AIVCPR

This project deals with reviewing EBC's Annex 5: "Air Infiltration and Ventilation Centre" activities & contributions on the occasion of the project's 40^th year of operation. 

The objective of this project is to disseminate information on the activities & key work delivered in the framework of the AIVC over the last 40 years.

Approach:

The trend to increasingly complex ventilation controls (particularly for residences) is leading to many new possibilities related to IAQ and energy optimization. This project is needed to ensure that ventilation systems claiming to be “smart” meet appropriate performance requirements and to provide technical information for system designers, ventilation codes and standards and researchers. 

The objectives of this project are to:

• Review technical information to develop consensus for standardization purposes

Internationally there are many different requirements and regulations for ventilation.  Sometimes the variation is more than a factor of five. There are strong drivers to reduce energy consumption for HVAC, and therefore the spread in requirements and regulation is worthwhile to study. To reduce ventilation flows there is a necessity to understand the reasons behind. Demand control to reduce this flows is in many countries growing but the control parameters are quite different, for instance humidity versus CO2 control.

There have been many new sensors introduced on the market claiming that they can perform accurate measurements of Indoor Air Quality. Many of them are low-cost sensors that can be applied at the mass scale. The subsequent question is what is and should be considered to be the metric of Indoor Air Quality. No consesus on this matter has yet been achieved. Few metrics have been proposed in the past including most known CO2 and TVOC concentrations but actually only CO2 concentration has been widely used in the applications related to built environment and HVAC.

Building airtightness tests have become very common in several countries, either to comply with minimum requirements of regulations or programmes, or to justify input values in calculation methods. This raises increasing concerns for the reliability of those tests.

There are four key sources of uncertainty in airtightness testing:

The European market for residential ventilation is highly driven by energy performance regulations. In new buildings the share of balanced ventilation with heat recovery is increasing as a result of more severe energy performance requirements (NZEB). The energy labeling for residential ventilation units and the ecodesign requirements for ventilation units may be drivers for a more wide-spread application of heat recovery ventilation in new buildings.

The trend towards more nearly zero energy buildings and much more airtight buildings represents specific challenges for cooker hoods in residential buildings. 

There is a trend to perform more ventilation and air infiltration measurements in buildings, either to strengthen commissioning procedures or to learn from field data. This trend is stronger in nearly zero-energy buildings projects or programmes given the significant share of ventilation and infiltration losses on total building energy use.

An increasing number of countries (e.g. Czech Republic, Denmark, France, Germany, Ireland, Netherlands, Norway, Portugal, UK) include in their regulations either required or recommended minimum airtightness levels with or without mandatory testing. The number of tests performed on a voluntary basis is rapidly increasing either because of the energy penalty for untested buildings in the calculation method or due to the specific requirements of a given program. Furthermore, mandatory testing came gradually into force in the United Kingdom, Portugal, Denmark and France.

There exist several initiatives in different parts of the world to bring a stronger basis to ventilation requirements in relation to indoor air quality and health issues, for example, at LBNL in the US (Healthy efficient homes program), within the HealthVent project in Europe (2010-2012), at Health and Wellbeing project in Japan, Development of healthy and clean residential building standard in Korea (2008-2012) or within the French Observatory for Indoor Air Quality (running since 2001).