draught

Literature on the in-situ performance evaluation of Mechanical Ventilation with Heat Recovery (MVHR) in low-carbon social housing suggests that they can maintain a healthy ventilation rate in bedrooms in the UK. However, issues with noise and draught have been reported frequently. These issues may affect the sleep quality of occupants and have a detrimental effect on health and wellbeing. This research aims to present a quantification of these issues by carrying out detailed monitoring and evaluation at two case study sites in Wales, UK.

Thermal environment affects occupants’ work performance and well-being. Office workers’ complaints regarding thermal environment are often related to either too warm room temperature or draught. Efficiency demands have increased the heat loads in offices, and increased cooling is needed to control the room air temperature. Draught problems occurs typically in these situations when the workstation is located in the downfall area of the inlet jet. 

Proposals for solutions in accordance with German standard DIN 4108 Teil 7 What does real life look like? What can actually be solved? Challenges, interface issues between the different trades and crafts, and possible suggestions for solutions.

For several years indoor comfort is measured in halls of hospitals by architecture students from the Delft University of Technology. Questionnaires and interviews have shows that patients and visitors have very few complaints about the indoor comfort in hospital halls.  

The mainstream of air-conditioning system for medium and small sized buildings is conditionally air mixing ventilation with ceiling cassette unit of packaged air conditioner (PAC), however, it may bring a high cold-draught risk to occupants, due to the direct drop of the supply air jet. To solve this problem, the air mixing ventilation system can be improved into an air based radiant air-conditioning system by stretching the non-flammable membrane under the ceiling with PAC, thus the cold-draught of PAC could be substantially eliminated and the indoor environment could be improved easily.

Electric fans used for cooling or local ventilation are common household appliances around the world, especially in developing countries. They offer many advantages such as low cost and energy savings, as well as easy implementation. However, the airflow from fans is often considered to be less comfortable than the sensations produced by natural winds. In order to avoid the draught induced by fans, and to investigate dynamic airflow characteristics of household fans, an anemometer was utilized to measure the corresponding time series of the air velocity.

In hot climates a comfortable indoor environment is important. Mechanical fans are often introduced to cool the indoor air. However, it has been found that the airflow from such fans is not comfortable, especially compared with natural wind. Artificial airflow in an enclosure has been known to disturb hair, irritate eyes, and distract occupants. This paper presents the result of an experimental study on the characteristics of household airflow inducing appliances. The details of experiments carried out in the laboratory are described.

This work deals with experimental investigations on human reaction to local air movements of people in global thermal comfort, performing light activity. An analysis on draught risk was developed comparing the results with previous research findings on human response to draught. The intensity of air velocity, in terms of mean value and relative turbulence, was referred to the level at which normally clothed people could perceive and feel air movements behind the neck, in global neutral thermal condition.

Wall-mounted air conditioning systems including window-type and split-type air conditioners are widely used in Asian countries. However, these systems blow cold air directly into the working space perpendicular to the mounted wall and may make people affected by these air conditioners experience discomforts such as draught and uneven temperature distribution. Now a wall-mounted air conditioning system is expected to effectively implement the displacement ventilation system for space cooling and cold draught avoiding.

Approved Document (AD Part F1) of the Building Regulations [1] for England and Wales identifies trickle ventilators as an option for providing natural background ventilation in commercial buildings. This paper reports the results of a field measurement study carried out at BRE during the winter of 1994/95 to assess the effectiveness of trickle ventilators. Two occupied office rooms were equipped with trickle ventilators and measurements were carried out for a fortnight period in each office, with the ventilators closed during the first week followed by a week with them open.