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  • 1.
    Augustsson, Olof
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Svenska Turistföreningens fjällstugor - Uppvärmning, ventilation och elförsörjning2014Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    STF is constructing a single-storey house. The house is 279 m2, of which about a third arecommon areas with kitchen, living room, toilet, hygiene and drying room. It’s planned to be 10bedrooms with 24 beds. The assignment is to examine whether it is possible to meet up with thedemands of the indoor climate in terms of heating, ventilation and electricity needs where thepossibility of external power is not available. The report also present calculations and informationthat highlights the possible energy saving measures and their effect on energy consumption. Thisis to provide a basis for planning the first Stensdal cottage but also other structures ininaccessible environment where external power is not available. The research question in thisreport is: How can a house in the isolated mountains meet the requirements for heating andventilation and to what extent can the local electricity needs met up by solar and wind energy?The work is structured as a problem-solving case study with exploratory and descriptive design.The results section is divided into two parts. The first estimated the energy loss of the buildingbased on insulation, heating and ventilation systems. The second part studied differentpossibilities in order to ensure energy consumption by using solar cells, wind, wood andgenerator. When comparing the FTX and exhaust air ventilation the total heat loss is about onethirdlower with FTX ventilation. The design heat loss becomes more than a third lower for asystem with FTX ventilation. From the analysis of energy consumption, one can estimate thetotal power consumption of 184-325 W. When calculating on energy production a power of 350W was used to meet the need by some margin. In the calculation of one of the two methods ofcalculation used in this report requires 564 m2 of solar panels to meet demand year round withjust solar cells. To meet the demand from March to September requires 25m2 solar cells. Thesecond method of calculation gives that it is impossible to cover all needs without any kind ofbackup power, at the same time this calculation method does not require the same amount ofsolar cells but requires that you install batteries. There is much uncertainty in how the windconditions are at the site. Therefore, it has not been possible to explore the potential for windpower generation. It is possible to meet the electricity demand caused by heating and ventilationsystems, with most of photovoltaic energy. This is particularly true for the open period from lateFebruary to late September. It is impossible to guarantee a 100 per cent access to electricity foroperating systems without using any kind of backup system. If the system is in operation all yearround it may require up to ten times as great facility of solar cells while demands for energysupplied from the backup system increases.

  • 2.
    Chryssanthou, Emanuel Chryssanthou
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Studie ifall en nybyggnad går att åtgärda med energisparande lösningar, jämförelse av olika isoleringsmaterial och med en investeringsbudget på 5-6 miljoner kronor.: Jämtlands räddningstjänst personalbyggnad2015Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Jämtland’s rescue center has an investment budget of 5-6 million SEK. At present time an exercise house is being built in Furulund and together with that building Jämtland’s rescue center is planning to build a house for recovery and for relief of clothing that may have been exposed to pollution and contamination. The aim of this thesis is to investigate if a new building is possible to construct on Jämtland rescue exercise area. In essence, the focus of this work has been to design two new buildings proposed with two sub-options for each proposal. The first option has focused on applying the use of portable welding fume extractors and the second alternative without portable welding fume extractor and how it compensates to the specific energy use. Further proposals include energy-efficient solutions and comparisons between different insulation materials. In addition, calculations have been made including these alternatives with regard to construction costs. The work has been based on a qualitative and quantitative approach. Calculations of the new constructions have exceeded the budget with 1-1.4 million SEK excluding VAT. The proposals have been designed with 375 m2 and 394 m2 of cross floor area. A saving of 7-9 kWh / year has been calculated for the options without portable welding fume extractors. If there is low air pollution content in the premises, an airflow  that exceeds 0.35l/s m2 can be used in the building, but an average airflow of maximum 1l/s m2 can be used when the specify energy consumption is calculated according to building and planning, the national board of housing. The specific energy consumption for premises with increased exhaust flow can be increased by 110 (qmedel-0:35) during these circumstances. The building expenses can thus be reduced significantly in order to achieve the requirements of the specific energy consumption of the building for example by applying less insulation, however, this contributes to increased energy costs.

  • 3.
    Danielski, Itai
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Energy performance of residential buildings: projecting, monitoring and evaluating2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Energy security and climate change mitigation have been discussed in Sweden since the oil crisis in the 1970s. Sweden has since then increased its share of renewable energy resources to reach the highest level among the EU member states, but is still among the countries with the highest primary energy use per capita. Not least because of that, increasing energy efficiency is important and it is part of the Swedish long term environmental objectives. Large potential for improving energy efficiency can be found in the building sector, mainly in the existing building stock but also in new constructions.

    Buildings hold high costs for construction, service and maintenance. Still, their energy efficiency and thermal performance are rarely validated after construction or renovation. As energy efficiency become an important aspects in building design there is a need for accurate tools for assessing the energy performance both before and after building construction. In this thesis criteria for energy efficiency in new residential buildings are studied. Several building design aspects are discussed with regards to final energy efficiency, energy supply-demand interactions and social aspects. The results of this thesis are based on energy modelling, energy measurements and one questionnaire survey. Several existing residential buildings were used as case studies.

