Better airtightness: better or worse ventilation?

In Finland there are not yet any regulations or standards concerning the airtightness of buildings. Drafts have caused discussion about whether controlled airtightness would increase the building costs too much, and improved airtightness worsen the indoor air quality. In modern Finnish buildings a good or satisfactory airtightness can be achieved with normal careful workmanship. To secure good indoor air quality, a functioning ventilation system is also necessary. There seems to be no return to traditional 'breathing' structures and natural ventilation.

Air leakage or controlled ventilation?

This paper compares the conventional exhaust system with a supply-exhaust system with regard to the possible degree of control of the air exchange in the individual rooms. Ventilation efficiency and air exchange efficiency are defined and some examples show the local concentration, mean ventilation efficiency and mean air exchange efficiency for some simple ventilation schemes. Exhaust systems require a very tight building with small make up air openings. The ability of the different systems to avoid leakage out from the building of indoor air is also compared.

Residential ventilation systems. Boligventilationssystemer. Teori og erfaringer.

A survey of literature on the theory and practice of residential ventilation. The three main topics are ventilation needs, air movement in buildings, and the properties of ventilation systems. The ventilation need under winter conditions is estimated at 0.35 l/s m2 or, for a dwelling with kitchen and bath, 35 l/s. In fact, ventilation requirements are not constant but it is difficult to find a formula covering the various considerations.

Minimum ventilation rate. A research report.

An investigation of the minimum fresh air supply per person required to prevent the occurrence of unacceptably offensive odour due to stale air in offices and similar buildings. The study was made under everyday conditions as far as possible, in different buildings, various size rooms, different densities of occupancy, with men or men and women, and with mechanical or natural ventilation.

BTPI - a building thermal performance index.

In this paper, an empirical method is proposed which qualifies the thermal performance of buildings through the entire year. The thermal quality parameter (BTPI) is intended to be an instrument for the implementation of new energy regulations for buildings, especially for those that are located in areas with mild climate and no heating or air conditioning systems. Portuguese climatic zones are typified for summer and winter and predominance factors for seasonal loads are defined.

The prediction of air infiltration through building components. The assembly of a device to measure air infiltration through components with a suggested method of producing data which could be used to form the basis of aprediction model.

Reviews air infiltration measurement methods, prediction models, and flow through components of buildings. Attempts to construct a device capable of measuring air flow through a building component under a given pressure difference and to investigate the existence of a coefficient which, when multiplied by the pressure difference, raised to an exponent, will yield the air flow through that component. Components were tested under differing pressure differences and the testing device was calibrated by a tracer gas technique.

Infiltration, energy conservation and indoor air quality.

One option of reducing residential energy consumption is to improve air tightness but adequate ventilation must be provided for health reasons. Sources of infiltration and factors affecting infiltration rates are described, with methods for quantifying and comparing rates. The relationship with air quality is explained and the effect that air quality has on respiration and health. Typical indoor pollutants are carbon monoxide, carbon dioxide, nitrogen oxides, radon and radon progeny, formaldehyde gas, particulates, tobacco smoke and odours.

Multivariate model for predicting NO2 levels in residences based upon sources and source use

Diffusion-type passive monitors were placed for a two-week period in each of 303 residences in the New Haven (Conn.) area during a 12 week sampling period January to April 1983. For each home NO2 levels were recorded outdoors, and in three ro

Characterization of indoor air quality and "sick buildings"

Notes the increased attention being paid to "sick buildings" of the irritating type. Occupants complain of deteriorated indoor air and subtle medical symptoms that may be related to the indoor air. The problem seems to coincide with energy economising. To evaluate the actual quality of the air in a building it is necessary to conduct field studies with mobile investigation units, taking representative air samples for immediate sensory and chemical analysis.

Predicting thermal comfort of people in naturally ventilated buildings

Describes a new procedure for predicting the thermal comfort of people in naturally ventilated buildings. The procedure starts by obtaining, for each important wind direction, velocity ratios between points of interest inside the proposed bu

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