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Diffuse ceiling ventilation is an innovative ventilation concept where the suspended ceiling serves as an air diffuser to supply fresh air into the room. Due to the large opening area, air is delivered to the room with very low velocity and no fixed direction, therefore the name ‘diffuse’. Compared with conventional ventilation systems (mixing or displacement ventilation), diffuse ceiling ventilation can significantly reduce or even eliminate draught risk in the occupied zone. Moreover, this ventilation system presents a promising opportunity for energy saving, because of the low pressure loss, extended free-cooling period and night cooling potential. The investment cost of this ventilation system is about 5-10% lower than the conventional ones, because the acoustic ceiling could be directly applied as air diffuser and the use of plenum to distribute air reduces the cost of ductwork. There is a growing interest in applying diffuse ceiling ventilation in offices and other commercial buildings because of the benefits from both thermal comfort and energy efficiency aspects.The design guide introduces the principle and key characteristics of room air distribution with diffuse ceiling ventilation and the design procedure, which focus on the application of wood wool cement panel.

This report is prepared as a user guide for everyone who will submit their resources to PROF/TRAC material repository.PROF/TRAC team welcomes any expansion of the repository with the new projects and resources within Nearly Zero Energy Building (nZEB) construction.

Diffuse ceiling ventilation is an innovative ventilation concept where the suspended ceiling serves as an air diffuser to supply fresh air into the room. Due to the large opening area, air is delivered to the room with very low velocity and no fixed direction, therefore the name ‘diffuse’. Compared with conventional ventilation systems (mixing or displacement ventilation), diffuse ceiling ventilation can significantly reduce or even eliminate draught risk in the occupied zone. Moreover, this ventilation system presents a promising opportunity for energy saving, because of the low pressure loss, extended free-cooling period and night cooling potential. The investment cost of this ventilation system is about 5-10% lower than the conventional ones, because the acoustic ceiling could be directly applied as air diffuser and the use of plenum to distribute air reduces the cost of ductwork. There is a growing interest in applying diffuse ceiling ventilation in offices and other commercial buildings because of the benefits from both thermal comfort and energy efficiency aspects. Although the interest in the diffuse ceiling ventilation is growing recently, the practical experiences are quite limited and the knowledge is not well structured with this system. These become the motivations in developing the design guide. This design guide aims to establish a systematic understanding of diffuse ceiling ventilation and provide assistance in designing of such a system. The guide is targeted at design engineers, architects and manufacturers and the users of diffuse ceiling technology.The design guide introduces the principle and key characteristics of room air distribution with diffuse ceiling ventilation. It provides an overview of potential benefit and limitations of this technology. The benefits include high thermal comfort, high cooling capacity, energy saving, low investment cost and low noise level; while the limitations include condensation risk and the limit on the room geometry. Furthermore, the crucial design parameters are summarized and their effects on the system performance are discussed. In addition to the stand-alone ventilation system, the integrations of diffuse ceiling ventilation with other HVAC systems are also discussed. Especially, the coupling with the thermally activated building system (TABS) is addressed and the control strategies for optimal operation is proposed. Finally, two case studies demonstrated the application and the deign procedure of the ventilation concept are presented.

The IEA Annex 64 focusing on low-ex communities aims at the improvement of energy conversion chains on a community scale, using exergy analysis as the primary evaluation mode. Within this Annex the participants discuss important aspects and available methods for energy and exergy assessment as well as the added value of aiming for low exergy (LowEx) communities. The reason to exploit the exergy approach is that it provides critical insight into how the maximum potential of energy resources can be used, resulting in a reduced need for high quality energy sources. This insight cannot be obtained with energy analysis. However, other aspects play a role when designing an optimal energy system, such as costs or CO2 emissions. There can be reasons that justify exergy destruction. To address these issues the working definition for the annex is that “a LowEx community is a community for which the energy system is designed in such a way that exergy destruction is minimized, or that all exergy destruction is justified by other reasons (e.g. economic / social, other sustainability reasons)”. This paper gives more background on the definition and presents a general overview of exergy analysis of energy systems in the built environment. Different approaches and opinions are discussed, including how these affect the results. The aim is to create a common ground for consideration low exergy systems at the community scale by setting clear precedents for defining evaluation methods, system boundaries, and input classification.