    The results show that pre-occupancy calculations of specific final energy demand in residential buildings is too rough an indicator to explicitly steer towards lower final energy use in the building sector. Even post occupancy monitoring of specific final energy demand does not always provide a representative image of the energy efficiency of buildings and may result with large variation among buildings with similar thermal efficiency. A post occupancy method of assessing thermal efficiency of building fabrics using thermography is presented. The thermal efficiency of buildings can be increased by design with low shape factor. The shape factor was found to have a significant effect on the final energy demand of buildings and on the use of primary energy. In Nordic climates, atria in multi-storey apartment buildings is a design that have a potential to increase both energy efficiency (by lower shape factor) and enhance social interactions among the occupants.

  • 4.
    Danielski, Itai
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Measurements of heat transfer coefficient of external walls with different insulation materials2014Manuscript (preprint) (Other academic)
  • 5.
    Danielski, Itai
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Fröling, Morgan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    In situ measurements of thermal properties of building fabrics using thermography under non-steady state heat flow conditions2018In: Infrastructures, ISSN 2412-3811, Vol. 3, no 3, article id 20Article in journal (Refereed)
    Abstract [en]

    This study describes a quantitative method using thermography to measure the thermal properties of building fabrics that are subjected to non-steady state heat flow due to consistently changing meteorological conditions. The method includes two parts. First, the convection heat transfer coefficient is measured by thermography and heat flux meters on a small segment of the examined building fabric with uniform surface temperature. Then, thermal properties of large building fabrics are evaluated by thermography. The two parts are measured simultaneously. The method was tested on 140/160/190 mm thick massive laminated spruce timber walls of a test facility cabin located in Östersund, Sweden. The results varied by only a few percent in comparison to validation measurements performed with heat flux meters and in comparison, to values from the literature. Due to rapid changes in weather conditions the measured values had large disparity, but still a linear regression with low confidence interval was obtained. Obtaining an accurate value of convection heat transfer was important for achieving high measurement accuracy and, therefore, the value of this parameter should be measured. Other important factors to consider are solar radiation, reflected infrared (IR) radiation from nearby objects and the number of thermal images.

  • 6.
    Danielski, Itai
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Fröling, Morgan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Joelsson, Anna
    SWECO, Vastra Norrlandsgatan 10 B, Umea, SE 901 03, Sweden.
    The impact of the shape factor on final energy demand in residential buildings in nordic climates2012In: World Renewable Energy Forum, WREF 2012, Including World Renewable Energy Congress XII and Colorado Renewable Energy Society (CRES) Annual Conference, 2012, p. 4260-4264Conference paper (Other academic)
    Abstract [en]

    The shape factor of a building is the ratio between its envelope area and its volume. Buildings with a higher shape factor have a larger surface area in proportion to their volume, which results in larger heat losses in cold climates. This study analyzes the impact of the shape factor on the final energy demand by using five existing apartment buildings with different values of shape factor. Each building was simulated for twelve different scenarios: three thermal envelope scenarios and four climate zones. The differences in shape factor between the buildings were found to have a large impact and accounted for 10%-20% of their final energy demand. The impact of the shape factor was reduced with warmer climates and ceased with average outdoor temperature 11ºC-14ºC depending on the thermal envelope performance of the buildings.

  • 7.
    Danielski, Itai
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Nair, Gireesh
    Umeå University, Department of Applied Physics and Electronics, Sweden .
    Joelsson, Anna
    SWECO AB (publ), Umeå, Sweden.
    Fröling, Morgan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Heated atrium in multi-storey apartment buildings, a design with potential to enhance energy efficiency and to facilitate social interactions2016In: Building and Environment, ISSN 0360-1323, E-ISSN 1873-684X, Vol. 106, p. 352-364Article in journal (Refereed)
    Abstract [en]

    The design concept of conditioned atria gains increasing popularity in commercial and service buildings all over the world, but is still not a common building design in the residential sector. This study investigates the potential of such design in residential buildings in Nordic climates as means to enhance both energy efficiency as well as social interaction among residents. Energy modelling was used to compare energy efficiency among designs of residential buildings with and without atrium and to identify important design parameters. Social interaction was analysed, based on a survey evaluating the perception of residents living in an existing multi-storey apartment building designed with a heated atrium in the north of Sweden.

    The results show that heated atrium in Nordic climates have a potential to reduce the total final energy demand while at the same time increase the conditioned space of the building. To positively impact energy efficiency, the atrium should fulfil three requirements: (i) it should be designed to reduce the shape factor for the whole building; (ii) it should have the minimum glazed area that comply with the building requirements concerning natural light and visual comfort; and (iii) adjustable solar shading should be installed in the atrium’s façades to avoid unwanted overheating. The survey results indicate that the additional space created by the atrium has a potential to facilitate and promote social interaction among residents and to increases a sense of neighbourliness and belongingness, which are often discussed as important parameters in relation to social sustainability.

