From Factory to Construction Site in Record Time
Interview with DI (FH) Michael Schranz, Managing Director, and Günther Greistorfer, Authorized Officer of G.V. Haustechnik - Installation and Service GmbH
Efficiency, quality, and sustainability - three keywords that are not empty promises at G.V. Haustechnik - Installation and Service GmbH, but lived practice. As the youngest member of the Handler Group, the company has quickly earned a pioneering role in large-volume residential construction – through radical prefabrication and series-close building, combined with tailor-made technology and solid engineering.
Wirtschaftsforum: Mr. Schranz, Mr. Greistorfer, G.V. Haustechnik is a relatively young company in the Handler Group. How did it come about?
Michael Schranz: Building services engineering has been a strategic issue for us as a general contractor for a long time. We wanted to extend the value chain internally and at the same time deepen our expertise in sustainability and hybrid construction. The decision to integrate our own building services engineering firm was a deliberate one – it was intended to contribute with its know-how to the overall orientation of the group. G.V. Haustechnik thus optimally complements our philosophy of systemic and sustainable construction.
Günther Greistorfer: We see ourselves as an engineering service provider, not a traditional installation company. This means: We accompany projects from the start conceptually and bring our planning competence and system solution into every phase.
Wirtschaftsforum: What specifically differentiates you from other providers in the market?
Michael Schranz: Our unique selling point is clearly the consistent prefabrication. We transfer industrial principles to the construction world - that means: as many elements as possible are not made on the construction site, but are prefabricated under controlled conditions in the factory. This way, we can build faster, more precisely, more resource-efficiently, and with higher quality. This is not only efficient but also a clear signal towards the future of construction.
Günther Greistorfer: System construction is our core. For example, we manufacture complete riser ducts in the factory - to precise measurements, standard compliant, and exactly coordinated with all trades. This eliminates classic problem zones at the construction site: no open shafts, no offcuts, no delays.
The result: When the shell construction is completed, up to 90% of the heating and 80% of the plumbing technology has already been installed. This not only significantly reduces the construction time, but also ensures consistently high quality of execution.
Wirtschaftsforum: What advantages does this provide to your clients?
Günther Greistorfer: In addition to time savings and planning stability, our partners benefit mainly from reliability. Prefabrication means: fewer interfaces, fewer surprises. Everything is planned in advance. Coordination is completed before the first component arrives at the construction site. This also allows us to efficiently realize consistent floor plans – a huge advantage for projects of 100 residential units and upwards.
Michael Schranz: Another point is the optimized use of space. Through our prefabrication strategy, it is possible to integrate technical systems in a space-saving manner. For investors, this means: more usable area, economically more functional space - while maintaining the same functionality.
Wirtschaftsforum: Is prefabrication for you just a means to an end or a fundamental corporate philosophy?
Michael Schranz: For us, it is a strategic cornerstone. Prefabrication allows us to achieve sustainability, quality, and cost-effectiveness simultaneously. We do not claim to sell a rigid system—quite the opposite. We respond flexibly to customer requests, but offer a technologically sophisticated and economically attractive structure. This only works when involved early in the project development.
Günther Greistorfer: Exactly. In practice, this means that we provide advisory support already during the tendering phase. We often completely revamp conventional approaches, develop a new prefabricated concept, and support the client until implementation. This early integration is one of our greatest strengths.
Wirtschaftsforum: What role does sustainability play in your approach?
Günther Greistorfer: A central one. By having a high degree of pre-fabrication, we reduce waste, avoid unnecessary transports, and lower the error rate. At the same time, we rely on modern energy systems such as geothermal, heat pumps, or component activation. Flagship projects like Käthe-Dorsch-Gasse 17 in Vienna show that this combination of technology, planning depth, and sustainability works – and is also economically convincing.
Wirtschaftsforum: Finally: Is G.V. Haustechnik the model for the construction of tomorrow?
Michael Schranz: I would say: Yes. Not in the sense of One Size Fits All, but because we demonstrate that high-level pre-fabrication and individual architecture do not exclude each other. On the contrary – they complement each other. Our vision is to implement the diversity of modern architecture efficiently and sustainably with a few, well-coordinated systems.
Günther Greistorfer: And that's exactly what makes our job so exciting – we shape the future with a system.