Gründerzeit with future - demonstration project 3: KA 7 Kaiserstraße - Innovative renovation of a listed Gründerzeit building

A demonstration of how innovative measures, with highly efficient and contemporary standards and taking into consideration comfort and energy consumption, can be applied to a heritage listed building.

Short Description

This project is a sub project of the flagship project "Gründerzeit with future: Innovative Modernisation of Wilhelminian style "Gründerzeit" Buildings"




Point of Departure/Motivation

The renovation demonstration project along Kaiserstraße 7 in Vienna's 7th district is a monastery building owned by the Congregation of the Mission of St. Vincent de Paul (also known as Vincentian Fathers and Brothers or simply Lazarists). The site is situated opposite to Westbahn­hof train station. The building was constructed in 1904 as a part of a court ensemble composed of The Immaculate Conception Church and a residential monastery building facing it. The whole court ensemble is under heritage protection.

As a part of the flagship project "Gründerzeit mit Zukunft" (Gründerzeit with a future), the building owner modernises Kaiserstraße 7 with an innovative, future-oriented and sustainable manner instead of only investing in the upkeep and asset maintenance of the building.

Project Scope and Objectives

Befor the renovation, the building had about 1.935 m² of useable space. After its renovation and the loft conversion, an approximate total of 2,750 m² of floor space was generated.

A great balancing act between heritage preservation measures and an architecturally optimal thermal insulation was asked since it allowed the Congregation to have an economical and social utilisation of the whole building complex. Through the innovative renovation measures, the building standard and comfort were sustainably improved and its existing value greatly increased.

The resulting facilities opened up for an expanded group of users in symbiosis with the existing building usage. The innovative solutions, adapted to the specific situation of the site, are intended to be used as a basis for the future renovation of Gründerzeit and listed buildings and would thus create an interesting contribution to the evaluation and standardisation of thermal insulation solutions.


Due to heritage conservation requirements, the traditional method of thermal insulation in renovation projects is inadmissible. The following strategies were put into place to achieve a high-efficient thermal insulation.

  • The outer window sash of the Viennese "Kastenfenster" on the heritage protected facades were kept and renovated. The inner sashes are complemented with passive-house standard wooden windows in the same fashion as the Kastenfenster.
  • Energy requirements were reduced on the listed facades through the application of internal insulation.
  • Use of a central ventilation system with heat recovery in all living and lounge areas.
  • Static-reinforcement and thermal insulation of the roof while maintaining the existing roof geometry along the heritage protected facades.
  • The courtyard facade, the building's extension and the fire walls were renovated with high-efficient thermal insulation.

Status quo

The project was completed and was turned over to the users. All renovation measures were implemented as far as possible according to the project plan with minor variations. All interior and competition works were completed. The actual energy performance was established.

The sensors for monitoring and analysis in the equipped flats are continuously gathering data.

Future Actions and Steps

  • Completion of the sanitary and HVAC systems
  • Completion of the interior works
  • Construction end by May 2013
  • Application of a blower-door test
  • Establishment of the building's actual energy performance
  • Monitoring and evaluation of the sensor-equipped apartments


  • The innovative measures were professionally executed
  • The heat demand stays between the calculated heating demand which would reflect lower operational costs
  • A high level of user satisfaction achieved through the improvement of the comfort levels and indoor climate
  • Kaiserstraße 7 serves as an example for future renovation projects of heritage preserved Gründerzeit buildings

Project Partners

Project management

Kongregation der Mission vom heiligen Vinzenz von Paul (Lazaristen) Pater Mag. Eugen Schindler CM

Project or cooperation partners

Architekt Kronreif_Trimmel&Partner ZT Ges.m.b.H.

Contact Address

Architekt Kronreif_Trimmel&Partner ZT Ges.m.b.H.
Arch. DI Günther Trimmel
Johann Hörbiger Gasse 30
A-1230 Wien
Tel.: +43 (1) 889 3079
Fax.: +43 (1) 889 3079 212