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Green design is now a ubiquitous term in the profession of architecture, yet the energy performance of buildings in real-world conditions is poorly documented. A large number of buildings use substantially more energy than is predicted during design, and one possible explanation is that designers do not adequately understand the impact of thermal bridging through insulation on the energy use of a building. This study proposes a methodology that uses the parametric design program Grasshopper to quantitatively analyze infrared images for the degree of thermal bridging in a wall assembly. The end result is a user-friendly tool that architects can use to study the relative energy performance of their buildings in the field, giving them an increased understanding of the energy efficiency of their designs. Case studies of various details show a ten to fifty-five percent reduction in the effective R-value of the overall wall assemblies due to thermal bridging. / 10000-01-01

Inom dagens byggande i Sverige ställs allt högre krav på den värmeisolerande förmågan hos klimatskärmen i de hus som byggs. Detta ställer i sin tur högre krav på konstruktionerna och medför även ny problematik. Standardlösningar som tidigare fungerat bra byts ut mot nya, ibland obeprövade, lösningar. De hårdare kraven på energi- och fuktdimensionering innebär alltså att vikten av val av stommaterial ökar vid en projektering. Vi har här försökt ge en realistisk bild av hur valet av reglar kan påverka energi och fukttillståndet hos en byggnad med utfackningsväggar, med fokus på reglar i fält. Till undersökningen användes referensobjekt i form av ritningar som tillhandahölls av handledaren på Clarus arkitekter. Med hjälp av dessa gjordes tredimensionella energiberäkningar som visade dels att valet av material kan ha mycket stor betydelse både för energiförluster och fukttillstånd, samt att sambanden inte nödvändigtvis behöver vara enkla. Valet av reglar har mycket varierande betydelse beroende på hur väggen är uppbyggd. Genom en laboration undersöktes skillnaden mellan slitsade och oslitsade ytterväggsreglar för att ge ökad förståelse och verifiera noggrannheten av beräkningarna jämfört med en verklig vägg. Det sista visade sig svårt att uppnå, men det var tydligt att slitsarna hade mycket stor betydelse för temperaturfördelningen i en vägg. / Construction of Swedish buildings today places higher demands on the heat-insulating capacity of the building envelope in the house built. This in turn places higher demands on the structures and also creates new problems. Standard solutions that previously worked well are being replaced by new, sometimes untested, solutions. The tougher demands on energy and moisture design means that the choice of substrate material is of greater importance than before when designing buildings.Here we have tried to give a realistic view of how the choice of studs can affect energy and humidity conditions of a building with curtain walls, focusing on studs in the field. The survey used reference objects projects in the form of drawings provided by the supervisor at Clarus Architects. Using these, three-dimensional calculations were made showing firstly that the choice of material can be of great importance both for the energy and moisture, and secondly, that the relationship is not necessarily simple. The importance of the choice of studs varies depending on how the wall is built. By a laboratory experiment, the correlation between slotted and unslotted outer wall studs was examined to provide greater understanding and verifying the accuracy of the calculations compared to a real wall. The last task proved difficult to achieve, but it was clear that the studs had great significance for the temperature distribution in a wall.

Med hjälp av Boverkets byggregler och de ISO-standarder som föreskrivs fastställs värmeeffektbehovet för Kyrkbackskolan, Ljusnarsbergs kommunala skola. Ur effektbehovet har sedan ett teoretiskt värmesystem dimensionerats. Resultaten visar att de olika byggnaderna som skolan består av har olika behov beroende på deras utformning. Över trehundra radiatorer och över trehundrafyrtio kilowatt värmeeffekt behövs för att värma skolan enligt de utförda beräkningarna för transmissionsförluster, ventilationsförluster och köldbryggor. Den största osäkerheten finns i köldbryggorna då dessa är baserade på tabellvärden. En rumslista visar vad varje rum i hela skolan har för effektbehov och kan användas vid både installation och injustering. / Using ”Boverkets byggregler” and the ISO-standards that are stipulated in it are the heating requirements determined for “Kyrkbackskolan”, the only school in the municipality of Ljusnarsberg. A theoretical heating system has been designed based on the calculations. The results show that the three different buildings that make up the school have different requirements depending on their layout. Over three hundred radiators and over three hundred forty kilowatts of heating power are required to heat the school according to the calculations of transmission losses, ventilation losses and thermal bridges. The largest insecurity is in the thermal bridges since they are determined using tables. A list shows all the rooms and their heating requirements which can be used when installing or tuning the heating system.