  • 8.
    Danielski, Itai
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Weimer, Kerstin
    Mid Sweden University, Faculty of Human Sciences, Department of Psychology.
    Krook, Malin
    Mid Sweden University, Faculty of Human Sciences, Department of Psychology.
    Atria: en design för hållbara bostäder i ett nordiskt klimat2017In: Hållbarhetens många ansikten: samtal, forskning och fantasier / [ed] Edith Andresen, Gustav Lidén, Sara Nyhlén, Sundsvall: Mid Sweden University , 2017, p. 47-54Chapter in book (Other academic)
  • 9.
    Dodoo, Ambrose
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Gustavsson, Leif
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Sathre, Roger
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Impacts of end-use energy efficiency measures on life cycle primary energy use in an existing Swedish multi-story apartment building2011In: World Renewable Energy Congress 2011, Linköping, Sweden, May 8-11 , 2011Conference paper (Refereed)
  • 10.
    Dodoo, Ambrose
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Gustavsson, Leif
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Sathre, Roger
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Life cycle primary energy analysis of conventional and passive house buildings2011In: SB11, World sustainable building conference, Helsinki, Finland. October 18-21, 2011, 2011Conference paper (Refereed)
  • 11.
    Dodoo, Ambrose
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Gustavsson, Leif
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Sathre, Roger
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Life cycle primary energy perspective on retrofitting an existing building to passive house standard.2010In: SB10, Sustainable Community, Espoo, Finland, September 22-24, 2010., 2010Conference paper (Refereed)
  • 12.
    Dodoo, Ambrose
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Gustavsson, Leif
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Sathre, Roger
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Life cycle primary energy use of an apartment building designed to the current Swedish building code or passive house standard.2010In: Passivhus Norden. Aalborg, Denmark, October 7- 8, 2010., 2010Conference paper (Refereed)
  • 13.
    Eklund, Staffan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Utveckling av hållbara och energieffektiva attefallshus2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    There are plans on constructing a new sort of house called attefall with high ambitions considering sustainability and energy efficiency for demonstration and testing purposes on campus Östersund, Mid Sweden University. Attefall is a type of house limited to 25 square meters that requires no building permit, as to recent decisions. Wall construction will consist of glulam timber from Glulam. For foundation and roof, a constructions system consisting mainly of foamglas made by Koljern, will be used.

     

    Literature studies within the subjects of sustainable building, energy systems and building regulations have been performed. As have calculations to determine the average heat transfer coefficient and specific energy usage for comparing with current building regulations. A model of the house was made to ensure chosen energy systems would fit within the limits of an attefall-house and still accommodate a home.

     

    This thesis examines the buildings thermal envelope in regards to current construction requirements. Manufacturing above building materials is quite environmentally friendly but the insulation properties of glulam bring difficulties when confronted with building requirements, however, log homes have a heat retaining ability which evens out temperature oscillation and contributes to lower the energy usage.

     

    The thesis also examines which renewable energy sources are suitable for this type of house. Hot water for heating and domestic water is generated with a system consisting of a solar hot water system, solar collectors and storage tank with integrated immersion heater, connected to a woodstove which heat air as well as water. A hybrid solution made up of a wind turbine and eight photovoltaic panels connected to the grid enabling selling excess production and buying when needed.

  • 14.
    Eriksson, Andreas
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering. Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Brandteknisk dimensionering av oskyddade träförband: En jämförelse mellan Eurocode 5 och alternativa metoder2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 15.
    Eriksson Nygren, Karl
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Energianvändande i bostadshus: En studie i byggnaders energibalans2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 16.
    Fröling, Morgan
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Nyström, Ingrid
    CIT Industriell Energianalys, Göteborg, Sweden.
    DISTRICT HEATING AS PART OF THE ENERGY SYSTEM: AN ENVIRONMENTAL PERSPECTIVE ON ‘PASSIVE HOUSES’ AND HEAT REPLACING ELECTRICITY USE2010In: Proceedings of 12th International Symposium onDistrict Heating and Cooling, September 5th –September 7th, 2010, Tallin University of Technology, Tallinn, ESTONIA, 2010, p. 202-205Conference paper (Other academic)
    Abstract [en]

    Energy use for space heating, hot tap water and otherheat use at comparatively low temperature levelsrepresent a substantial part of the total energy use inSweden and countries with similar climate. It is thus ofimportance to meet this demand in a way generating assmall environmental impact as possible. However, it ispossible to create a system with higher environmentalimpacts with energy efficient buildings compared toless energy efficient buildings through choice of lessgood energy carriers. It is not enough that theindividual parts of a system are good and efficient togive a low environmental impact; the parts must beconnected into the system in a good way.From environmental perspective energy efficientbuildings and district heating don‘t oppose each other– good parts connected in a good system will give anoptimal. The results from the study of the three items ofhousehold equipment show possibilities for districtheating to be an alternative with good environmentalperformance, but not under all heat generationregimes.