Buildings in Europe are the largest end use sector and especially residential buildings account for two thirds of this energy use. Despite the fact that building characteristics play a major role in a dwelling’s energy consumption, occupant characteristics and behaviour significantly affect this energy use as well. The Ecommon campaign monitored 32 residential dwellings for 6 months in the Netherlands, capturing quantitative (temperature, CO2, humidity, movement, boiler and ventilation electricity consumption, real time and total electricity and gas consumption on the meter) and quantitative data (comfort perception, actions taken like closing and opening windows, thermostat use, use and type of clothes, and metabolic activity). Additionally in the beginning of the campaign a survey was given to the tenants with questions on income, gender, education level, thermostat and ventilation preferences, bathing patterns and other related data. This paper describes the experimental set up of the campaign, the temperature and occupancy profiles for each type of room for the 32 dwellings and the findings on the clothing patterns and metabolic activity. Temperature profiles show that these dwellings have higher temperatures through the whole day than the common assumption of the daily average of 18 o C suggested for the calculations of the national simulation software. A method is demonstrated on how a combination of motion detection and CO2 can lead to reliable occupancy profiles.

This report aims to present the details and the validation tests of a single family house building energy model. The building model includes furniture / additional indoor content, phase change materials, ground source heat pump and water-based under floor heating system.

La ventilazione naturale, meccanica o ibrida è un meccanismo ben noto ed utilizzato da tempo per il controllo della qualità dell'aria indoor. Tuttavia, in tempi recenti, sotto la spinta dei requisiti sempre più stringenti posti dalla normativa Europea in relazione all'efficienza energetica degli edifici, si è iniziato a rivolgere un crescente interesse verso la ventilazione, specie naturale, quale strumento per il raffrescamento passivo degli edifici. Le recenti evoluzioni del quadro normativo e legislativo, infatti, hanno portato nel cor-so del tempo a costruire edifici sempre più isolati termicamente e sempre più a tenuta d'aria. Tali misure hanno consentito indubbiamente di ridurre la domanda energetica per il riscaldamento invernale, ma hanno determinato delle crescenti problematiche di surriscaldamento dell'ambiente interno. Molti degli edifici ad alta efficienza energeti-ca di nuova costruzione presentano la necessità di essere raffrescati non solo nel periodo estivo e/o primaverile, ma anche in alcuni momenti della stagione invernale. Uno dei rimedi per ovviare a questo inconveniente, in modo energeticamente efficien-te, è quello di utilizzare la ventilazione. Quando la portata d'aria di ventilazione è ge-nerata primariamente per il controllo dei carichi termici di raffrescamento si parla di "Ventilative cooling" o "Raffrescamento per ventilazione". L'effetto benefico di questo provvedimento è duplice. Da un lato agisce sul bilancio termico dell'edificio, sfruttando la portata d'aria per rimuovere i carichi ambiente e, dall'altro, incrementa lo scambio termico sul corpo umano, poiché aumenta la velocità locale dell'aria sulla pelle, modificando quindi e le sensazioni termiche. Permette, inoltre, di abbinare la funzione di controllo dell'IAQ con quella del controllo termico. Una corretta progettazione ed utilizzo di questa tecnica deve tuttavia considerare con attenzione una serie di elementi critici e di potenziali inconvenienti. In primis, l'efficacia del ventilative cooling è legata ad una progettazione attenta dell'involucro edilizio e del sistema edificio/impianto. La misura è infatti efficace solo in quei casi dove gli apporti solari ed endogeni siano stati opportunamente e preventivamente ri-dotti. Secondariamente, l'utilizzo di aria esterna non termodinamicamente modificata può determinare problematiche di umidità relativa interne. Infine, specie nel caso di ventilazione naturale, l'impossibilità di filtrare l'aria immessa e la necessità di realizzare portate volumetriche significative comporta rischi connessi al deterioramento del-la qualità dell'aria indoor e la nascita di situazioni di rischio per ciò che concerne il discomfort locale da correnti d'aria. Nel presente articolo verranno illustrati i principi fisico tecnici alla base del ventilative cooling, si fornirà una panoramica delle strategie mediante cui questa tecnica può essere implementata negli edifici e si analizzeranno criticamente vantaggi e svantaggi. Infine, saranno presentati alcuni esempi realizzativi

