PR2012

The Proceedings of the 33rd AIVC Conference " Optimising Ventilative Cooling and Airtightness for [Nearly] Zero-Energy Buildings, IAQ and Comfort", held in Copenhagen, Denmark, 11-12 October 2012.

The Presentations at the 33rd AIVC Conference " Optimising Ventilative Cooling and Airtightness for [Nearly] Zero-Energy Buildings, IAQ and Comfort", held in Copenhagen, Denmark, 11-12 October 2012.

The importance of adventitious air leakage under normal operational conditions and its reduction in order to save energy is highlighted by the relvant building standards of many countries. This operational leakage is often inferred via the measurement of air permeability, a physical property of a building that indicates the resistance of its fabric to airflow. A building’s permeability is the measure of airflow rate through its envelope at a constant pressure differential of 50 Pascals.

It still remains heat loss and high risk of moisture condensation occurrence at glass of window because they have relatively poor insulating qualities and usually contribute the greatest heat loss by heat conduction in residential buildings. Although many attractive window systems are proposed to reduce heat loss such as double and triple glazing, low emissivity film coated glazing, argon gas injected glazing, vacuum insulated glazing, double-pane and triple-pane window etc., it has also demerits such as high initial cost and indoor air quality problem.

An efficient thermal insulation of glazing or window frame is important because poor insulating performance usually cause the largest heat loss on any buildings. As one of the methods decreasing heat loss of buildings, we proposed a dynamic insulation system applied to window frame, and its energy saving performance and applicability for buliding had been confirmed using numerical simulation in previous study [1].

Accuracy in estimation of airflow through windows is the key parameter for modelling and designing of naturally ventilated buildings. The flow through windows is usually described by the orifice flow plate equation. This equation involves the discharge coefficient. In practice, often a constant value of discharge coefficient is used. The constant value of discharge coefficient leads to deceptive airflow estimation in the cases of centre-pivot roof windows. The object of this paper is to study and evaluate the discharge coefficient of the centre pivot roof window.

The purpose of this study is to evaluate the effects of measuring position of air-tightness performance in Flat-type and Tower-type apartments. Air-tightness performance was measured on entrance doors using the Blower Door System in accordance with CAN/CGSB 149 and on the windows using air-tightness Measuring (KNS-serise) in accordance with JIS A 2201. The air-tightness test was performed with newly builted apartments in 2011. The air-tightness test results on location were converted into ACH50 for comparison.

The paper in hand investigates the potentials and limitations of ventilative cooling strategies in the moderate Central Europe climate region of Vienna, Austria, offering a a basic load break down of the thermodynamic night ventilation sub-processes plus an overview over frewuent practical limtations and finally a recent monitoring result from a single family model home.

The global requirement to dramatically reduce greenhouse gas emissions places an increased emphasis on reducing energy demand associated with dwellings. Where improved energy efficiency is in part achieved by tighter control of ventilation, there is potential for both positive and negative impacts on health from reduced air exchange in the indoor environment. Although increased air tightness may help improve indoor temperatures and reduce the ingress of pollutants from the external environment, it may increase concentrations of those from indoor sources.

The work evaluates the applicability of façade-integrated ventilation systems in a Nordic climate. For this purpose the state of the art of façade-integrated ventilation (FIV) and demands for ventilation system in Norway and criteria for an comprehensive evaluation are identified. In this framework agreements between national requirements and system-specific performance are assessed. The evaluation investigates indoor environment and comfort with focus on aspects of indoor air quality.