Criteria catalogue for quality assurance in the construction of passive houses built in wood
Modern energy-efficient construction demands high standards both in its planning as well as in its construction. Standards of quality have to be maintained and negative experiences to be avoided in order to lastingly anchor a positive image of the passive house within the population. Up until now systems of quality assurance in use are almost exclusively geared towards building materials or -products and components for building services. However, systems of quality assurance specifically devised for (actual) construction are very rare.
The aim of this project is to formulate a system of quality assurance for passive houses built entirely in wood or built with a mineral-based interior and a wood based exterior. This is comprised of developing a criteria catalogue for detecting possible weak spots and sources of error during timber construction of passive houses. On the other hand a construction site tool for quality assurance during the period of building on the construction site will be formulated.
At the beginning of the research programme an extensive media research within German speaking countries took place, dealing with systems of quality assurance in the areas of timber construction, construction of passive houses and building service. This was supplemented with areas of assessment systems for the general building area. Through this research scattered available knowledge was focused and depicted in a distinct way. A list including short descriptions of systems of quality assurance and of assessment is now available to users as a concise source of information.
As a next step the analysis of the building process was to follow.
For the examination of building processes a suitable project was chosen for each current system of timber construction - timber frame construction, timber massive construction, frame construction, mixed construction (wood - mineral). In choosing the projects it was very important to select storey houses or houses divided into several flats which are typical representatives of their particular way of construction. The analysis of the construction processes shows the complete order of events in the construction of a building. This includes a classification of the several steps involved in the building process of each project. Subsequently, the construction site tool was developed as a check list for timber construction, structurally starting from the upper edge of the foundation.
"Smart housing", a building in Feldstraße, Brunn am Gebirge was chosen as the first project to be analysed as an example for timber frame construction (in its shell).
With the help of this analysis the missing areas for the criteria catalogue were defined and elaborated in close cooperation with expert planners and the executive companies of the analysed project. The collaboration with the expert planners and the executive businesses ensures the usefulness and aptness of the acquired solutions in practice.
Parallel to the analysis of the building processes and the analysis of the details specific to timber construction a criteria catalogue for systemic solutions of building service was developed. This also includes specific solutions in detail: starting from different possible conceptual approaches to integration and function of ventilation and heating in passive houses, the appropriate details of building service for timber construction are depicted respectively in relation to the building process. For this purpose, examples of reference were analysed, already existing details were collected and new details developed as models. The respective checklist / the "construction site tool" for a project-specific, given combination of construction and building service concept was provided through the indications for correct planning and realization of the conceptual solutions and of the building service details.
After the analysis of all projects and after the compilation of the criteria catalogue for timber construction and building service, all solutions were submitted to a final revision within the areas of construction physics and structural planning.
The Criteria catalogue
On the one hand the main focus of the criteria catalogue was put on the construction of house automation facilities suitable for passive houses (electro-, sanitary installation, heating, ventilation) regarding the integration for timber construction and of parameters for construction physics, such as airproof, heat-, fire-, and sound protection. On the other hand, the focus was put on solutions based on different possible potential construction systems (i.e. timber frame construction, timber massive construction, frame construction, mixed construction). Special attention was paid to the collaboration of individual trades and the interfaces resulting from this collaboration.
The construction site tool
The criteria catalogue together with the analysis of the building processes ultimately provided the basis for the compilation of the construction site tool, which enables a practical implementation of the compiled matters.
The construction site tool inherently displays an innovation in the area of quality control during construction and is aimed to become a standard tool for the building of future passive houses in timber construction. With this construction site tool, criteria of objectives are listed according to each step within the construction progress. These objectives need to be achieved by the appropriate trade concerned. The construction site tool also serves as quality objective evidence for the construction of the passive house after its completion. Furthermore, it offers the building owner to maintain a simple, traceable view over the construction quality of the passive house.
The construction site tool as well as the criteria catalogue should be made available to planners, construction businesses and on-site construction managers free of charge in order to ensure high-quality planning and construction of passive houses.
Dipl.-Ing. Heinz Geza Ambrozy
Architect, Zivilingenieur für Hochbau, staatl. befugter u. beeideter Ziviltechniker
Dipl.-Ing. Christoph Muss
team gmi Ingenieurbüro GmbH
Schönbrunnerstraße 44/10, 1050 Wien
Tel.: +43 (1) 545 74 89-0
Fax: +43 (1) 545 74 89-17
Dipl.-Ing. Dr. Wilhelm Luggin
ZT-Büro DI Wilhelm Luggin
Graf Starhemberg-Gasse 43/5, 1040 Wien
Tel.: +43 (1) 504 53 33
Fax: +43 (1) 504 53 37
Dipl.-Ing. Thomas Zelger
IBO - Institut für Baubiologie und -ökologie
Alserbachstraße 5/8, 1090 Wien
Tel.: +43 (1) 319 20 05-16
Fax: +43 (1) 319 20 05-50