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The results of Annex 35 are summarized in two final reports and specific results of individual subtasks and workgroups are reported in technical reports and papers.

State-of-the-art Report

The first results of the project is a review of hybrid ventilation technologies, which covers the followings topics:

Introduction with expectations of Hybrid Ventilation in the participating countries

HV offers significant opportunities for improving the indoor environment and reducing energy demand. Naturally, because of climate variations and other factors, different countries have differing expectations of HV.

Survey of existing buildings with hybrid ventilation systems

The survey of 22 existing buildings shows solutions to specific problems. It is clear that a successful hybrid ventilation design depends on an integrated approach, in which optimal use is made of sustainable technologies.

Barriers to, or opportunities for, hybrid ventilation in building codes and standards

The survey describes the paragraphs in building regulations, standards or recommendations that may have an impact, positive or negative, on hybrid ventilation in relation to IAQ, thermal comfort, energy performance, acoustics, and fire and safety.

Control strategies for hybrid ventilation

The complexity of a control strategy depends on the system's functional purpose. In the provision good IAQ advanced control strategies are important to balance energy and IAQ considerations. It is possible that simpler strategies may provide adequate summer temperature control.

Analysis tools for hybrid ventilation

There are very few, if any, tools available that have been specifically developed for analysing hybrid systems. In fact, the existing building survey revealed that only a few buildings used any kind of design tool developed for hybrid ventilation systems.

Principles of Hybrid Ventilation

The booklet "Principles of Hybrid Ventilation" is the final product of the project. It is aimed at newcomers giving an introduction to hybrid ventilation and the research results of Annex 35. 

More detailed technical reports are also available, see Publications: Technical reports.

Proceedings og Hybvent Forum 01

The second International one-day Forum on Hybrid Ventilation was held at Delft University of Technology May 14, 2001. It was organized by Prof. ir. J. J. M. Cauberg, Departmemt of Building Engineering, Delft University of Technology and Ing. Ad van der Aa, Cauberg-Huygen, The Netherlands.

Download The proceedings (3.78 MB)

Technical reports

Research papers

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