thinking in construction
The developer presenting Parma with the challenge was Senaatti-kiinteistöt, a Finnish real estate company that works in close cooperation with the Technical Department of the University of Helsinki and also rents facilities to the university. It was in fact the building projects of the university that brought out the need for an integrated hollow-core slab, and the concept of using the voids for ventilation purposes was first conceived at the university. Mr. Toivo Vainiotalo is Head of the Technical Department at Helsinki University. "Life cycle thinking in accordance with the principles of sustainable development is vitally important in the construction industry of today", says Mr. Vainiotalo. "Whether talking about residential buildings or office buildings, it is important to be able to implement changes quickly, to reflect the increasingly swift changes in society". "This means that already in the construction phase it must be taken into account that the building will need alteration in the future". "When the partition walls are attached to integrated hollow-core slabs, where all cables and pipes are inside the voids, it is much easier to change the location of the walls, and there is no need to alter the basic framework itself".
In addition to facilitating changes in a building, the use of integrated hollow-core slabs is also more economical on a life cycle scale than implementing traditional construction technology. There are also benefits such as no need for false ceilings, which gives more height to the room, and overall maintainability is much easier.
Although the integrated hollow-core slab has successfully been implemented into a completed building project, there is still much to develop further. There is ongoing research on how to make the inside surface of the voids even smoother, to develop a coating that is thicker than those currently used. Parma is also working on the production process of the integrated hollow-core system, and is attaining type approvals. In the summer of 2004, Parma initiated a 2-year project with the goal to utilize the thermal mass of the building frame for storing heat or coolness, which then can be collected and transferred to an appropriate location. At best the acitve utilization of the thermal mass may lead to separate cooling equipment no longer being needed at all.