English

The thermal comfort of the “Home for Life” dwelling in Denmark, the “LichtAktiv Haus” in Germany and “Sunlighthouse” in Austria is investigated with a particular focus on the control strategies and the role of solar shading and natural ventilation (ventilative cooling). These houses are three of six buildings in the Model Home 2020 project (Feifer, 2013). They have generous daylight conditions, and are designed to be energy efficient and CO2 neutral with a good indoor environment.

According to researchers, climate change is inevitable in the 21st century. As far as Greece is concerned, this climate change will be related to an increase in ambient surface temperature and to a decrease in annual precipitation. On the other hand wind patterns will not change significantly. Also, no significant changes are expected for global solar radiation. Regional climate models related to Greece show low uncertainties. The climate of Greece is typical Mediterranean with wet, cool winters and hot, dry summers.

Non-invasive, scalable, building retrofit solutions are very attractive deep renovation techniques to improve energy efficiency in existing buildings; this includes natural ventilation for cooling due to the low impact nature of the installation. However, a number of criteria that are important to natural ventilative cooling strategies can be substantially altered as a result of an external retrofit solution.

The indoor environmental quality and health of occupants in approximately 5000 dwellings were investigated by questionnaire covering the whole of Japan. The purpose of this survey was to clarify the association between indoor air quality and adverse health effects and to study effective ways of keeping indoor air clean using mechanical ventilation. Questionnaires were distributed to 7812 occupants living in mechanically ventilated houses across 47 Prefectures in Japan in February 2012 of which 5265 occupants replied.

Envelope airtightness is incorporated in the French Energy Performance (EP) Regulation (named “RT”) and is a key factor in the reduction of energy consumption. From 2006 until 2012, the French 2005 Energy Performance Regulation (RT, 2005) did not require justification of envelope airtightness. However, constructors could get certification for airtightness through a quality management (QM) approach, in order to build better-than-regulatory buildings.

Carbon dioxide has already been recognized as a potential tracer gas for estimating the mean air exchange rates of a room or building. The wind direction and mean wind velocity have also been identified as critical factors that affect the air infiltration. In this paper, the indoor CO2 concentration has been logged at three specific points in an office room for seven selected measurement-periods. The decay method was used to estimate the infiltration rates (ac/h).

New homes currently being built within the UK all incorporate some type of ventilation system, the majority of which are of the fixed mechanical fan type. These generally come in three generic designs known as single room background ventilators, continuous mechanical systems and continuous mechanical systems with heat recovery. Installation, inspection and commissioning of these systems is covered by Building Regulations, and there are training schemes in place which allow individuals to become Competent Persons to undertake these tasks.

An air curtain generated by a jet is used to enhance an exhaust hood’s capture ability in many research studies on local ventilation systems. This paper focuses on experimental methods to investigate the flow characteristics formed by an exhaust hood associated with a jet. The basic flow characteristics of this kind of exhaust hood are obtained by smoke visualization as a jet forms an air curtain, and the flow field is a combination of three parts: the jet flow region, the exhaust flow region and the vortex flow region.

This paper presents a study of the potential for the use of natural ventilation systems in Portuguese multi-family residential buildings under winter climatic conditions. The behaviour of various natural ventilation systems is tested in a standard residential dwelling, using the TRNSYS 15 and COMIS 3.1 software programs. This study leads to the conclusion that the use of hybrid ventilation systems can save a considerable amount of the energy normally spent on continuously operating mechanical ventilation systems.

Focusing on the turbulence in natural ventilation and its impact on both occupant thermal comfort and building energy consumption, this paper presents a review of existing unsteady natural ventilation envelope flow models, as well as other techniques that have potential application to further our understanding of turbulence in natural ventilation and develop models which capture the dynamics and effects on thermal comfort.