Blower Doors are used to measure the air tightness and air leakage of building envelopes. As existing 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, quantification of airtightness data is critical in order to answer the following kinds of questions: What is the Construction Quality of the Building Envelope? Where are the Air Leakage Pathways? How Tight is the Building? How Much Ventilation Does the Air Leakage Supply?

The paper summarises an approach to determining the equations governing the air flow through simple cracks subject to fluctuating pressures. To this end, an experimental arrangement has been developed that enables the laboratory simulation of fluctuating driving pressure signals. A standard straight crack was subjected to this signal, which fluctuates in both magnitude and frequency. An air control system permits a high level of fluctuating pressure control.

In order to demonstrate conformity with the current Building Regulations, many house builders are incorporating sumps beneath the ground floor construction of houses within the designated Radon Affected Areas. These sumps will allow for later depressurisation of the below ground floor construction and thereby prevent radon passage to the internal building environment. There are concerns regarding the costs of these measures and also the potential for these sumps to be used by vermin as nesting sites as well as their effectiveness.

Mechanical ventilation of the underfloor space is one of the most effective ways of reducing radon levels in buildings with suspended timber floors. There is a question however whether this ventilation should be supply or extract, sometimes extract is more effective, soinetiines supply is inore effective. This report presents a simple analysis of the problem and suggests the hypothesis that the relative effectiveness of supply or extract ventilation to the underfloor space depends on the relative airtightness of the floor and the soil or oversite surface.

The aim of this study was to unravel the occupational exposure to radon among underground workers. The possibility for radon mitigation by improving ventilation or by sealing was also investigated. 65 workrooms in 19 workplaces has been investigated in the ground floor, in basements and in underground spaces in southern Finland and in middle Finland. Radon concentration varied from 15 to 1636 Bq/m³du ring working hours resulting in annual dose of 0.09 to 10.3 mSv.

In certain parts of the United Kingdom where radon gas seeps from the ground into the basement of domestic housing, normal methods of removing this gas by using under floor extract ventilation is not appropriate. In this situation the radon gas enters the basement through the side walls of the cellar and hence into the house. Using mechanical ventilation to either pressurise or de-pressurise the cellar may be an appropriate solution to this problem, however before installing such a system in a house a ventilation strategy must be established.

The paper presents some selected results of evaluation of improvement effectiveness of thermal insulation and tightness of multifamily dwelling houses located in the region of Silesia. The effect of the modernization work on heat consumption (to heat the buildings) and ventilation performance is discussed. Attention is paid mainly to the sensations of the flat users connected with air flows and change. Prospects of effective implementation of thermorenovation of buildings are evaluated in the conclusions when taking into account predominating role of ventilation.

In recent years plants have increasingly become an integral part of building interior design. Greened office space and large enclosures can provide a better human environment not only because of psychological reasons. Due to photosynthesis, plants interact with the "aerial" environment. Water evaporation aflects room air humidity and temperature. Water uptake rates offive common plants in typical indoor climate conditions have been studied. Water evaporation of these plants can now be predicted in architectural design studies.

A kitchen is one of the major moisture producing areas in a dwelling. In order to prevent condensation and mould growth the relative humidity should not be too high. This paper describes a set of experiments comparing methods of kitchen ventilation and their effectiveness at moisture removal. The three methods of extract ventilation were: 1. A mechanical extract fan of extract rate 60 l/s 2. A passive stack ventilation system 3.

Multifamily buildings with natural ventilation are still being built and exploited. Such buildings are often equipped with individual gas-fired water heaters located in windowless bathrooms. It implicates the possibilities of improper gas exhaust as a result of the decrease of infiltration, what could be sometimes even harmful for the occupants' health. Based on the numerical simulations, analysis of ventilating air flows in typicalmultifamily dwelling house will be carried out.