old house? old house!

Motivation

This project conjoins two central themes for the future of sustainable housing development within the European context: Strategies for appropriate, contemporary housing forms for the Aged and the sustainable, ecologically efficient and intelligent renovation of 19th century housing stock.

Ornament and climate protection
Thermal renovation of 19th century housing stock with its largely ornamented facades is no topic to be openly discussed at the moment. Ornament and climate protection seem to contradict each other at the moment.

The quantity of 19th century housing stock in Vienna is not to be ignored (30% of all Viennese apartments date from before world war one. Therefore we consider it essential to initiate the discussion about how to minimize energy consumption on these buildings and to pose an example of how a sustainable renovation could be done and the themes to be discussed.

Contents

The report contains basic research to following themes: constructing for the Aged, living with service, construction and building material of 19th century housing.

Twelve quality criteria have been developed to enable a senior citizen to evaluate a building in the means of adequacy for senior living. 6 general principles of sustainable and energy efficient renovation of 19th century housing stock are proposed, such as the restructuring of the floor plans, implementation of infrastructure, giving the building a new skin, utilization of the attic and the roof, dedicated green space for each dwelling unit. It is shown how these principles are to be realized by the means of design, handicapped accessibility, building services , using floor plans, facades and sections of an existing building. One chapter is addressed to a track without barriers through the whole building, the next chapter shows the details of building services.

The last part of the report addresses itself to the technical realisation with all essential technical details, details of statics, assembly of components, U-values, the calculation of thermal bridges, the "Passivhausprojektierungspaket PHPP", and the simulation of moisture in the basement.

Targets

The project provides a basis for a radically new discussion in urban renewal. Outcomes and solutions can now be implemented on many buildings of the special era. in this way, a pre-condition is set up for a new approach to renovation of 19th century buildings. Likewise a line of reasoning is created for several problems so far inadequately answered.

Methods and data

Basic research has been supported by internet and literature inquiry and our practical experience as architects. Data for living without barrier come from Austrian standard (ÖNORM),Viennese building regulation and a dialogue with an Austrian organization for the handicapped called BIZEPS.

All of the planning was done in form of integrated planning, with discussion and dialogue between all projects partners right from the beginning. The U values have been calculated with the simulation tool "archiphysik", the demand of thermal heat and the heating load have been calculated with the tool PHPP 2004 of "Passivhausinstitut Darmstadt". Statics have been dimensioned by Dipl. Ing. Lutz, the calculation of the thermal bridges has been carried out with the simulation tool WAEBRU 6.0. The simulation of the conditions of the basement has been carried out with the recently developed simulation tool HMS at the technical University of Vienna, Zentrum für Bauphysik und Bauakustik, Institut für Hochbau und Technologie.

Results and conclusions

Service Living for senior citizens
Basically the intended term for an up-to-date senior living - such as self-determination, autonomy, living in an residential setting, being supported by a system of professional care - can be summed up under "Service Living for senior citizens". It is very important to place this "Living with Service" at a central location of the city, because only there the elderly can take part in normal "every-day" life without difficulties. The 19th century quarters of the city of Vienna offer excellent conditions for this kind of setting. It would make sense to renovate a few buildings close to each other at the same time. This would be an economically efficient move to integrate the elderly - without creating an unwanted "ghetto".

Adaption to the needs of the disabled
Adaption to the needs of the disabled means that everyone - regardless of age or handicap - can use all facilities without social or technical segregation. It is important to notice that for senior citizens wheelchair-accessibility is only one aspect out of many whereas it is equally important to avoid anthropometrical, ergonomical and sensorial barriers to give relieve to the "normal" elderly.

Quality criteria
To define quality-components is an important tool to enable users to estimate the value of their (future) real estate. The twelve quality-components listed in this project might represent a subgroup of a general Building-Pass, as has been developed recently. The general evaluation of real estate could be added to by this component for special uses. This would not only support users in taking decisions but also challenge developers to get good evaluations on their buildings. In the long run quality criteria would evoke quality improvements.

Principles of a sustainable, energy-efficient redevelopment
Six principles of a sustainable, energy-efficient redevelopment have been defined for buildings of the19th century: reorganizing the building, new skin, usage of the roof, renovation of the basement, dedicated exterior space, new infrastructure.

Buildings of the 19th century should be preserved because of their high potentials and their spatial and material qualities. But they have to be transformed and reconstructed to match with modern and up-to-date buildings. This transformation is as well technically possible as - in the long term - the only true solution dealing with housing of the 19th century. When renovating these old buildings you must recognize and correct essential defects. Otherwise outdated solutions of a past episode will be preserved for another 50 or 100 years.