  • 17.
    Gustavsson, Leif
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Dodoo, Ambrose
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Sathre, Roger
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Impact of ventilation heat recovery on primary energy use of apartment buildings built to conventional and passive house standard2011In: World Renewable Energy Congress 2011, Linköping, Sweden, May 8-11, 2011Conference paper (Refereed)
  • 18.
    Hashim, Fattah Mullah
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Jämförelse av trä- och betongstommar i flervåningshus2015Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 19.
    Hägg, Maria
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Varför byggs det inte fler småhus med stålstomme?2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In Sweden today, about 90 percent of all houses are built or under construction with a wood frame. Building houses with wood has been tradition for a long time and is also considered to benefit the environment. With modern architecture and the demand for more open space and flexibility in the house, there is an increased demand for materials with higher strength, which makes steel a possible option. Steel is predominantly used in hall buildings where large spans and high load capacity is required. Testing new solutions is thought to contribute to an increased cost, which is often a critical factor in the construction industry where they seek the lowest price. By comparing a small house with a steel frame to the same frame dimensioned in wood, the aim is to find out whether there is a specific reason why more houses are not built with a frame of steel. The study is based on literature and a design of wooden frame from existing drawings of a house with a steel frame. The price of the backing material was then based on a compilation of the material of each frame. Based on the weights of all the parts of the frame carbon emissions and energy consumption for each material where calculated. The properties of each material were compared based on the literature. The results show that both materials have their pros and cons. The frame of steel is about 55 percent more expensive than wood. However, the steel frame has a lower overall weight compared to wood, which is due to higher load-bearing capacity of the material and thus smaller dimensions. As of this, less space in the outer walls is needed for the frame of steel, thus providing an increased amount of insulation in certain parts of the body. Steel can also be considered a good alternative when it comes to moisture. Moisture is one of the most common problems in houses. Steel is an inorganic material and suffers neither of moisture nor fungus, which can result in poor indoor air and deteriorated strength of timber constructions. Energy consumption is relatively similar between the materials, as the production of steel is only 11 percent higher than wood. A major difference between the materials is however carbon emissions, which are 17 times higher in the manufacturing of the steel structure, compared to the wooden frame. The steel industry is constantly working to reduce their emissions, but as long as the carbon emissions in the steel industry are significantly higher than timber production, this could be a contributing factor in the choice of framing materials.

  • 20.
    Joel, Lindén
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Förtätning av tätort utan att bebygga orörd mark: En utredning för Eidar AB:s förutsättningar att förtäta Trollhättan Stad2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

     

    Abstract

    Concentration is an up-to-the-minute term as the Swedish population is estimated to pass ten million inhabitants in 2025. Concentration means that cities grow inward instead of outward as the trend long has been in Sweden. The city of Trollhättan is no exception and the city council passed a new layout plan the 10th of February 2014 with clear goals on concentration and increased sustainability. The layout plan states that the city should grow with 14 000 inhabitants and that 7 000 new homes are needed in 2030 to meet this growth. In response to the layout plan, Eidar AB, the semi-public housing body of Trollhättan, has decided to produce at least 1 000 new homes until 2030. The purpose with the survey has been to find out what qualifications Eidar AB has to concentrate the city of Trollhättan without building new homes on unused land, as well as how Eidar AB can contribute to sustainability in Trollhättan. The method for the survey has been to through literature studies collect different types of data, interviews have provided knowledge from experts in the construction industry, analysis of archive material and observations within the housing stock of Eidar AB has provided clarity of the opportunities available in the existing housing stock. The study has demonstrated that there are a number of opportunities with concentration through vertical addition. Buildings that face renovation can advantageously be selected since vertical addition opens up for rise in standards such as change of sewage pipe system, improvement of energy installations, increased availability and the possibility to install elevators. The conclusion that can be made from the study is that the actual exploitation number that the study has presented covers 25-40% of the decision of Eidar AB to produce at least 1000 new homes before 2030, while it may also bring with it necessary renovation of existing housings.

  • 21.
    Jonsson, Anders
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Höga trähus med skivbeklädda träregelväggar som avstyvande element: En jämförelse mellan skivbeklädda träregelväggar och massivträväggar2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Extensions of buildings are a way to increase opportunities to create more housing or premises when areas on the ground aren’t sufficient. After the previous restriction on building timber frames higher than two storeys were removed, is it now possible to do an extension out of timber. Wood is a light material that is suitable for an extension because strengthening of the existing building doesn’t have to be as comprehensive as with a steel- or concrete frame. A high building needs to be stabilized against horizontal forces. One way to do that is to design walls as shear walls. A shear wall is a wall that is designed to transfer loads to the underlying floor. The purpose of this study has been to, by calculations, present if it is possible to design a system with shear walls by either wooden studs covered with boards or solid wood panels that can transfer the horizontal loads to the existing building. The building that has been studied is a fictional eight-storey extension to an existing 15 meter high building that was built in Östersund. The calculations have been done by hand with theory based on Eurocode and Massivträ. Handboken. 2006. The study showed that it is possible to design shear walls both of wooden studs covered with boards and solid wood panels where both wall types managed to bring down the horizontal loads to the existing building. It turned out that the walls of solid wood panels can handle the loads by a wide margin and that it was the joint between the panels that needed to be designed differently for different floors of the building. For the wall made of wooden studs covered with boards, it is required a tight spacing for fasteners between boards and studs on the lower floors to handle the loads. That means that the design of the joint must be carefully designed with respect to the smallest screw distance when the inner board is perforated by the fastener for the outer board. Keywords: Structural stability, Timber structures, Sheet action.

