Cost-effectiveness of increasing airtightness of houses.

Air infiltration through the exterior envelope of a residential building impacts significantly on the heating energy consumption and cost, especially in a cold climate such as Montreal's. Therefore to renovate existing houses to the level of new well-built houses in terms of airtightness will lead to a reduction of the heating energy costs. By considering the life-cycle energy consumption and the initial cost of renovation, and the CO2 tax credits, the paper estimates the cost-effectiveness of this type of renovation.

The impact of airtightness on system design.

States that 80% or more of infiltration is due to the many imperfections designed into the building envelopes. Discusses the problem and the role of ANSI/ASHRAE Standard 62-1999.

House-dust mite allergen concentrations (Der f 1) and mould spores in apartment bedrooms before and after installation of insulated windows and central heating systems.

Attempts to determine the influence of the installation of highly insulated windows and central heating systems on indoor climate, and mite-allergen (Der f 1) and mould spore concentrations. A before and after study was carried out on 98 apartment bedrooms, with measurements taken of air exchange rate, temperature and humidity. A lifestyle and housing conditions questionnaire was undertaken by the occupants and dust on carpets and mattresses was analysed for mould spores and Der f 1.

Air toxics in a new Australian dwelling over an 8-month period.

Outlines a 'healthy house' design for suburban Australia. The design incorporated a tight building envelope and a ducted mechanical ventilation (and heat recovery) system, providing a minimum ventilation rate of 0.35 air changes per hour. Partial filtration and dehumidification of the air was also included. Low-VOC building materials were chosen. Total volatile organic compound (TVOC) concentrations were approximately 4,000 microgrammes per m3 just after construction, decreasing by a double-exponential model to 300 microgrammes per m3 by eight months, which is good.

Creating airtight and healthy homes.

States that with the ill effects of poor indoor air quality often in the news these days, it pays to design and build a house that is healthy from the start. States that a comprehensive approach to residential design has emerged in recent years that makes both energy conservation and good indoor air quality achievable in homes.

Why and how is airtightness stimulated in the proposed new energy performance regulation for the Flemish Region.

The airtightness performances of buildings and ventilation systems can have a major impact on the indoor climate (IAQ, thermal comfort,...) and on the energy performance. Measurement results for Belgian buildings clearly show that the airtightness is often moderate to very poor. As part of the proposed energy performance legislation for the Flemish Region, it is envisaged to pay attention to the airtightness of buildings and ductwork. In the first part of the paper, results found for Belgian buildings and systems are briefly presented and discussed.

Building airtightnesses in the new French thermal regulation RT 2000.

Ventilation plays an important role in the RT 2000 regulation. The ventilation system is of course taken into account, but also the building envelope airtigthness on which this paper focuses.

Airtightness in the framework of the Dutch Energy Performance Regulation.

The NEN 5128 "Energy performance of dwellings and residential buildings- Determination method" [1] describes a procedure to calculate the energy performance coefficient EPC. The requirements are given in the Dutch Building Decree [2]. The energy performance is expressed as an Energy Performance Characteristic (EPC). In this EPC procedure ventilation and air tightness play an important role. This paper describes the role of ventilation and air tightness in the Energy Performance Standard. Moreover it gives the alternative way of the so called equivalence principle.

Airtightness and ventilation of a naturally ventilated house in Finland.

This paper illustrates the airtightness and ventilation performance of a recently built ecological house in Helsinki, Finland. The wood frame house, which is built with no plastic vapour retarder, has a satisfactory air tightness (3 ach at 50 Pa). The ventilation measurements show that the outdoor ventilation rate provided by the natural ventilation system tended to be lacking (i.e., less than the required value of 0.5 ach) even though the measured CO2 concentrations were generally satisfactory (i.e., below 1000 ppm) when the bedroom doors were open.

Shattering the energy barrier.

Describes how methods used in widespread energy efficient residential buildings in Germany are now being applied to larger buildings. Germany's Passiv Haus Institut has become a leading centre in developing a specification for the next generation of energy efficient buildings - the Passive House Standard. In 400 residential building the standard has reduced total energy consumption to 12% of the UK norm. Describes how this approach has been applied to a 2,200 m2 office and factory in Colbe, Marburg. The three-storey structure was completed in autumn 1998.