BIM Building Information Model or Modelling connects many different informationsystems from various actors during the building construction process with eachother in one easily accessible and understandable model. BIM assures an effectiveand efficient building construction process by reducing failing cost and reduces theuse of materials by so called clash-controls. More and more buildings andinfrastructural works are completed with help of BIM and materials, energy, timeand money are saved by doing so. But why not use BIM for the exploitation phase ofboth new and existing buildings? By connecting the BIM model with the otherexploitation information systems as Facility Management Information Systems(FMIS), and Building Information Systems it’s possible to create an easilyaccessible and understandable building and operating information managementtool. Furthermore using BIM during the exploitation will increase the BIM market.This paper makes clear that BIM an make a big difference in the quality of theexploitation and operation of buildings, by helping creating a better andcomfortable indoor climate while reducing energy losses and costs. FacilityManagers should be the owners of this “exploitation and operation BIM” and have to know which information they must extract from the BIM and how to manage this information system. Another benefit will be time savings, and thereby money savings, because searching, reconstruction and updating building information again and again is not needed anymore. The paper also discuss some of the problems with the implementation and use of such a BIM.

The existing housing stock plays a major role in the realization of the energy efficiency targets. The non-profit housing sector in the Netherlands dominates the housing market as it represents 31% of the total housing stock. In the municipality of Amsterdam, where this share is even 46%, subsidies were given to housing associations between 2011 and 2014 when an energy renovation of their rental property took place and resulted in a better energy performance. The aim of this paper is to examine the impact of thermal renovation on the actual and the predicted energy consumption of the dwellings concerned and to compare both types of consumption. For the non-profit rental dwellings that have undergone renovation in Amsterdam, we use longitudinal data from 2009 to 2013 to examine their actual and predicted gas consumption before and after renovation. The main outcome of the analysis is that in almost all groups of dwellings the gas consumed after renovation decreased significantly. Most of the dwellings had a combination of measures performed and the actual gas consumption savings depend on these combinations. Despite the fact that gas savings after renovation were observed in all dwellings no pattern was found indicating that the better the predicted energy performance achieved, themore actual savings were realized after renovation, but this may be due to the relatively small size of the sample.

This report introduces available educational and training material from the recent IEE projects adapted in the PROF/TRAC repository. An explanation to the categorisation principle of the material in the repository is the key part of this report. The categorisation schema for educational material in the repository is developed using the skills and qualifications structure, developed in WP 2 of PROF/TRAC project. In this way the continuity of the work is well established and the achievements from between the work packages are harmonised.

Ventilative cooling for buildings may lead to cooling energy savings and improvements in thermal comfort, especially in seasonally temperate and warm climates. But, codes and regulations need to better quantify its benefits.

The Hague University in Delft uses an advanced climate control system. All sensors and actuators are monitored and deviations from the sensor data are reported daily. The building manager will have to combine the information from the sensor data in order to draw the right conclusions. In this paper, two possible solutions are described for analyzing the data by a computer program. The first solution is by means of a rule-based program, in which predetermined situations have been defined. The data from the sensors are fed into the program and the program checks whether it matches any of the situations. The second solution is to make use of a Bayesian Belief Network. This is a mathematical model that describes the symptoms and causes of a particular problem. With imported sensor data a computer program calculates the likelihood of particular causes of data symptoms.

Large deviations observed between the actual and theoretical gas consumption in Dutch dwellings, cast a shadow of doubt on the accuracy of the energy labeling method. In this sense, the accuracy of the calculation methods as well as the inputs being fed, fall under the question. According to several studies, the significance of wall’s thermal resistance as one of the most sensitive inputs has become clear. From the lack of sufficient information regarding the exact construction of the existing walls, arises a necessity for in-situ measurements. However, such measurements are generally not being performed because the existing methods demand very long monitoring periods. In this research, a rapid transient in-situ thermal resistance measurement technique, Excitation Pulse Method (EPM), has been introduced, experimentally applied to a case study, and compared to the existing international standard method ISO 9869, showing a very good agreement. EPM is based on the theory of thermal response factors. It allows in-situ determination of the walls’ thermal resistance and the average volumetric heating capacity in a couple of hours. The method is therefore believed to aid in better and much quicker estimation of the

This study aims at using the InVentilate unit in the cooling case, without heat recovery. It results in a relatively low inlet air temperature. Different solutions have been tested to decrease the risk of draught in the occupied zone:‐ Using a mixer (2 designs)‐ Using an inlet grille‐ Using an inlet cover

This summary presents the main results when MicroVent is used in the cooling case, without heat recovery. Experiments have thus been performed with relatively low inlet air temperature (below 15°C). Different solutions have been compared to decrease the risk of draught in the occupied zone:‐ using an inlet grille‐ using an inlet cover‐ using a mixer (2 designs)