  • 22.
    Jönsson, Arne
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Optimal heating capacity for a cold period with constant temperature2001In: PROCEEDINGS OF THE 4TH INTERNATIONAL CONFERENCE ON INDOOR AIR QUALITY, VENTILATION AND ENERGY CONSERVATION IN BUILDINGS, VOLS I-III, HONG KONG: CITY UNIVERSITY HONG KONG , 2001, p. 1001-1008Conference paper (Other academic)
    Abstract [en]

    This is an economic analysis of indoor temperature and of short changes in indoor temperature. The loss of benefit is higher during short involuntary changes than during a voluntary chosen indoor temperature. There will be a short involuntary change in the indoor temperature if the design heating capacity doesn’t cover the heat demand during a cold period. A one-day cold period is to short for design of heating capacity. The loss of benefit from low temperatures during one day will not be so high that it motivates a heating system. The increase of loss of benefit during short involuntary changes in indoor temperature may be 10 times higher than during voluntary changes, if the present Swedish design rules for heating capacity are economically optimal. The loss of benefit at the indoor temperature 22degreesC is 0.2 % of the disposable income per day of heating season. If the temperature is voluntary changed to 20degreesC the loss of benefit will be 0.9 %. A short involuntary change to 20degreesC will increase the loss of benefit to 3.1 %.

  • 23.
    Jönsson, Arne
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Principles for design of all-air systems2001In: PROCEEDINGS OF THE 4TH INTERNATIONAL CONFERENCE ON INDOOR AIR QUALITY, VENTILATION AND ENERGY CONSERVATION IN BUILDINGS, VOLS I-III, HONG KONG: CITY UNIVERSITY HONG KONG , 2001, p. 1129-1136Conference paper (Other academic)
    Abstract [en]

    This is a theoretical study on how to improve the optimisation of the all-air system. The economizer cycle was designed to distribute heat and cold with the supply air. To reduce the investment in heating and cooling capacity the outdoor air rate was reduced to the minimum outdoor air rate during high and low temperatures. This was as close to the economical optimum as possible with the control equipment available in the 1920-thies. An improved optimisation gives that the optimal outdoor air rate in the winter is higher than in the summer, because cooling is more expensive than heating. The optimal outdoor air rate is higher than the free outdoor air rate during free-cooling and the optimal outdoor air rate is higher than the minimum or acceptable outdoor air rate, except at the hot outdoor temperature. It is also possible to calculate better design temperatures, than the two and three design temperatures given in ASHRAE Handbook, if the derived equations are solved.

  • 24.
    Lidqvist, Markus
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Påbyggnad med CLT-bjälklag i kvarteret Höken 1: En studie av konstruktionsmässiga och ekonomiska förutsättningar2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Is cross laminated timber a suitable building material for adding storeys to a building? The purpose of this study is to examine how good an alternative CLT makes in comparision with other methods of developing new homes in urban areas. This study aims to a property developer and primarily to the client: AB Gotlandshem.

    The block Höken 1 was built in the beginning of the 1960s. The buildings of current interest are three houses with two stories and basement. These buildings are designated: B, D and F. The load bearing structure is constructed in varying materials. Two walls has been selected as especially interesting. They are examined closer through static analysis accordnig to EKS 9. The study concludes that they are sturdy enough to carry an added storey.

    The study also examines the ecomonic premises for adding a storey made from CLT. Separate costs are identified and compared. Naturally is the materials cost a separate cost in the choice between two different materials, but the study also identifies costs for mounting subfloor construction and installations as separate costs. The economic comparision indicates a possibility to cut costs by choosing subfloor constructins of CLT.

    The study shows that it is possible to add a storey to house B, D and F. Furthermore is CLT a good alternative from an economic viewpoint. The material has advantages that results in rational production methods. From this follows that CLT may be a cheaper solution for adding a storey.

  • 25.
    Liljegren, Fredrik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Magnusson, Emil
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Armeringsutformning: Utformning av armeringsdetaljer i platsgjutna konstruktioner enligt Eurokod 22015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    AbstractAs a designer you often come across detailed solutions in concrete structuresfor common recurring structural elements. Although the details are oftensimilar in appearance yet there is different design on the details. This isbecause the current standard, Eurocode 2, does not specify which solution isthe best solution, but leaves open to the designer to interpret.To work with these details to be carried out in a uniform manner and to ensurethat the design is done correctly according to current standards requires a clearcalculation template with the associated detail for the designers to follow.The purpose of this study has been to produce reinforcement design fordifferent kinds of details in site-cast concrete structures with associatedcalculation templates and references to current standards. Calculationtemplates have been developed through a qualitative literature review of eachdetail to find the failure case that detail may be exposed to. The demands ofthe Eurocodes for the current fracture processed and compiled into acalculation template.The details that have been checked are1. Column block2. Edge beam to exterior wall3. Wall foundation4. Column foundation5. Edge beam at cellar wall6. Slab connection to non-concrete outer wall7. Slab connection to concrete inner wall8. Slab connection to concrete columns9. Slab connection to concrete outer wallThe conclusion of the result was that the document designed with a summarydescription of the current design rules with references to current standardsrequired to detail that will be an extensive calculation template with referencesto current standards later supplemented with a fictitious calculation examplesand a more concrete and simpler calculation templates with references tocurrent standards with no clarification about any design rule in detail.Keywords: Concrete Construction, Eurocode, Reinforcement Details

