modelling

Project RESILIENCE set out to examine overheating in a variety of building archetypes, but also examined several aspects of overheating related to the tools that are used, the weather data that has been employed in dynamic simulations and potential low-cost solutions to improving the resilience of the existing non-residential building stock that relies upon ventilative cooling.

Project RESILIENCE set out to examine overheating risk in a variety of non-residential building archetypes, but also examined several aspects of both overheating risk metrics and indoor thermal resilience evaluation criteria. Assessing the future risk of overheating in new and retrofitted buildings is usually undertaken by applying national regulations and buildings codes where minimum criteria is typically published.

The global increase in building cooling demands poses a challenge for designers striving for net zero energy consumption. The prevalent use of mechanical cooling underscores the necessity for designers to consider Ventilative Cooling as a viable alternative in the early stages of building design. Recent research findings suggest that the pre-design stage has the same influence for promoting Ventilative Cooling strategies as the schematic and detailed design stages for practitioners, yet limited impactful decision making occurs at this stage.

Smartness is all around us. The HVAC industry is developing more and more products that have sensors, are intelligent, are connected to the Internet and are being controlled via apps. According to a recent European survey among installers, the request and demand from clients for installing home automation and smart products is the highest for HVAC installations. 

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.

As policy makers strive to reduce the energy demands of houses by reducing infiltration rates, an unintended consequence could be a fall in the quality of indoor air with corresponding negative health effects at a population scale. Measuring pollutant concentrations in-situ is difficult, expensive, invasive, and time consuming and so the simulation of indoor conditions, using representative models of a housing stock, is a more common method of investigation.

Natural and Hybrid ventilation systems, by using exclusively or partially natural driving forces, help to reconcile building energy sobriety and good Indoor Air Quality (IAQ). However, in France, Building Regulations restrict the use of natural ventilation by imposing minimum airflows in buildings. Natural ventilation, whose driving forces are atmospheric conditions, has an efficiency depending on the climatic region.

There are three common methods used to analyse Indoor Air Quality in buildings: in-site measurements, laboratory measurements, or the simulation of indoor spaces using a validated computational model. Each have their advantages, but computational models are generally used to predict air quality in a wide range of indoor environments because they are quick, cheap, and non-invasive. A wide range of inputs are required to accurately simulate airflow and pollutant transport. However, this information may not exist or may only exist in abstract forms.

According to the International Energy Agency, buildings represent over one-third of total final energy consumption. Thus, a more sustainable future begins with low energy buildings which must combine comfort and function using passive systems and new evolving technologies. Policies to reduce building energy consumption and carbon emissions have been developed worldwide during the last decades.

Mastering building airtightness is essential to meet the requirements of current and future building codes, not only for saving energy but also for ensuring moisture safety. Perfect airtightness is difficult to achieve: failures are often observed, due to bad design or poor workmanship. Some published investigations proved that leaking air mostly flows through porous material and thin air channels, due to material imperfections and construction tolerances.