In this thesis project a concrete sandwich wall element of 250 mm insulation of Kooltherm has been resulted to have U-values and ψ-values closer to the passive housing recommendations. However, by using 180 mm thick insulation, no significant difference in the annual energy consumption is observed. Using a metal sheet in the window connection and small concrete brackets, low thermal bridge values are achieved. Low thermal bridge coefficient values were also observed with thick insulation in the foundation and the roof structure, although, it is impossible to achieve values below 0,01 W/mK in the corner connections. Airtightness of the building envelope is more important than the thickness of the wall in the energy consumption simulations. Therefore, the thermal bridging and the U-values of the wall are, in most cases, dependent on the thickness of the element. No conclusions on the structural reliability of the solutions can be extracted from this thesis project. In order to conclude the statements above, this thesis project has been focused on the evaluation and design of a concrete sandwich wall panel. The design of the wall element, including its reinforcement and connectors, while achieving values according to passive housing regulations, is the initial goal of this project. Subsequently, connections between the building components and the wall element are analyzed and designed through several simulations according to the passive housing regulations respectively. Simulation tests took place in Sweco Structures AB offices with the valuable contribution of experts. An existing building project was used and evaluated in order to present the simulation results in a more realistic manner. Several insulation materials have been tested for the thermal and moisture reliability. Using the existing building as a base for information, energy simulations generated the energy consumption results in order to compare different wall thicknesses, and thermal bridging effects. This project is inspired by the needs of building sustainability and efficiency, which has become a significant part of the worldwide effort on reducing the energy consumption on the planet. Regulations regarding building technology have been completely changed and adjusted in the passive housing design. Particular effort has been put on the commercial and multi-residential buildings, in which the energy consumption is usually higher than in small family houses. Concrete sandwich wall panels have been introduced in the building market as an alternative and more efficient way of constructing. Prefabrication has been proved to be less time consuming, although issues on the thermal behavior appear in this kind of structure. The evaluation of the thermal efficiency of the concrete sandwich wall elements has been a significant issue in the civil engineering society and research.

Idag står mänskligheten inför stora förändringar i klimatet, men en ansträngning från alla kan dessa förändringar motverkas. Detta examensarbete är en påpekning som kan leda till en bättre miljö.   Syftet med examensarbetet är att i samverkan med företaget Lönn Energi undersöka och analysera kända köldbryggor i två småhus. Som ligger i närheten av Gävle och jämföra köldbryggsandelen i husen med schablon-påslaget om 20%.  Det som ska beräknas är andelen linjära köldbryggor i förhållande till värmegenomgångskoefficienten, Som resultat visar arbetet att för de två husen som undersöktes att andelen köldbryggor i förhållande till Um går på 4,5% för huset i Årsunda och 8,4% för huset i Lingbo. / Today, humanity is facing major climate changes, but with the efforts of all, these changes can be prevented. This thesis work is a remark that can lead to a better environment.  The purpose of the thesis is to investigate and analyze known thermal bridges in two single-family houses which is located near Gävle. And to compare the thermal bridges percentage in the houses with the recom-mended addition of 20 % in collaboration with Lönn Energi.   As a result, the work shows that for the two houses examined the propor-tion of thermal bridges in relation to heat transfer coefficient Um is 4.5% for the house in Årsunda and 8.4% for the house in Lingbo.