  • 26.
    Lindblad, Helena
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Fallstudie av Ragnar Östbergs "Ett hem" med avseende på hållbarhetsaspekter: Framtagande av ny husmodell anpassad till dagens krav och standard2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Construction must become more sustainable. The residential sector accounts for a large proportion of carbon emissions and energy use. The use of chemicals in the construction industry is extensive. It has not always been like this. These changes have occurred mainly during the 1900s. This work will draw parallels to construction in the past and examine if we can learn something from how houses were built then. The aim has been to investigate whether a house from the last century can be seen as a sustainable house today. The goal is to combine the sustainable solutions from the past and the present, and achieve a modern house that reaches three-dimensional sustainability, and that is adapted to today's requirements and regulations for construction.

    A house from the early 1900s have been selected and studied. An important limitation is that the house has been studied only based on drawings and descriptions. No real house has been studied. The house that has been selected is Ragnar Östberg's model from the publication "Ett hem" (“A home” in eng.) from 1905.

    The result shows that Östberg’s house possesses many of today's sustainable properties. The house is ecologically sustainable, mainly because renewable materials are used. The house has a compact form, and the heating and ventilation systems are not dependent on electricity. Most aspects of sustainability can be found in the social area. What is mainly missing in Östberg’s house are properties associated with technical installations. The house must change to meet today's requirements. The building envelope must be airtight and well-insulated. The ground floor has to be designed to ensure access for disabled people. To accommodate the technical solutions and installations, a smaller extension must be done. The result shows that it is fully possible to take a 110 year old house model and adapt it to modern requirements and standards. The conclusion is that we can learn by looking back into the building history, in order to be able to build ecologically, economically and socially sustainable houses in the future.

  • 27.
    Lundmark, Pelle
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Dimensionering av trähuskonstruktioner enligt EKS och NA: En jämförelse mellan de svenska och norska nationella tilläggen till eurokoderna2014Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
    Abstract [en]

    The purpose of the introduction of Eurocodes is to create standardized rules and requirements for the design and dimensioning of structural elements, which should result in increased opportunities for companies to compete for jobs abroad. The main idea is that this competition then will lead to better quality and reduced costs in the construction industry. In addition to the eurocodes, every country is allowed to add their own national supplements based on their own knowledge and experience. Because of that allowance the national supplements creates some differences as to how the eurocodes are utilized regarding calculations and designs of structural components between different countries. An industry that is constantly growing on the market and looking for expansion abroad is prefabricated wooden houses. One of these markets could well be import and export between Sweden and Norway. To be able to expand abroad the engineers in the industry needs to be aware of the importing country’s national supplements to be able to fulfill the demands of these supplements. To show where the differences between the two countries national supplements exists a comparing study has been performed. The study has been based on three different calculations. The calculations consisted of the dimensioning of a truss, a floor joist and a column. The structural elements were calculated with both the Swedish national supplement, EKS, and with the Norwegian national supplement, NA. The study showed some differences in combinations of loads, load reduction factors, material values and a big difference as to how the respective national supplement handle requirements for floor joints. The design and calculations of the floor joints were found to be the most significant difference. The result of the study otherwise showed that countries as Sweden and Norway could benefit by develop common supplements to the Eurocodes as the difference apart from the design of the floor joints were relatively small.

  • 28.
    Lövgren, Emil
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Förespända betongbjälklag: Överhöjning i PRE-Stress2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Under the old calculation standards BBK the benefit was strength and various deformations according to standardized values ​​for the external circumstances. In the transition to the common eurocode in January 2011 these terms changed to specific values ​​of external circumstances and concrete strength for a more concrete custom calculation. This resulted in updated calculation software that have a problem with increased overbending with about doubled of the theoretical overbending. Tests to interpretation and calculation of shrinkage and creep conducted after a study of eurocode and a run through of the software PRE-stress basic knowledge to know how the program works and what values ​​affect deformations. A superficial examination of BBK conducted so comparisons between the old and new calculation standards were identified. The first results were varied and it was hard to notice a system. Following advice from another thesis localized values ​​that became more satisfying as calculated and given conditions. Expect the hike is a complex problem and given that manufacturers only provides a recommendation on how shrinkage and creep is allocated and eurocode can be interpreted in different ways, it becomes constructor individual interpretation and distribution that determines how large deformations PRE-Stress will present at calculations.

