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indoor climate

Measured moisture buffering and latent heat capacities in CLT test houses

This research investigates the significance of the moisture buffering and latent heat capacities in exposed cross-laminated timber (CLT) walls with the respect to indoor climate and energy consumption. Hygroscopic materials have the ability to accumulate and release moisture due to change in the surrounding humidity. The moisture buffer capacity is regarded as this ability to moderate, or buffer, the indoor humidity variations. Latent heat refers to the heat of sorption due to the phase change from vapour to bound water in the material and the other way around.

Air heating of passive house office buildings in cold climates – how high supply temperature is acceptable?

The impact of over-tempered air on the perceived indoor climate was evaluated by questionnaires filled in by the users of the first office building with passive house standard in Norway. In this building, the heating demand is covered entirely by warm air supplied into the rooms through the ventilation system.

Comparison of two ventilation control strategies in the first Norwegian school with passive house standard

The Marienlyst School is the first educational building in Norway built according to the passive house standard. This building benefits from a super-insulated and airtight envelope. While this reduces the heating demand largely, it also enhances the risk for poor indoor air quality and overheating compared to conventional buildings. It is therefore particularly important to implement an efficient ventilation strategy in order to avoid adverse effects on the health, well-being and productivity of the pupils.

Use of DCV for heating and the influence on IAQ in passive house buildings

Measurements were performed in a test room at SINTEF building and infrastructure, Oslo. The test room is 16 m2 and built according to NS-EN 442-2.  Measurements of various air flow rates (9 l/s, 18 l/s, 34 l/s and 50 l/s) and different supply air temperatures (2, 4, 6 and 10 degrees over room temperature) were performed. Tracer gas (SF6) measurements were performed to evaluate ventilation effectiveness and age of air in occupied zone.

Summer Thermal Comfort in New and Old Apartment Buildings

In Nordic countries overheating and cooling systems have not been the issue in apartment buildings. Historically and even in the beginning of 2000 there were not indicated such problems. New architecture with larger windows and strict energy performance requirements has changed the situation. If adequate measures are not used, new buildings may be easily overheated.

Lessons learned from the EPBD concerted action

The EPBD (EU Energy Performance of Buildings Directive) Concerted Action is a cooperative effort from all 27 EU Member States (MS), plus Norway and Croatia, together with the European Commission. It is running since 2004, under the Intelligent Energy programme since 2007. It aims at providing support to MS in their effort to transpose and then implement the EPBD, identifying the best solutions and practices that MS can then adopt and thus move towards harmonization throughout the EU.

A Newly Designed Supply Diffuser for Industrial Premises

The results of this investigation revealed the airflow distribution from a new design of supply diffuser under non-isothermal conditions. To illustrate the indoor climate parameters in the occupied zone, for both the heating and cooling seasons, an experimental investigation was carried out in industrial premises. The indoor climate was explored at ankle, waist and neck levels for a standing person at different positions, to determine the variation of the thermal comfort indexes and draught rating (DR) with position in the facility.


In order to clarify determine the energy consumption and the indoor environment of an experimentalhouse with energy efficient design, measurements were taken since January 2006. The house isoccupied twice a year, for a week each in summer and winter. Simulation was used to predict theenergy consumption and indoor environment of the experimental house with a typical four-personfamily. The aim of this study is to understand the influence of energy efficient building design on energyconsumption and indoor environment.


Field measurements of the indoor climate have been carried out in 128 lightweight timber-framedetached houses in Finland and in Estonia during the years 2002-2005. The temperature and relativehumidity were continuously measured in bedrooms, living rooms and outdoors for each house at 1-hourintervals over a 1-year period.

Indoor Hygrothermal Loads in Estonian Dwellings

This paper analyzes the indoor hygrothermal loads measured in 27 detached houses and in 13apartments. A survey was conducted during the years 2003-2006 in Estonia. The temperature andrelative humidity (RH) were continuously measured in bedrooms, living rooms, and outdoors at onehour intervals. For the hygrothermal analysis, the determined design curve of the moisture excess forhouses with low occupancy on the higher 10 % critical level was +4 g/m3 during the cold period(Tout ? +5 C) and +1.5 g/m3 during the warm period (Tout ? +15 C).