From the results, it is clear that the knowledge about possible subsidies and counseling is not great among the respondents. They neither know about the possibilities to seek information and advice, nor do they know about the schemes from which grants are given in relation to energy savings of different kinds. There is however more knowledge about the economic grants than about the counseling, and some groups know more than others. The homeowners who have lived for less than one year in their current house have little knowledge about their opportunities and the longer the respondents have lived in the same house, the lower the amount that have not heard about the possibilities for grants and/or counseling. Furthermore, a tendency is seen in the age distributed groups; the younger the homeowner, the higher the amount that have not heard about the presented offers and the lower the amount that have knowledge about the possibilities in the scheme and counseling. Finally a trend visualized is that the longer the education and the higher the income, the higher the level of knowledge about the schemes, the counseling and the possibilities. At the same time, the respondents with a high income also have a large percentage who have not heard about the offers compared to the other income groups.There have been many reflections about energy saving initiatives and many of the initiatives have already been performed. There is however still a high number missing and particularly the depth of the renovation needs to be increased for Denmark to approach the defined objectives. The positive is that the listed tasks are predominantly carried out or considered to save energy, indicating that the homeowners are aware of this benefit.On the wish list presented to the homeowners, five wishes were selected significantly more than the remaining seven (More daylight, more view to the surroundings, new façade, change the lay-out, improve the comfort, improve the indoor environment, create a garden/terrace). The five are; Lower energy consumption, re-insulation of the house, new windows, new kitchen/bath and finally a new roof. Since these are at the top of the wish list it is expected that, by including these in a potential renovation, the renovation can be found more appealing. Hence the five wishes should be part of a motivation strategy to increase the incentives for energy renovations for the homeowners.The evaluation of the five concepts provided knowledge about the investment limit for private energy renovations and the limit for how much the homeowners think is acceptable to pay for the potential benefits and savings.The general picture is that the prices of the first three concepts (160.000 DKK, 120.000 DKK and 310.000DKK) are fair compared to the outcome, but when the needed investment is at 550.000 DKK and above, the majority think it is too expensive despite the benefits.The investment limit for the private renovations is defined on the basis on the homeowners’ interest in performing similar projects as the presented. The average limit is below 310.000 DKK the price of concept 3. However some of the respondents have a higher limit, and naturally some a lower limit. To increase the amount of deep renovations large private investments are needed and the results show that this is most likely to happen;• Before the homeowners have lived for one year in their house, since the investment limit is lowered as time goes on, and these homeowners have proven willing to pay more than average for the same benefits and savings.• As long as children under the age of 18 years are living in the house, because the homeowners here have a higher than average interest in conducting similar project, hence a higher investment limit.• When the homeowners are young as this is where the interesting investment is largest.• In households with a high yearly income. Both the interest in similar projects and the acceptance of the prices of these show that these homeowners will invest in extensive projects.The respondents’ wishes presented in this report and previously defined motivation factors based on other results from the same questionnaire survey [9,13,14] are therefore expected to generate more motivation in the four above mentioned situations.

The current trend towards nearly-zero energy buildings has led to an increased risk of overheating throughout the year. Use of the cooling potential of outdoor air can be an energy efficient passive solution to this.

Danmarks målsætning er i følge Regeringens klimaplan fra 2013 at være et samfund uafhængig af fossile brændstoffer efter 2050. Det kalder på betydelig energieffektivisering og forøgelse af den vedvarende energiproduktion. Byggeriet udgør, jf Energistyrelsens energistatistik, 35 % af det samlede energiforbrugi Danmark og en forbedring af bygningers energieffektivitet er derfor afgørende. Udvikling af energineutrale bygninger er et vigtigt skridt i denne retning.Denne publikation er en del af det arbejde, der er foretaget i Strategisk Forskningscenter for Energineutralt Byggeri og omhandler den forskning, som er gennemført af forskningscentret vedrørende energitekniske løsninger for energineutralt byggeri.

The objective of this technical report is to provide information on the accuracy of the experiments performed in “the Cube” (part I, II and III). Moreover, this report lists the experimental data, which have been monitored in the test facility (part IV). These data are available online and can be used by other researchers.

