Submitted by Maria.Kapsalaki on Wed, 04/17/2019 - 16:01
This paper presents results from a project on the assessment of the indoor air quality (IAQ) benefits that might accrue from the use of a balanced energy recovery ventilation system. The study compared the whole-building pressure, IAQ and ventilation performance of a balanced energy recovery ventilation (ERV) system with that of an exhaust-only ventilation system (continuous exhaust from master bathroom).
Submitted by Maria.Kapsalaki on Wed, 04/17/2019 - 16:00
This article proposes to study the impact of envelope and internal partition walls airleakage distributions, on the indoor air quality (IAQ) performance. It is based on a preliminary performance-based approach using formaldehyde with three emission levels (low, medium, high). This multizone modelling (CONTAM) approach uses as performance indicators, the average concentration per room as well as the percentage of time of exceeding the limit value (ELV) of 9 µg.m-3.
Submitted by Maria.Kapsalaki on Wed, 04/17/2019 - 15:59
The implementation of decentralised ventilation units is growing, especially in the residential retrofit. These systems are typically simple to install on site (usually in the external façade with no additional ductwork) and allow room-by-room control strategies. Until now, decentralised systems are evaluated by applying the same methodologies as for centralised ventilation systems, even though different boundary conditions apply. Some differences are for example:
Submitted by Maria.Kapsalaki on Wed, 04/17/2019 - 15:56
Diffuse ceiling ventilation is a novel air distribution concept, where the space above a suspended ceiling is used as a plenum and fresh air is supplied into the occupied zone through perforations in the suspended ceiling panels. Due to the low momentum supply, the airflow in the room is driven by buoyancy force generated by heat sources. The previous studies indicate that the diffuse ceiling ventilation system can effectively eliminate the draught risk in the occupied zone and provide a comfortable indoor environment even with low-temperature supply.
Submitted by Maria.Kapsalaki on Wed, 04/17/2019 - 15:54
Air infiltration contributes to a heat loss typically representing up to one third of the heating demand of a building. The building airtightness, also quantified as air leakage, is the fundamental building property that impacts infiltration. The steady (de)pressurization method (blower door) is the widely accepted standard process for measuring building air leakage. However, this method requires the enclosure to be pressurised to a typical range of 10-60 Pa, which is not physically representative of the pressures experienced by buildings under natural conditions.
Submitted by Maria.Kapsalaki on Wed, 04/17/2019 - 15:53
The air renovation of a building should be controlled in order to ensure a proper level of indoor air quality while minimize heat losses. It is a crucial point for the future energy efficiency goals. However, air infiltration rate in buildings is a complex parameter which is influenced by several boundary conditions. Although a detailed dynamic analysis could be used to properly characterize the phenomenon, estimated values can be obtained from experimental methods, as Blower Door test and gas concentration-based approaches.
Submitted by Maria.Kapsalaki on Wed, 04/17/2019 - 15:47
In this paper a new methodology is presented to determine airtightness of buildings. The common method for airtightness testing is through fan pressurization with a blower door test. The new methodology also uses fan pressurization. Instead of an external fan, it uses the building fan system to pressurize the building.
Submitted by Maria.Kapsalaki on Wed, 04/17/2019 - 15:46
Nowadays the improvement of building airtightness is an essential condition to achieve high energy performance of buildings. Therefore, there is a need to precisely describe and quantify buildings infiltrations.
Submitted by Maria.Kapsalaki on Wed, 04/17/2019 - 15:45
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 exchange rate can be inferred by monitoring the tracer’s injection rate and concentration.
Submitted by Maria.Kapsalaki on Wed, 04/17/2019 - 15:44
In France, the control of ventilation system at commissioning is mandatory in the context of the Effinergie + label and the measurement of airflows in residential houses is mandatory since 2017 in this label. The Promevent project (2013-2016) was aiming at improving the reliability of those controls. Guidelines have been issued for visual inspection of system, airflow measurements at air terminal devices (ATD) and ductwork airtightness measurements.