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NNE-kravets och materialvalens inverkan på prefabricerade ytterväggselement : Fallstudie för ett eluppvärmt tvåplans parhusStahre, Emma January 2016 (has links)
2015 kom ett förslag från Boverket gällande anpassning av Boverkets byggregler (BBR) till EU:s direktiv 2010/31/EU om nära-nollenergibyggnader. Förslaget innebär ett nytt sätt att beräkna specifik energianvändning och sänkta maxnivåer för densamma. I takt med att energianvändningen i bruksfasen av byggnaders livscykel minskar ökar vikten av att göra medvetna materialval, inte minst gällande de material som används för att uppnå de skärpta energikraven. Denna studie utgör en fallstudie där kravskärpningsförslagets inverkan på ett eluppvärmt parhus undersöks med avseende på transmissionsförluster genom klimatskalet, och vilken påverkan detta har på byggnadens prefabricerade ytterväggselement med träregelstomme. Väggens behövda isoleringstjocklek har undersökts genom U-värdesberäkningar och för olika isoleringsmaterial vars miljö- och klimatpåverkan även undersökts i form av GWP100 och energiåtgång i produktion. Beräkningar har utförts för tre beräkningsfall där klimatskalets delar tilldelats olika U-värden. Studien har funnit att val av fönster spelar stor roll för U-värdesfördelningen och därmed även för typväggens konstruktion, men att samtliga klimatskalsdelar behöver förbättras till U-värden i nivå nära värden för undersökta passivhus. Även det mest generösa beräkningsfallet för väggens U-värde genererade en ökning av isoleringstjockleken som skulle innebära att en ny konstruktionslösning krävs, då standarddimensioner för vanliga reglar inte räcker till. För isoleringsmaterialen visar studien att en balans mellan isoleringsförmåga och densitet har betydelse för materialens miljö- och klimatpåverkan, och att val av material av förnybar råvara och material som producerats med förnybar energi kan vara ett sätt att minska väggens miljö- och klimatpåverkan. I studien konstateras även att användandet av lättreglar istället för träreglar kan vara ett sätt att ytterligare minska isoleringens miljö- och klimatpåverkan genom att minska den behövda isoleringstjockleken. Användandet av lättreglar istället för träreglar sänkte den behövda isoleringstjockleken med 8,2 – 12,6 % i de beräknade fallen, och möjliggör att bygga väggelementen lika tjocka med isolering av träfiberskivor eller cellulosaskivor som med vanlig regel och isolering av stenull eller glasull med bättre isoleringsförmåga. / In 2015 the Swedish National Board of Housing, Building and Planning (Boverket) presented a proposal for the adaptation of the Swedish building regulations (BBR) to Directive 2010/31/EU on nearly zero-energy buildings. The proposal involves a new way to calculate a buildings energy use along with lowered levels for a new buildings maximum energy use. As the energy use in buildings related to the use of the building itself decreases, the importance of making conscious choices regarding the materials used to achieve these more stringent requirements increases. This study is a case study where the impacts of Boverkets proposal is investigated regarding heat losses through the building envelope of an electrically heated semi-detached house, as to what effect this has on the building's prefabricated external wall elements with wooden frame. The needed insulation thickness has been investigated through U-value calculations for various insulating materials whose environmental and climate impact is also investigated in the form of GWP100 and energy use in production. Calculations have been performed for three scenarios where the different parts of the building envelope have been assigned different U-values. The study has found that windows play a major role for the needed insulation thickness and therefore also for the construction of the wall, but that all parts of the building envelope need to be improved to U-values close to the values for passive houses. All investigated scenarios generated an increase in the insulation thickness that would mean a new design solution is required, as the regular dimensions for wood studs are not enough. Regarding insulating materials, the study has found that the balance between thermal conductivity and density is important for the materials impact on environment and climate. Furthermore, choosing products based on renewable raw materials and products produced with renewable energy can be ways to reduce the impact on environment and climate. The study also found that the use of lightweight studs instead of wood studs can be a way to further reduce the impact on environment and climate by reducing the needed insulation thickness. The use of lightweight studs instead of wood studs lowered the needed insulation thickness by 8.2 to 12.6% and enables wall elements with insulation based on renewable raw materials to be built with the same thickness as walls consisting of regular studs and rock wool or glass wool insulation, which in the study had the better thermal conductivity.
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De grundläggande rättsprinciperna vid direktupphandling : HFD 2018 ref. 60 och EU-rätten / The General Principles of Swedish Direct Awards : HFD 2018 ref. 60 and EU LawLignell, Elias January 2022 (has links)
This thesis examines the general principles in European Union (EU) public procurement law, as they apply to Swedish direct awards of low value, outside the scope of the EU procurement directives. A combination of Swedish and EU legal methodology is used to investigate two overarching themes. Firstly, the two different legal bases of the general principles, in the light of the Court of Justice of the EU’s definition of cross-border interest, as well as the Swedish implementation. Secondly, the central substantive consequences imposed by the principles on direct awards. The only national precedent on the subject, HFD 2018 ref. 60 of the Supreme Administrative Court, is both utilised and criticised against the backdrop of EU law to paint a picture of the principles’ inner workings in a direct award context. Pertaining to the first theme, an analysis of the applicability of EU primary law on direct awards is undertaken in order to distinguish the legal bases of the principles. If a contract is of certain cross-border interest, the general principles flow directly from EU law. In the absence of such an interest, the principles are exclusively based in Swedish law, which nationally extends the EU principles to all procurement (gold-plating). Overall, contracts valued below a quarter of the applicable EU directive threshold usually lack certain cross-border interest, unless there are concrete indications of the opposite. As a result, most direct awards fall outside the scope of EU law. An awareness of the legal bases of the principles is relevant to avoid breaches of EU primary law. It is argued that the Swedish gold-plated implementation of the general principles causes unnecessary uncertainty, and that separate national principles should be introduced outside the scope of EU primary law. As for the second theme, a thorough analysis concludes that the principles do not prohibit direct awards given without any exposure to competition, as long as the contracts are of low enough value. Direct awards can therefore be conducted through direct contact with a single supplier, in accordance with the legislative aims of the procedure. This may not be the case for social and other specific services of relatively high value. Nonetheless, the principles still affect direct awards, for instance in prohibiting flagrant cases of differential treatment without objective justification, based in arbitrary or corrupt decision-making. Unfortunately, these requirements are able to be circumvented due to the wide discretion given to procuring entities. On the other hand, if a direct award procedure is voluntarily advertised, the principles have greater practical significance. Still, the requirements in such cases are more lenient than in ordinary procurement procedures.
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