Jedes Bausystem, sei es Massiv-, Holz- oder Fertigteilbau, hat eigene Vorteile und ideale Anwendungsgebiete. Durch die Eigenschaften der VST-Technologie werden viele dieser Vorteile kombiniert, jedoch ohne die vielen Beschränkungen der Systeme zu übernehmen. Dies macht es zu einer einfach anwendbaren, attraktiven und einzigartigen Ortbeton-Bauweise.
Due to the high degree of industrial prefabrication and the elimination of the formwork process (lost formwork: the concrete combines with the formwork elements that become part of the building), the construction time can be reduced by up to 50% compared to other construction methods. The risk of unexpected delays on the construction site, for example due to bad weather conditions, is also minimised. With VST, the completion of a raw superstructure storey only takes 10 days on average.
Direct comparison of the VST system with a conventional construction method
Due to the non-combustible components of the cement-bound flat pressed panels and the concrete core, a rich fire protection interest is provided. Certain of the high fire protection standards are also used as fire protection walls and elevator shafts.
Noise protection is of great importance for people’s health and well-being. The VST technology is a solid construction method with which a jointless structure is produced in the final state. The VST technology has the following sound insulation characteristics:
Overall wall thickness | Thickness of the concrete core | Surface Weight kg/m² |
Extent of Airborne Sound Insulation – CALCULATION- |
Prof. DI Dr. KRAML | |||
175mm | 127mm | 353.50 | 56 dB |
200mm | 152mm | 411.00 | 58 dB |
215mm | 167mm | 445.50 | 59 dB |
230mm | 182mm | 480.00 | 60 dB |
250mm | 202mm | 526.00 | 62 dB |
300mm | 252mm | 641.00 | 64 dB |
Input values:
Density cement bonded particle board > 1,280 kg/m³
Density concrete > 2,300 kg/m³
Buildings constructed with VST technology have high air tightness. The cement-bonded particle boards from which VST products are made have a heat-insulating effect compared to concrete. This allows for significant space and cost savings to be achieved in insulation. In principle, any type of insulation can be used in conjunction with VST products. VST walls (without insulation) have the following thermal resistance:
Overall wall thickness | [m²K/W] | [W/mK] | |
175 mm | 0,240 | 2,440 | |
200 mm | 0,251 | 2,377 | |
215 mm | 0,257 | 2,341 | |
230 mm | 0,264 | 2,305 | |
250 mm | 0,272 | 2,260 | |
300 mm | 0,294 | 2,154 |
24 mm cement bonded particle boards have a thermal conductivity coefficient of 0,26 W/mK and a R value of 0,092 m²K/W.
To calculate the U-value, an exterior wall is assumed – and 0.04 + 0.13 = 0.17 m²K/W (according to DIN EN ISO 6946) is assumed as the rated values of the heat transfer resistances.
VST elements are delivered to the construction site and, according to customer requirements, already include reinforcement and all necessary pipework (empty electrical pipework including electrical sockets, heating and sanitary pipework, ventilation pipework). As a result, many work processes are transferred to the manufacturing plant, where they can be carried out more efficiently under optimum working conditions. On the construction site the VST elements only have to be assembled and concreted.
By relocating many work steps into the secure environment of the VST manufacturing plant, site safety is increased. Fewer staff and tools are required for assembly, which considerably simplifies compliance with the minimum distance and the prescribed hygiene measures and reduces the risk of infection from COVID-19 on construction sites. In addition, the comparatively early installation of VST staircases enables good accessibility to every floor without the use of ladders. Due to the high degree of prefabrication of the VST technology, construction site waste is avoided (e.g. formwork panels, cutoffs, packaging material, etc.).
VST products are compatible with other construction methods. For example, parts of the load-bearing structure of a building can be constructed with VST products and other building parts with precast concrete or in-situ concrete. A combination with timber construction components is also possible.
VST-elements are concreted on site and have a relatively low weight. A VST-wall weighs only approx. 70 kg per square metre (without reinforcement). In comparison, a precast concrete double wall weighs around 300 kg per square metre. Due to the low weight, handling in the assembly process is facilitated and cheaper cranes with a lower maximum load can be used. This means that the site equipment requires less space, which can be a major advantage when space is limited in urban development. The transport costs of VST products to the construction site are also significantly lower than for precast concrete elements. Up to 190m² VST walls or 480m² VST ceilings can be delivered per truck.
When using VST technology, the customer is not bound to specific design specifications, but can freely design the project according to his own ideas. The VST products are produced and delivered precisely to the customer’s specifications. Even difficult architectural design elements such as curved walls can be easily implemented with VST technology. Buildings erected with VST technology have been awarded architecture prizes.
It is our concern to reduce our ecological footprint. An important step in this direction was the passive house certification of the VST construction system in 2008. Passive houses fall into the category of sustainable construction and require around 75% less heating energy than low-energy houses. The use of VST products can make it considerably easier for building owners to achieve sustainability certificates (e.g. LEED, BREEAM, etc.).
VST buildings are massive reinforced concrete structures, which in addition have a monolithic concrete core (i.e. the concrete core extends seamlessly throughout the entire building). This is not only an important factor for high air tightness and energy efficiency, but also increases the stability and thus the resistance of a building to natural disasters such as earthquakes or tornadoes.
The basic product of VST elements, the cement-bonded particle board, has a high PH value of approx. 12, which excludes mould growth. This means that VST products can also be used in wet rooms. Due to the cement content in the boards, VST elements are absolutely resistant to termites and pests.
The VST-elements have a smooth, ready-to-paint surface. A full-surface filling or plastering can therefore be omitted. Only in the area of the panel joints a painter’s structure (filler, reinforcement, primer, paint) is to be applied.
Due to the relocation of work steps to the VST plant, these no longer have to be carried out on site. Due to the shorter construction time, the costs for site maintenance are reduced.
The number of workers required on the construction site is also considerably reduced, which is becoming an increasingly significant advantage due to the shortage of skilled workers and rising wage costs. For example, a VST assembly team consists of only 5 people.
Furthermore, the high energy efficiency of VST buildings saves operating costs.