Syfte: Studiens syfte är att belysa utmaningarna som uppstår när byggnader blir alltmer välisolerade för att uppfylla ställda energikrav blir köldbryggornas andel av värmeförlusterna allt större. Köldbryggorna består oftast av svårisolerade anslutningar mellan olika byggnadsdelar och studien undersöker hur det hanteras under projekteringsskedet. Därutöver studeras hur köldbryggornas inverkan för det termiska klimatet förmedlas vidare till en VVS-konstruktör som räknar värmebehovet för att täcka alla förluster som sker genom klimatskalet. Metod: Insamling av data är baserat på att kunskapsinhämtningen görs utifrån den nuvarande kunskapen kring köldbryggor där teorin samt det som i folkmun brukar kallas ”verkligheten” i symbios studerats. För att göra detta har empirin baserats på tre insamlingsmetoder där litteraturen samt dokumentanalys om regler och krav kring arbetsgången för köldbryggor har studerats. Intervjuer i sin tur har varit den metod som tillämpats för att få insyn i hur det går till i ”verkligheten” när man beräknar köldbryggorna.  Resultat: Byggnadskonstruktörer beräknar inte köldbryggor. VVS-konstruktörerna tar liten eller ingen hänsyn till köldbryggorna i värmebehovsberäkningen. Detta innebär att vi har en ansenlig andel värmeförluster som saknas i värmebehovsberäkningar då flera studier påvisar att köldbryggornas inverkan kan spela så stor roll som 20 – 70 % av värmeförlusterna (om de underskattas enligt Building Envelope Thermal Bridging Guide från 2019). Konsekvenser: Då byggnadskonstruktörer inte beräknar köldbryggorna och VVS-konstruktören inte alltid tar hänsyn till köldbryggornas inverkan vid beräkning av värmebehovet så har vi utmaningar som behöver hanteras för att uppfylla förväntade energikrav från beställare och kravställare i form av regler. Följande rekommenderas för att få en förändring i processerna som berör köldbryggorna: ·         Att i regelförsamlingen ”Boverkets byggregler” påtalar vilka psi (Ψk)– och chi (Χ j) -värden som ska eftersträvas likt de enskilda byggnadsdelarnas U-värden (BFS 2020:4, BBR 29). Köldbryggorna ska även verifieras av tredje part. Begränsningar: I studien har inte energikonsulternas roll med att beräkna köldbryggorna undersökt vilket vore ett sätt att öka omfånget och perspektivet på fokusområdet. Nyckelord: Energiprestanda, Hållbarhet, Köldbryggor, Värmebehov. / Purpose: The purpose of the study is to illustrate the challenges that arise when buildings become increasingly well-insulated, to meet the energy requirements, and the share of thermal bridges on heat losses becomes ever greater. Underestimation of the impact of thermal bridges can create problems when e.g., energy goals and operating economy are not met, and it affects the user in the form of poor thermal comfort. The thermal bridges usually consist of connections difficult-to-insulate between different building parts and here the study will investigate how it is handled during the design phase and how the thermal bridges' impact is passed on to an HVAC designer who in turn calculates the number of heats demands to cover all losses through the climate shell. Method: Data collection is based on the acquisition of knowledge based on the current knowledge about cold bridges where the theory and what is usually popularly called "reality" in symbiosis have been studied. To do this, the empirical data has been based on three collection methods where the literature in the form of rules and requirements regarding the workflow for thermal bridges has been studied. Document analyses to study the workflow according to standards are evaluated. Interviews, in turn, have been the method used to gain insight into how things go in "reality" when calculating the thermal bridges. Findings: Building designers do not calculate the thermal bridges at all, and the HVAC designers take little or no account of the impact of thermal bridges in the heat demand calculation. This means that we have a significant proportion of heat losses that are missing in heat demand calculations as several studies show that the impact of thermal bridges can play such a large role in 20-70 % of heat losses if they are underestimated according to the building envelope thermal bridging guide from 2019. Implications: As building designers do not calculate the cold bridges and the HVAC designer does not always consider the impact of the cold bridges when calculating the heat demand, we have challenges that need to be addressed to meet expected energy requirements for customers and requirements. The following are some of recommended for getting a change in the processes that affect the thermal bridges: §  That the National Board of Housing, Building and Planning's building regulations state which psi (Ψk) and chi values are to be sought, like the U-values of individual building components (BFS 2020: 4, BBR 29), and that they should be verified by a third party. Limitations: The limitations that exist are that the study has focused only on building designers and HVAC designers and the role of energy consultants with thermal bridges would be a way to increase the scope and perspective in the focus area. Keywords: Heat demands, Sustainability Energy performance, Thermal bridges.