  • 29.
    Nilsson, Paul
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Jämförelse mellan olika träbjälklag2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Wooden joist slabs is a common type of floor in residential buildings. Higher demand and production of residential buildings increases the possibilities of profiting by optimizing the system of joists in a variety of areas. Spring and deflection is something most people can relate to since it’s not that uncommon to hear furniture rattle when you walk over a wooden floor. To remove the presence of those kinds of vibrations the system of joists have to be made stiffer than the standard joist construction that is used in today’s constructions. A system of joists has to be dimensioned, besides the tensile strength dimensioning, be dimensioned against excessive deflection and spring when someone is walking across the floor. To achieve a stiffer floor it can be constructed with higher rafter profiles since the deflection and spring decreases as the rafter is raised. Besides the rafter dimensions it is possible to change the materials in the slab to stiffer substitutes, this leads to a stiffer joist with a lower material consumption for the rafters. Solid wooden slabs are a type of self-supported slab that makes it possible to have a longer distance between the rafters. With these kinds of slabs it’s possible to build a floor with one big rafter in the middle of the room that carries one end of the slabs. The objects studied are two fictitious floors in a residential building with a span of four meters with two supports and the second floor eight meters with three supports. The floor is dimensioned according to SS EN-1990 and SS EN-1995-1-1:2004. The result from the calculations showed that it isn’t possible to increase the space between the rafters if the slab is a chipboard slab since the chipboard doesn’t have enough tensile strength. If the joist is constructed with solid wooden boards it is possible to increase the rafter spacing up to at least 2400mm, but the joist system gets a higher utilization if the rafter spacing is 1800mm because if the spacing is 2400mm the deflection is so high that the rafters get so little space to move on since the slabs deflection takes up more than half of the allowed deflection, this isn’t a good solution in practice, even if the rafter and the slab have enough strength to manage it the construction will be too high for a relatively small residential building. If the construction would be raised in an arch the rafters could be designed lower since in all the studied cases it was the deflection that was the weakest link

  • 30.
    Nilsson, Sofia
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Etablering av takstolsfabrik i Stugun: Produktionsförutsättningar och transporter2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Visions of broadening the horizons have interested a contractor from the region of Jämtland to seek new ways for the company, which led them to trusses manufactured in a factory. Previously the contractor has been ordered trusses from a manufacturer in Norrbotten because of the interest in a lower price than local producers have been able to offer. For a time they have had contact with a timber supplier who can offer industrial premises to rent. The proximity to the timber and the minimized transports has been attractive for an establishment.

    The study whose result is presented in this report intends to examine the economic costs of the establishment for the truss factory in Stugun. It also intends to investigate in which case the transport of the components of a truss can be reduced. To get the information that responds to these concerns has contacts been established with stakeholders that are involved in the industry in various ways. They have communicated their thoughts and ideas, which have helped to form the result in this case-study.

    The parameters included in the survey were the production conditions that apply to this type of industry. Also the prevailing conditions have left their mark. Costs for energy consumption or renovation of the premises have been excluded from the study.

    The economic basis for the production conditions which should be established shows that an establishment is possible. The price of the truss that the study brings out is in the same price range that many construction companies today pay for their trusses. When the target area of ​​the factory's production is Jämtland with vicinity can also transport distances be reduced compared with current alternatives.

  • 31.
    Nyström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Brandteknisk dimensionering genom beräkningar: - En jämförelse mellan två beräkningsmetoder med avseende på bärförmåga.2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Sammanfattning

    Dagens konsumtionssamhälle ställer allt högre krav på hushållning av jordens resurser. Tidigare studier visar på byggbranschens negativa inverkan på miljön. För att minska byggbranschens miljöpåverkan krävs implementering av nya och beprövade metoder. En potentiell metod är dimensionering av brandskydd genom beräkning som ger ekonomiska fördelar gentemot förenklad dimensionering, vilket visats i studien Kostnadseffektiv utformning av brandskydd av Johan Lundin och Fredrik Olsson (2000). Det finns idag två stycken vedertagna metoder för brandtekniskt dimensionering genom beräkningar ute på marknaden, metoden med reducerat tvärsnitt och metoden med reducerade egenskaper. Genom undersökning av beräkningsmetoderna är förhoppningen att utreda vilken metod som ger högst bärförmåga i brandfallet i förhållande till tvärsnittets dimension. Studiens kan fungera som komplement till Eurokod 5 och möjliggöra en snabbare och enklare hantering av brandteknisk dimensionering. Studien baseras på handberäkningar och uttalanden från specialister inom bygg- och brandsektorn. Handberäkningarna har utförts med hjälp av beräkningsprogrammet Mathcad Express och behandlat konstruktionsdelarna pelare och balk med varierande tvärsnitt och brandexponeringstid. Resultatet av handberäkningarna visade på att metoden med reducerade egenskaper erhöll högst bärförmåga i brandfallet i jämförelse med uttalande från specialister vilka tydde på att metoden med reducerat tvärsnitt är att föredra. Metoden med reducerade egenskaper har hög osäkerhet gällande indata och kan dessutom vara på väg bort från kommande versioner av Eurokod. Författaren har valt att gå efter sakkunnigas rekommendationer och dragit slutsatsen att metoden med reducerat tvärsnitt är att föredra framför metoden med reducerade egenskaper.

