LifeCycle Tower - Energy efficient prefabricated multi-storey timber houses

Based on the results of previous research projects, the project at hand deals with the development of a wooden prefabricated module construction for energy efficient office buildings with up to 20 storeys. This sustainable system ensures cost certainty through the whole life cycle of the building.

Short Description




Starting point/Motivation

The rapid urbanization growth of the next years requires significantly more space in the cities. Buildings are constructed by-and-large in conventional steel-concrete constructions. The increasing shortness of resources as well as increasing prices for raw materials are making wood more interesting as a construction material. Furthermore, (high-rise) buildings also have an untapped potential for energy production and storage. Constructed buildings are usually made as individual prototypes, what causes high construction costs and long planning and construction times. Modular construction types, on the other hand, provide cost security and lead to a significant optimization of quality and economics. All these considerations were the motivator for the creation of a product in the construction business, which can lead to the reduction of dependency on conventional construction materials and energy types. This project is building on the results of prior projects, during which the technical feasibility of a wooden high-rise building have been researched and the initial ideas for durable building developments had been worked out (achtplus, Immo Rate, inkl.wohnen).

Contents and Objectives

The goal of the project LifeCycle Towerwas to develop a flexible, modular, ready-to-build wooden construction system for the construction of energy-efficient office high-rise buildings with up to 20 floors. Additional emphasis was placed on the construction of matching building and facade technology, which also contributes to going from an energy-using to an energy-producing building and thus contributes to a building industry which is CO2-neutral.

During this research project the following main goals were defined:

Development of a ready-to-build, flexible "wooden construction system" (modular construction type):

  • for high-rise buildings of up to 20 floors
  • for use as offices, apartments and/or hotels
  • with the most efficient energy concept possible
  • with a positive energy balance sheet.

The goal of the project LifeCycle Tower is to develop a wooden construction system for the first time as a new, independent product which meets the requirements of fire protection, acoustics and bearing capacity.


An integrated planning process was applied to the entire project, which means that representatives of all areas of knowledge (architecture, static, facility management, building technology, etc.) had worked jointly through the essential tasks. Another central element was carrying out theoretical simulations, which were checked and confirmed with real trials (e. g. fire test).


At the end of the project the following results had been achieved:

  • a comprehensive building concept for construction, building technology and facade
  • a wooden modular construction system as a new, independent product, which meets the requirements for fire protection, acoustics and bearing capacity
  • a product- and manufacturer-neutral building technology-layout incl. facade concept
  • energy design for a plus-energy-house
  • ready-to-file planning for an imaginary location
  • lifecycle-orientated economical calculations
  • a CO2-balance and certification.

The entire building system was geared towards its technical and economical feasibility as well as ecological criteria. Therefore a product was created which is significant and which offers cost security during the entire lifecycle. This was achieved through a modular, wooden construction system type, which can be industrially made and which forms the core structure of an energy-optimized facade system. For this, building technology, facade and construction were forming an interdependent total system.

Prospects / Suggestions for future research

The findings of this research project will be shown as a next step through a demonstration project and shall be further optimized.

Project Partners

Project management

Mag. Michael Zangerl
Rhomberg Bau GmbH

Project or cooperation partner

  • Architekten Hermann Kaufmann ZT GmbH
  • Wiehag GmbH
  • Arup GmbH
  • TU Graz

Contact Address

Rhomberg Bau GmbH
Mag. Michael Zangerl
Business unit development, risk management
Mariahilfstrasse 29, A-6900 Bregenz
Tel.: +43 5574 403-215
Fax: +43 5574 403-99215