In practice, the commonly used Dutch design criterion for long-term thermal comfort in buildings-the weighted temperature exceeding hours method--often leads to confusion.The criterion is hard to understand for non-experts, and many doubt the validity of the present criterion : how sure are we that meeting the requirements really means that future occupants will be comfortable?

This paper summarises the adaptive approach to thermal comfort and analyses the data collected inSCATs surveys of thermal comfort throughout Europe. These results are used to suggest acceptable bands of temperature in heated or cooled and in free-running buildings. The results suggest that comfort temperatures in real buildings cannot be accurately predicted because of multiple differences between individuals, buildings and cultures in different countries.

An energy performance regulation has to consider not only energy, but -either explicitly or implicitly- also the relevant comfort aspects: indoor air quality (IAQ), lighting level, humidity level, temperatures (summer, winter) and hot tap water availability.
After all, the easiest way to minimize energy consumption is to switch off heating, ventilation, lighting, hot tap water, ...
What is the relation with the EPBD requirements on energy performance? Is there a potential conflict? Is there a need for additional minimum comfort requirements?

There is increasing evidence that indoor environmental conditions substantially influence health and performance. Macro-economic estimates show that the potential benefits from indoor environmental improvements for the society are high. Some calculations show that the estimated cost of poor indoor environment is higher than energy costs of heating and ventilation of the same buildings.

This paper gives an overview of a few quality assessment methods used for ventilation systems. They cover two categories of approaches: regulatory compliance checks, that are external to the building project actors; voluntary contract-based quality assessment procedures, e.g., embedded in a certification scheme. The examples are briefly described and analysed. Quantitative results are given where possible.

The European Energy Performance in Building Directive (EPBD) requires methods for the calculation of the energy performance for use in the context of building regulations.The European Commission has supplied a Mandate (M343,2004) to CEN to develop a series of standards, each covering a part of the calculation of the energy performance of buildings and procedures for the inspection of heating and airco systems.The paper introduces briefly the methods for the calculation of the energy needs for heating and cooling of buildings and the relation with the higher level standards.

Forced air distribution systems can have a significant impact on the energy consumed in residences. It is common practice in U.S. residential buildings to place such duct systems outside the conditioned space. This results in the loss of energy by leakage and conduction to the surroundings. In order to estimate the magnitudes of these losses, 24 houses in the Sacramento, California, area were tested before and after duct retrofitting. The systems in these houses included conventional air conditioning, gas furnaces, electric furnaces and heat pumps.

The ventilation of an attic is critical in estimating heating and cooling loads for buildings because the air temperature in the attic is highly sensitive to ventilation rate. In addition, attic ventilation is an important parameter for determining moisture accumulation in attic spaces that can lead to structural damage and reduced insulation effectiveness. Historically, attic venting has been a common method for controlling attic temperature and moisture, but there have been no calculation techniques available to determine attic ventilation rates.

Field tests were carried out in two flat ceiling, residential attics at a dedicated test site over a two year period. The scope of this paper is to present measurements of ventilation rates, indoor-attic exchange rates, temperatures and wood moisture contents at various locations in the attics. Attic ventilation rates are correlated with wind speed, wind direction, and attic-outdoor temperature difference. Wind speed is shown to be the dominant driving force for ventilation; however, wind direction is important particularly when the attic is sheltered.

The wind shadow model has been developed to calculate the wind sheltering effects of upwind obstacles for air infiltration calculations. This effect must be determined for infiltration calculations because, in almost all situations, only the unobstructed mean wind speed is known for a building site. This model has adapted the theoretical calculation procedures developed for far wake centreline velocity deficit calculations to near field flows, where shelter has a significant effect.