airtightness

The paper describes the development of unsteady pulse pressurisation techniques for measuring the leakage of buildings. The original version of the technique (the UP technique) has been investigated experimentally and theoretically in a single cell test space. The initial results are very promising, with a good degree of repeatability and similar sensitivity to changes in leakage levels as the conventional steady (DC) technique. An interesting outcome of these early tests was the observation that quasi-steady flow could be established in a short time.

Twenty terrace houses without heating system has been built in Sweden. The houses are extremely well insulated and very airtight. They are also quipped with a high efficiency ventilation heat recovery system. The total electricity consumption and the air temperature in two positions has been monitored for each of the houses on an hourly bases. Further has the environmental conditions, i.e. outdoor temperature, wind, sun etc been monitored. In six of the houses separate measurements of electricity consumption for ventilation and hot water has also been performed.

Describes a new airtightness test procedure for testing a single zone within a multizone building. The technique enables the measurement of partition leakage so that it can be subtracted from the overall zone leakage.

Describes how substantial differences resulted from performing a 'Duct Blaster' test during the framing stage and at completion. Outlines the tests used to pinpoint the problem. The tests included: frame-stage leakage - unit untaped; frame-stage leakage - unit taped; finish-stage leakage - face taped; finish-stage leakage - complete-taped; subtraction method; leakage to outside. The data obtained allowed the quantification of leakage at air handler units, at metal supply boots to outside and at supply registers to inside.

Most dwellings in the United States are ventilated primarily through leaks in the building shell (i.e., infiltration) rather than by whole-house mechanical ventilation systems. Consequently, quantification of envelope air-tightness is critical to determining how much energy is being lost through infiltration and how much infiltration is contributing toward ventilation requirements. Envelope air tightness and air leakage can be determined from fan pressurization measurements with a Blower Door. Tens of thousands of unique fan pressurization measurements have been made of U.S.

The government is set to crack down on leaky buildings in 2001. So what's likely to happen and what should the construction industry be doing?

This work presents a field measurement study, investigating the airtightness of 64 French dwellings less than ten year old. Buildings have been classified according to the type of construction (masonry or timber frame) and of occupancy mode (multi- or single- family). Using a fan-depressurization technique, we assessed the air leakage rate of each dwelling, based on a theoretical flow model that relates the infiltration airflow rate to the differential pressure .

mechanical ventilation is needed to avoid indoor air quality problems. Many new conventional houses have low natural air change rates ...... and are tight enough to require mechanical ventilation, but most have none.