Lessons learned from a ten-year monitoring in residential buildings equipped with humidity based demand controlled ventilation in France

Humidity-based DCV systems have been widely used in France for 35 years and are considered as a reference system, including for low-energy residential buildings. Indeed, most of the new residential buildings, which must be low-energy buildings to comply with the RT 2012 energy performance regulation, are equipped with such systems. Feedbacks from two long-term studies show the durability of the humidity sensitive components and show the robustness of this system to bad maintenance or use by occupants.

40 Years of Modeling Airflows

The modelling of air flows to investigate indoor air quality and energy issues has been a topic at the AIVC for all of its 40 years. Models have been developed that range in complexity from single-zone algebraic expressions that can be calculated by hand to complex multi-zone approaches that integrate contaminant transport and other functions.

The Role of Carbon Dioxide in Ventilation and IAQ Evaluation: 40 years of AIVC

The purpose of this summary is to review Air Infiltration and Ventilation Centre activities, as reflected in its publications, related to indoor carbon dioxide over the 40 years that have transpired since its creation. These activities, like most applications of indoor CO2 to the fields of ventilation and indoor air quality, have focused on the following: control of outdoor ventilation rates, i.e., demand control ventilation; use as a tracer gas to measure outdoor air change rates; providing an indicator or metric of IAQ; and, directly impacting human health, comfort and performance.

Performance of a Heat Recovery Ventilation System in the Canadian Arctic

A demonstration house was previously built and commissioned in Iqaluit, Nunavut, Canada. The purpose of the overall effort is to evaluate the performance of a high-performance building located in the Canadian Arctic, while considering the unique social, economic and logistical challenges associated with its remote location. Previous work consisted of monitoring and reporting on the energy consumption due to heating between April 2016 and April 2017.

Long-term performance and resiliency testing of a dual core energy recovery ventilation system for the Arctic

The Arctic environment is challenging for housing ventilation and heating systems. Energy consumption and demand for space heating for northern remote community residential buildings are very high. Airtight built northern homes require energy efficient and effective ventilation systems to maintain acceptable indoor air quality and comfort, and to protect the building envelope from moisture damage.

Influence of Ventilation on Radon Concentration in a Study Case in Spain

Radon gas is a well-known building´s pollutant which can affect negatively people´s health (WHO, 2009). Radon´s source is the soil underneath buildings. Radon moves from the soil to the buildings by advection through cracks and joints, and diffusion through porous materials. Once radon enters buildings it can accumulate in lower areas due to lack of ventilation. Ventilation is one of the main ways to prevent radon from accumulating in enclosed spaces in the case of moderate radon concentrations up to 600 Bq/m3 (Collignan, 2008). 

An argument for a reality check in the ventilation industry: We still have an energy crisis, in practice, and are not generally, in practice, achieving better indoor climate

In 2017 the Danish Building and Property Agency started a project titled “Avoiding energy waste in ventilation systems” by tracking the actual energy use in a sample of their 4 million m2 portfolio of buildings through on-line energy management tools. The project is not complete, but the key preliminary findings  described in this paper are: 

Exist’air: airtightness measurement campaign and ventilation evaluation in 117 pre-2005 French dwellings

Between 2017 and 2018, the Centre for Studies and Expertise on Risks, the Environment, Mobility and Planning (Cerema) organized an airtightness measurement campaign in 117 multi-family collective and single-family French dwellings. These dwellings were built before 2005, that is, before the release in 2005 of the fifth French thermal regulation for new dwellings, that was the first to introduce specific requirements for airtightness.

Developing a new passive tracer gas test for air change rate measurement

Ventilation is critical in interpreting indoor air quality (IAQ), yet few IAQ assessments report ventilation rates; even when they do, the measurement method is often not fully described. Most ventilation assessments use a tracer gas test (TGT) to measure total air change rate. In a TGT, the indoor air is marked with an easily identifiable gas (tracer) so that the air change rate can be inferred by monitoring the tracer’s injection rate and concentration.

Measuring the ventilation rate in occupied buildings and adapting the CO2 tracer gas technique

Measuring ventilation rates in occupied dwellings is challenging but represents the conditions that occupants experience. This paper explores the constraints of existing methods when measuring the ventilation rate of occupied buildings and proposes a new method addressing some of them.