    Nyckelord: Träkonstruktioner, Beräkningsmetoder, Eurokod, Brand, Brandskydd. 

  • 32.
    Svärdby, Thor-Leif
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Brandskyddsarbete i Östersunds innerstad: En sammanställning och tillämpning av brandskyddsforskning i trästäder2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Östersund is a city which consists of a mixture of buildings from the 19th century and onwards. The habitation is protected as national interest, which increases the importance of its preservation. This study was conducted to provide input to Östersund Firedepartments project ”Safe city center”, in the form of collected advice and proposals for action, but it also aims to broaden the use of the content of the summarized reports.

    This report presents the collected proposals for actions based on the summary of reports, at both a general level but also targeted actions towards properties, gathered on the basis of the evaluation criteria of a building's fire protection level. To compile the general actions, a matrix was drawn up to clearly describe the frequency of the action. Targeted actions were gathered in subgroups based on 16 components used in the inventory of a building's fire protection level. The conditions in the city examined based on its history and accident statistics. Boundaries were draw up to only include actions towards properties and general advice.

    The study shows that the compiled general advice and targeted proposals for actions can be used in Östersund and even in other cities consisting of older buildings. It also shows that many targeted actions that meet the same objectives, may vary depending on the degree of cultural value. Most measures are simple and inexpensive to perform, and information is an important part of the work to raise awareness.

  • 33.
    Thofelt, Lars
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Försök med Levande filter vid Vaernes flygplats, Stjördal, Norge: rapport från försök den 25 och 26 september 19961996Report (Other (popular science, discussion, etc.))
  • 34.
    Thofelt, Lars
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Wadman, Sven
    Miljöanalys flygplatser: exempel Kramfors flygplats1996Report (Other academic)
  • 35.
    Thofelt, Lars
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Östlund, Börje
    Levande filter: ett försök med frisk luft inomhus1996Report (Other academic)
  • 36.
    Thofelt, Lars
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Östlund, Börje
    Levande filter friskar upp luften inomhus1996Report (Other academic)
  • 37.
    Widegren, Emma
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Attefallshus som plusenergihus?2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In order to reach the climate targets for 2020, building sustainable and energy efficient are the future of the construction sector. One way to build environmentally friendly is to build energy-plus-house. A plus house is a house that produces more energy than it consumes. To achieve that it requires a tight building envelope, low operating costs and energy supplied by either solar cells, solar panel or a combination of them. The aim of this essay is to look at three different wall thicknesses in solid wood and see if it would work to plan the Attefalls house as a plus energy house with any of these wall thicknesses. The aim is also to see if the installation to take advantage of solar energy is profitable to install. Guidelines are that the frame should consist of solid wood and the foundation of foamglas, the house must be designed to be placed at the campus in Östersund. It should be easy to assemble and disassemble and throughout the planning, high standards of sustainability should be aimed for. It is also important that the Attefalls house meets the accessibility requirements in the Building Regulations. This essay was conducted by literature reviews, interviews and calculations. The conclusion is that it is possible to build the Attefalls house as a plus energy house with all wall thicknesses. Accessibility requirements as student accommodation fulfilled. A combination of solar cells and solar panels proved to be the optimal solution. The installations of solar cells paid back in 11 years and the installations of solar panels at 32 years, which are both shorter than the building's lifetime and therefore profitable to implement.

  • 38.
    Widmark, Sofia
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Prefabricerade höghus: Planering, logistik och arbetsmiljö2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In Sweden there are plenty of land to build on which has led to a lack of interest of building high. It is only in recent years that hi-rise buildings have increased, particularly in the bigger cities. The purpose of this master’s dissertation is to contribute with knowledge about how the production of a hi-rise building should be planned and executed to generate an effective workplace with a safe work environment. Data was gathered through literature, interviews and observations. A prefabricated high-rise building can be built in a very short amount of time but that requires a particular and correct production plan. A cycle timetable has been used in all three of the studied cases. Visual management tools were used to give everyone an open overview of the working progress. To make a production profitable, it is required that the right amount of material is transported and handled with efficient means at the right time, the studied cases used the method Just-in-time. This together with thoroughgoing roads at the working site has created a flow of the logistics. The working environment is always critical at a construction site. Falling is the most common reason to fatal accidents within the construction industry and a very relevant risk when building high. On the studied cases the risk of falling has been prevented through scaffolds and security railings according to the rules of the Swedish work environment authority. This study has shown that a cycle time plan works well in a high-rise building project because the floors are similar to each other and can easily be divided into different cycles. Through visualizing the plan, all workers get involved and conflicts can be avoid because everyone is well informed of the conditions at the moment. It has also shown that a good flow on the logistics can be created through a well executed construction site plan which streamlines the deliveries and the handling of materials. Accidents at the work area can be prevented through safety gear, documented work preparations and risk inventories as a part of the systematic work for a safe work environment.

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