• Reorganizing the building
  Analysing the Willhelminian buildings of Vienna, we found out that there are different typologies of buildings with a different need of renovation. For nowadays-standards the typical bourgeois houses need only technical and thermal improvements, while former "working-class" housing called "Bassenahäuser" need much more renovation. They must be addressed much more radical.
• New Skin
  We think it is allowed to undress these buildings of the Wilhelminian times, to get rid of their décor and to redress them in a modern skin. This skin expresses their inner qualities and their ecological attitude. Public attention is still gained by plasticity - but not through décor but different layers of usable elements. In our opinion it is essential to use outside insulation for energy-efficient renovations of 19th century houses. Additionally we think it is extremely important to find an alternative (insulation-material and surface) for insulation made of Polystrol. The solution must be financially adequate and demountable. Within this report we introduce an alternative.
• Using the Roof
  We plead for an intensive use of attics and flat roofs within the city. Depending on the use of the building these roofs should be used privately as well as jointly. The main part of the area should be planted intensively and extensively (partly also to improve the micro-climate).
• Gentle renovation of the basement
  A gentle renovation's main objectives are insulation of the heated areas of the buildings and the reconstruction of the basement without cutting the rising brickwork and without injecting chemicals. You want to accomplish a durable and stable condition without future damage. In most cases this aim is reachable, but it needs detailed analysis and simulations. The software HMS can show the complex connections of the numerous influences of moisture in the basement for the first time. By detailed evaluation of the existing situation and the simulation it will be possible to have detailed guidelines for easy and soft renovations of basements. The influences of the high insulation which is being attached when renovating the whole building must being calculated to guarantee that there will be no future damages.
• Exterior space
  Dedicated exterior spaces for each dwelling unit have been developed, as well to the street as to the garden facade of the house. The considerations have been widely general in order to be adaptable to most of the 19th century buildings. Facing the garden there will be an extension of equal dimension as the building itself. The compactness of the building will thus increase, on the other hand the new façade can thereby take all kinds of loggias, oriel bays, balconies, plantings, solar active tools and thus gain a quality it lacked before.
• INFRAbox
  One of the main issues of the project was to develop a method of implementing all the new infrastructure without damaging the building structure. To meet this goal, a so called INFRAbox has been developed. It is prefabricated and contains all infrastructure: kitchen, bath, WC, heating wall, ventilation, electrical and television/radio and IT installation.

Development of types for senior living in old houses
In the report we give a compendium of solutions which can be transformed and used for many so called "bassena" houses of the 19th century. It can be demonstrated, that "passivhaus" technology is especially appropriate to ameliorate so called "aisle apartments", which own only little façade surface. It will be shown as well, how an apartment facing the aisle will profit from the special situation.

Building services
In this part of the report the application of passivhaus technology on the special building is investigated. Although the building will be able to meet passivhaus criteria after the renovation, no mere air heating system is used as should be in "passiv houses". The reason therefore is, that the apartments are fairly unequal in terms of thermal heat demand and heating load. Furthermore, aged people have increased demands upon room temperature. Last not least a possible demolition of the adjacent buildings must also be considered. All these increased demands can not be matched economically advantageous by the thermal shell only as would be the demand with a mere air heating system.

Calculation of the thermal bridges
For those parts of the building relevant to thermal renovation solutions to minimize thermal bridges have been developed and calculated. The report now provides a first catalogue of thermal bridges considering "Passivhaus" technology and the special construction of 19th century buildings with their very thick walls. These calculations can be used directly on other 19th century buildings or as general clues.

Passivhausprojektierungspaket PHPP 2004
The complete PHPP 2004 has been calculated for the project. The demand of thermal heat is 14 kWh/m²a, the average heating load is 10,7 W/m², primary energy demand for heating, warm water, auxiliary electricity and household electricity is 61 kWh/m²a, primary energy demand without household electricity is 32 kWh/m²a. With the photovoltaic panels the primary energy demand can be reduced by 7 kWh/m²a. We can read from these figures that the demand for household electricity on a primary side is about 50% of the total demand. Excess temperature frequency in summer will be only 5,2% of total time, in spite of an amply amount of glazing and day lighting. Due to high thermal storage mass and the shading of the loggias by PV panels and the auxiliary constructing for the plants thermal conditions in summer will be excellent.

Contact

pos architekten ZT KEG
Arch. Dipl. Ing. Ursula Schneider
Maria Treu Gasse 3
1080 Wien
Tel: 01/4095265, Fax: DW 99
E-Mail: office@pos-architekten.at