Det konstrueras i stor utsträckning bristfälliga detaljlösningar på byggnader i dagsläget. Den bärande stommen i konstruktionen prioriteras ofta medan det inte ägnas lika mycket fokus åt att tillgodose de byggnadsfysiska aspekterna. Anledningen till de bristfälliga detaljerna är även att den som utför arbetet saknar rätt kunskap och tid. För att skapa en förbättring behövs ett hjälpmedel! Kunskap och erfarenhet om hur bra detaljer skapas finns redan i företag, svårigheten är dock att sprida kunskapen till de som är i behov av den. Målet med denna rapport är att skapa en metodik som blir startskottet för ett omfattande arbete kring framtagandet av ett detaljbibliotek, vars syfte är att sprida byggnadsfysiska kunskaper inom företaget och inspirera konstruktörer till att konstruera bra detaljlösningar. Biblioteket ska innehålla byggnadsfysiskt utredda detaljlösningar som analyserats enligt den utarbetade metodiken. Metodiken kommer göra det möjligt att på ett enkelt sätt utvärdera detaljlösningar, för att sedan presentera dessa med uträknade värden och rekommendationer i detaljbiblioteket. Via intervjuer med konstruktörer och en omfattande genomgång av byggnadsprojekt, har 7st detaljlösningar valts ut för att utredas och sedan exemplifiera hur dokumenten i detaljbiblioteket kommer att gestalta sig. Exemplen går att se i rapporten, och de kommer även att utgöra embryot till det slutgiltiga detaljbiblioteket. Detaljbiblioteket kommer sedan ligga ute på Sweco Structures interna nätverk, så att detaljerna blir lättåtkomliga för de som är i behov av dem. / It is constructed inadequate detail solutions of buildings in the current situation. The carrying frame of the structure is often given priority while it is not given as much focus to solve the building physical aspects. The reason for the inadequate detail is also that the person doing the don´t has the right knowledge or time. In order to create an improvement, a tool is needed!  Knowledge and experience of how well the details are created already exists at the company, the difficulty is to spread the knowledge to those who are in need of it. The objective of this report is to create a methodology that will mark the start of an extensive work on the development of a detail library whose purpose is to spread building physical skills within the company and inspire constructors to construct good detail solutions. The library will include good building physical detail solutions which were analyzed according to the produced methodology. The method will allow to easily evaluate detail solutions, and to present them with calculated values and recommendations in detail library. Through interviews with designers and a comprehensive review of construction projects, has 7 detail solutions been selected to be examined, and then illustrate how the documents in detail the library will be presented. The examples will be seen in the report, and they will also serve as the embryo of the definitive and large detail library. Detailed library will then be placed at Sweco Structures internal network, so that the details are easily accessible for those who are in need of them.

To be able to handle tomorrows need for limited energy consumption we need to reduce our use of energy. The building sector stands for around 40 % of all energy consumption in the society. The government has put up a goal to reduce the energy consumption in our buildings with 20 % by year 2020 and 50 % by year 2050 compared with year 1995. To be able to do reach that goal we need a more energy efficient building stock. The main part of the energy used in our buildings is used for space heating. By installing ventilation systems with heat recovery on the exhaust air it is possible to use the heat-energy in the exhaust air to warm up the incoming air. This can contribute to a reduction in energy use. A ventilation system with heat recovery on the exhaust air is space demanding and there can be problems with finding enough space to do the installation indoors. Therefore it can be an advantage to place the aggregate and the ducts on the outside of the buildings climate shell. A placement exterior of the buildings climate shell or in an unheated space leads to thermal heat losses. The aim with this essay is to investigate how significant the heat losses are on exterior placed ventilation systems. The investigation has been done with help of theoretical calculations and measurements of the temperature difference in the ventilation ducts. Analysis has been made on life cycle costs on how to reduce the heat losses in an economic manner. To buildings, Höstvägen 14 and 22 in Växjö, which have been equipped with exterior placed ventilation systems have been studied. The two buildings have two different types of installation of the ducts. Our result shows that the heat losses through the ventilation systems on Höstvägen 14 and 22 are significant. The majority of the losses occur in the ducts. In the aggregate the thermal bridges in the framework accounts for the larger part.

The theme of the diploma thesis "Effect of energy care on building prices" is the design and assessment of several measures, two of which generally lead to lower heating costs. The diploma thesis deals with evaluation of the current state of the family house and determination of PENB before the construction modifications and subsequently after the construction modifications, defining subsequent measures for energy saving implementation, both in terms of energy, economic and also environmental.