The airtightness of a building envelope impacts upon the magnitude of uncontrolled air leakage and associated ventilation energy losses. A building's airtightness can be assessed using a steady state fan pressurisation technique. This paper describes a study on the largest building in the UK ever to have had its airtightness tested. Power law regression analysis revealed a good correlation between flow rate into the building and observed pressure differentials.
For historical and demographical reasons, in many European countries, an important part of educational building must be retrofitted. These retrofitting must be carried out in a context of reduction of greenhouse emissions and energy consumption.Among different targets for retrofitting, there are the improvement of indoor environment. In fact, educational buildings are particularly vulnerable to indoor environment problems. Studies have indicated a correlation between the way educational buildings are designed, or retrofitted, and student performance.
To better quantify the impact of different window opening models in comparison to ventilation techniques a multizone ventilation model, incorporating the CO2-production of the inhabitants, was developed, using Comis-Transys. The reference model represents a free-standing dwelling in which infiltration is the only source of fresh air. Through a series of simulations natural ventilation systems (standard, user controlled or CO2-based demandcontrolled), air-tightness techniques and/or window opening models (deterministic or stochastic) are added.
This paper presents the results of a field study conducted on 8 houses (out of a set of 31) owned and managed by a French social housing public leasing company. The central objective of our investigation was to evaluate and characterize the envelope leakage of these houses in order to propose and prioritize rehabilitation scenarios. For this, envelope leakage measurements were performed together with infrared thermography measurements.
In France, most of the public project managers have collective dwellings built in the 70’s 80’s with first generation mechanical ventilation systems. These systems are not well perceived by the occupants who find them noisy, uncomfortable in winter and w
Single- and double-section manufactured homes were instrumented in 2001-2003 to measure continuous energy usage and air infiltration with respect to the environmental conditions of a windy cold dry climate. The test site near Arlington, Wyoming, USA is ideal for testing the energy (and structural) performance of manufactured housing due to the naturally occurring high winds (in excess of 35 m/s annually) and temperature extremes (+35 to -35C). Tests included tracer gas monitoring, pressurized leakage tests, and infrared (IR) video scans.
In moderate climates, adventitious ventilation helps in keeping the water vapor balance in a building under control. This does not hold in hot and humid climates, where the outside air is a moisture source. Adventitious ventilation should be avoided in such climates and intended ventilation flows must be dried before entering the space. Anyhow, could adventitious ventilation also generate moisture problems in moderate climates? To get an answer, a reference case was analyzed with the air leakage distributed over facades and roof.
In France, ventilation in new residential buildings must be designed and dimensioned according to the Health regulation (Arrêté du 24 mars 1982) which is basically based on required extract air flow rates. Two points are to be noticed : 1) The extract flo
In order to facilitate nationwide analysis of ventilation and indoor air quality issues in residential buildings, a set of homes has been defined to represent the housing stock of the United States. This so-called 'suite of homes' is based on two residential housing surveys, the U.S. Department of Energy Residential Energy Consumptions Survey (RECS) and the U.S. Census Bureau American Housing Survey (AHS). The RECS dataset includes about 6000 U.S. residences and the AHS covers about 60000, and are both intended to periodically characterize the U.S. housing stock.
The study reviewed each Code/Standard with respect to requirements relating to acommon set of ventilation factors and criteria. The main factors include the following:1. Protection against Depressurization - given the increase in more tightly built homes,how do the differing C/S protect against combustion gas spillage into the dwelling.2. Ventilation Capacity - what are the requirements for total mechanical air changerates, and high and low airflow capacities?3. Contaminant Removal - what exhaust requirements are there for specific rooms inthe dwelling?4.