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Building energy performance has always been important in the cold climate of Sweden, Norway and Finland. To meet the goal that all new buildings should be nearly zero-energy buildings by 2020, set in the EU directive 2010/31/EU [1] on the energy performance of buildings (EPBD recast), the building sector in Europe now faces a transition towards buildings with improved energy performance. In such a transition, a discussion is needed about the objective of the improvement – why, or to what end, the building energy performance should be improved. The objective of improving building energy performance is often a political decision, but scientific research can contribute with knowledge on how the objectives can be achieved.

This thesis addresses how the indicators used in the requirements used to achieve building energy performance in Sweden, Norway, and Finland, and the methods used to evaluate these requirements, reflect building energy performance. It also addresses difficulties in achieving comparable and verifiable indicators in evaluations of building energy performance. The research objective has two parts: to review, compare, and discuss (i) requirements and (ii) evaluation methods used to achieve energy performance of residential buildings in Sweden, Norway and Finland. The work in this thesis includes reviews of the requirements used in national building codes and passive house criteria to achieve building energy performance, of methods used to evaluate compliance with such requirements, and of methods used specifically to evaluate the indicator Envelope Air Tightness.

The results show that different sets of indicators are used to achieve building energy performance in the studied building codes and passive house criteria. The methods used to evaluate compliance with requirements used to achieve building energy performance are also different, but calculation methods are generally more often used than measurement methods. The calculation- and measurement methods used are often simple. A methodology to analyze the deviation between predictions- and measurements of building energy performance (the performance gap) was developed, to investigate the effects of different evaluation methods on different indicators used to achieve building energy performance. The methodology was tested in a case-study. This study indicated that the choice of method affects which parts of the performance gap reflected in the indicators Supplied Energy (see Terminology), Net Energy (see Terminology), and Overall U-value. Among the reviewed methods to evaluate air tightness, the Fan/Blower Door Pressurization is well known and preferred by professionals in the field. The results in this thesis may be useful when choosing indicators and evaluation methods to achieve different objectives of improving building energy performance and in the quest towards comparable and verifiable indicators used to achieve building energy performance.

Building energy performance has been important in Fennoscandia ever since the early vernacular houses, to combat the cold climate. Due to EU directive 2010/31/EU on the energy performance of buildings (EPBD recast), building energy performance has become even more relevant in northern Europe the last decade. Objectives for improving building energy performance may include reducing cost and CO2-emissions, increasing energy independency, and improving the indoor climate. Different indicators, criteria, and evaluations methods may be used to reach these objectives. This dissertation addresses indicators, criteria, and evaluation methods used to regulate energy performance of residential buildings in Sweden, Norway, Finland, and Russia. Four research objectives are covered: (RO1) comparing criteria and evaluation methods used to regulate energy performance of residential buildings in Sweden, Norway, and Finland, (RO2) studying the perspective of professionals with experience in building energy performance evaluation on (a) methods for evaluating envelope air leakage of residential buildings in Sweden and Finland and (b) potential energy performance indicators in the Swedish procurement process of multi-family buildings, (RO3) developing an approach for analysing the performance gap between design predictions and measurements that can be used to verify compliance with requirements on building energy use in practice, and (RO4) comparing the stringency of the energy performance criteria for residential buildings between the Swedish, Norwegian, Finnish, and Russian national building code. Many differences were found between how energy performance of residential buildings was regulated in the four countries. In Sweden, measurements were used more for evaluating building energy performance than in the other countries. As of 1st January 2020, the Finnish building code was characterized by its focus on the building heat loss and stringent energy performance criteria compared to the other countries. The Norwegian building code was characterized by a relatively narrow system perspective on energy performance, with no regulation of the energy production efficiency or energy source. The Russian building code also had a narrow system perspective but was also characterized by its focus on the form factor – the relationship between building volume and enclosing area. The practitioners wanted to minimize the influence from building operation and user behaviour on energy performance evaluations in the Swedish building procurement process of multi-family buildings. Hence, they preferred component-focused indicators or indicators with a narrow system boundary. An approach has been developed for analyzing the performance gap between design phase predictions and measurements. The approach can be used to verify the finished building’s energy performance, with minimal influence from occupant behavior and building operation.

Energiprestanda har varit en viktig byggnadsparameter i Fennoscandia ända sedan de första bostadshusen, för att bekämpa det kalla klimatet. På grund av EU-direktivet 2010/31/EU om byggnaders energiprestanda (EPBD recast) har energiprestanda i byggnader blivit än mer relevant i norra Europa det senaste årtiondet. Målen med att förbättra byggnaders energiprestanda kan inkludera att minska kostnader och CO2-utsläpp, öka energioberoende, och förbättra inomhusklimatet. Olika indikatorer, kriterier och utvärderingsmetoder kan användas för att uppnå dessa mål. Denna avhandling behandlar kriterier, indikatorer och utvärderingsmetoder som används för att reglera energiprestanda för bostadshus i Sverige, Norge, Finland och Ryssland. Fyra forskningsmål omfattas: (RO1) att jämföra kriterier och utvärderingsmetoder som används för att reglera energiprestanda hos bostadshus i Sverige, Norge och Finland, (RO2) att studera åsikter hos yrkesutövare med erfarehet av att utvärdera byggnaders energiprestanda om (a) metoder för att utvärdera luftläckage genom byggnadsskalet hos bostadshus i Sverige och Finland och (b) potentiella indikatorer för energiprestanda i den svenska upphandlingsprocessen av flerfamiljshus, (RO3) att utveckla ett tillvägagångssätt för att analysera skillnaden mellan beräkningar vid byggnadens design och mätningar som kan användas för att verifiera att energianvändningskriterier efterlevs i praktiken, och (RO4) att jämföra energiprestandakriteriernas stränghet för bostadshus mellan de svenska, norska, finska och ryska nationella byggreglerna. Många skillnader hittades mellan hur energiprestanda för bostadshus reglerades i de fyra länderna. Sverige utmärkte sig genom att använda mätningar för att utvärdera byggnaders energiprestanda i högre grad än de andra länderna. Den 1 januari 2020 utmärkte sig de finska byggreglerna genom sitt fokus på byggnadens värmeförlust och strikta krav på energiprestanda jämfört med de andra länderna. De norska byggrelgerna utmärkte sig genom ett relativt snävt systemperspektiv på energiprestanda, där energiproduktionens effektivitet och energikällan inte reglerades alls. De ryska byggreglena hade också ett snävt systemperspektiv men utmärkte sig också genom sitt fokus på byggnadens formfaktor - relation mellan byggnadens volym och den omslutande arean. Parterna i den svenska upphandlings-processen av flerfamiljshus föredrog att utvärdera komponentfokuserade indikatorer eller indikatorer med en snäv systemgräns, för att minimera påverkan från byggnadens drift och brukarbeteendet. En metod har utvecklats för att analysera skillnaden mellan beräkningar vid byggnadens design och mätningar. Metoden kan användas för att verifiera den färdiga byggnadens energiprastanda med minimalt inflytande från bukarbeteende och drift.