SPACE4free - Retrofitting souterrain areas in 19th century townhouses to apartments with high quality of life and low energy consumption

Planning of durable and damage-free apartments with high quality of life and low energy consumption in moisture exposed souterrain areas of 19th century townhouses. Using innovative ventilation control systems comfortable room climate will be created. Additionally the tolerance of different types of use is ensured. A planning tool enables the scaling of the findings and thus the applicability to various planning situations.

Short Description



Starting point / motivation

Concerning the issues of raising efficiency and conserving resources, the conversion of unused ground floor zones and basement areas into living spaces with high quality of life is a significant contribution to inner-city redensification. In many cases, basement flats are affected by mould and unsanitary conditions, and are subject to a low living standard. Ascending wall moisture and salt efflorescence make permanent occupation impossible in many places. By applying targeted ventilation and aeration as well as a specific ventilation control, it is possible to lower the inside air humidity in basement flats and create a comfortable, high-quality indoor climate.

About a fifth of the existing buildings in Vienna were built before 1919. Approximately a quarter of these are classical late 19th century houses with basement areas with a potential for redevelopment, whereby roughly 16,000 housing units can be developed. This number illustrates the potential for conserving resources.

At the same time it can estimated that the heat demand of a renovated basement flat corresponds roughly to the losses of heat through the basement ceiling of an unrenovated late 19th century house. It thus becomes clear that the heating demand of the entire building is not changed by conversing the basement area and adding extra housing units.

Starting point / motivation

In the project submitted, humidity balances and emission profiles for diverse usage situations are drafted using component measurements. Based on the measurement results and considering assessment criteria of structural engineering and economy, various renovation strategies based on usage are construed.


At the research, project's core is the development of a control algorithm for ventilation systems with which controlled ventilation and aeration depending on the outdoor climate and the user-based requirements is possible. The concept will be verified extensively on a test object and is subject to long-term monitoring. Parallel to this, component measurements are carried out in order to be able to quantify the moisture entry in basement areas.

Expected results

The research project's goal is to enable the planning of damage-free basement flats with minimal energy consumption and high quality of living as well as a high tolerance to different usages. Using planning tools the ventilation control can be gauged to any building structure and provide an ideal renovation strategy for every individual basement area.

Project Partners

Project management

Technische Universität Wien, Institute for Building Construction and Technology, Research Centre of Building Physics and Sound Protection

Project or cooperation partners

Gassner & Partner Baumanagement GmbH

Contact Address

Technische Universität Wien
Institute for Building Construction and Technology, Research Centre of Building Physics and Sound Protection
Tel.: +43 (1) 58801 206 02