The “Comfort Houses” is one the most ambitious building project in passive single-family houses in Denmark until today. Ten houses have been designed and built by different consortiums. Besides fulfilling the German passive house standard the goal was to build the houses within Danish traditions of architecture and construction. The objective of the research presented in this paper is to compare the different design processes behind the making of passive houses in a Danish context. The processes are evaluated as regards to the “Integrated Design Process” and the “Traditional Design Process”. Analysing the data it shows that the majority of the consortiums have worked in an integrated manner, however there are still room for improvement. Additionally, the paper discusses the challenges of implementing the Integrated Design Process in practise and suggests ways of overcoming some of the barriers and thereby providing suggestions for future work with low energy houses. The “Comfort Houses” project is the most ambitious building project for passive, single-family houses even undertaken in Denmark. Thus far, different consortiums have designed and built 10 houses. Besides fulfilling the German passive-house standard, the goal of the project was to build the houses within Danish tradition of architecture and construction. The objective of the research presented in this paper, is to compare the different design processes behind the making of passive houses in a Danish context. We evaluated the process with regard to the integrated and traditional design process. Data analysis showed that the majority of the consortiums worked in an integrated manner; though there was room for improvment. Additionally, the paper discusses the challanges of implementing the integrated design process in practice and suggests ways of overcomming some of the barriers . In doing so, we also provide suggestions for future work with low-energy houses.

The Integrated Renovation Process (IRP) is a user customized methodology based on judiciously selected constructivist and interactive multi-criteria decision making methods (Galiotto, Heiselberg, & Knudstrup, 2014 (expected)). When applied for home renovation, the Integrated Renovation Process for Homes (IRP4homes) supports, informs and reassures homeowners to decide on a sustainable renovation of their home while getting the corresponding associated benefits and therefore a home more adapted to their lifestyles. The IRP4homes also helps the building experts to be more effective for the quantitative analyses and the generation of the renovation scenarios so they get more time for the cost optimisation and the qualitative analysis of the homeowners’ needs, wishes and behaviours.

The experiments are carried out in a climate chamber located at the Department of Civil Engineering Aalborg University. The objective of the experiments is to evaluate the performance of the system combining diffuse ceiling ventilation and thermally activated building construction (TABS) in terms of thermal comfort and energy performance. 20 cases with different boundary conditions are conducted varying on climate condition heat load. TABS water temperature and flow rate with or without diffuse ceiling. The energy evaluation includes energy balance of test room and cooling or heating capacity of TABS. And the thermal comfort is analyzed by draught rate vertical temperature gradient and radiant temperature asymmetry. Finally the effect of plenum and diffuse ceiling is discussed.This report mainly focuses on the experiment results and discussions. Therefore, some details about the measurement are not presented in this report but can be found in the experimental plan made before.

Frequent discussions of double skin façade energy performance have started a dialogue about the methods, models and tools for simulation of double façade systems and reliability of their results. Their reliability will increase with empirical validation of the software. Detailed experimental work was carried out in a full scale test facility ‘The Cube’, in order to compile three sets of high quality experimental data for validation purposes. The data sets are available for preheating mode, external air curtain mode and transparent insulation mode. The objective of this article is to provide the reader with all information about the experimental data and measurements, necessary to complete an independent empirical validation of any simulation tool. The article includes detailed information about the experimental apparatus, experimental principles and experimental full-scale test facility ‘The Cube’. This covers such problem areas as measurements of naturally induced air flow, measurements of air temperature under direct solar radiation exposure, etc. Finally, in order to create a solid foundation for software validation, the uncertainty and limitations in the experimental results are discussed. In part II of this paper the reader will be introduced to the experimental results, and their analysis

Frequent discussions of double skin façade energy performance have started a dialogue about the methods, models and tools for simulation of double façade systems and reliability of their results. Their reliability will increase with empirical validation of the software. Detailed experimental work was carried out in a full scale test facility ‘The Cube’, in order to compile three sets of high quality experimental data for validation purposes. The data sets are available for preheating mode, external air curtain mode and transparent insulation mode. The objective of this article is to provide the reader with all information about the experimental data and measurements, necessary to complete an independent empirical validation of any simulation tool. The article includes detailed information about the experimental apparatus, experimental principles and experimental full-scale test facility ‘The Cube’. This covers such problem areas as measurements of naturally induced air flow, measurements of air temperature under direct solar radiation exposure, etc. Finally, in order to create a solid foundation for software validation, the uncertainty and limitations in the experimental results are discussed. In part II of this paper the reader will be introduced to the experimental results, and their analysis