Mankind strives for accomplishing the mutually agreed goals in Agenda 2030 where the thirteenth goal is to stop climate change. The amount of sand used in several materials is of great importance to the environment. Sand is a crucial component when producing flat glass, and one way of decreasing the construction sectors impact on the climate change is recycling of old flat glass. The study investigates the potential for an easier reuse of flat glass. The purpose of the thesis is to increase the reuse of flat glass and thereby reduce the climate impact from the construction sector. The aim is to bring forth a crosslist for reuse of flat glass, to find out if the bending strength in an old glass can achieve the requirements of today's standards and to make an overall calculation of the costs andthe enviromental savings when reusing flatglass. Several methods were used to achieve the aim, namely a literature study to gather information, dialogues that give a range of how different aspects can be valued and abending strength test that show the reused flatglass´s ability to withstand external pressure. The overall costs and the enviromental impact were also calculated. The result shows that the crosslist encounters for the properties being fulfilled in a reused window, given that the performer has a certain knowledge. The bending strength test showed that the roughly 60 year old flat glass did achieve the requirements and can therefore be used as a product in a new building. The dialouges enlighted the greatest obstacles for reusing flat glass as lack of knowledge and supply. More specific problems while using old flat glass is the matters of energy and guarantee which are essential when deciding if reuse is possible and is problematic for whoever tries to upgrade a window that is not reaching its specified requirements. The requirements if a window is to be reused or not in a specific way is a part of thecrosslist where the properties are categorized from 1 to 3 where 3 has the lowest performance but still achieves the minimum requirements. The possibly changed strength of the tested flat glass in terms of age is difficult to assess as there is no new reference object with a similar thickness to compare with. The overall calculations of costs and environmental impact shows that large savings can be made . The study show the possibilities of how a flat glass can be made by reusin flat glass. Nonetheless, more deep diving studies need to be deducted within the area but perhaps in the long term the study may contribute to increasing the reuse of flatglass.

I detta examensarbete kommer vi göra en kunskapssammanställning som kan geverksamma inom byggbranschen en god överblick av glas ur ett bärande perspektiv, där vi lyfter fram några av de forskningar som bedrivits i Sverige. Syftet är att undersökaforskningens utveckling kring glas som ett bärande element och få en djupare inblick i hur långt kommen forskningen är, samt varför glas inte används i lika stor utsträckning som andra bärande element. Arbetet kommer även undersöka vilka fördelar respektivenackdelar det finns med materialet som bärande element. Vi har valt att intervjua forskareinom området för att få en aktualiserad och tillförlitlig kännedom, samt kopplat denna tillrelevant forskning och litteratur. För att även få en inblick i vilken kunskap och åsikterverksamma personer och studenter inom byggbranschen har gällande användningen av glas som bärande element, har vi utfört en enkätstudie i samarbete med Glafo –Glasforskningsinstitutet. Denna enkätstudie har riktat sig till verksamma arkitekter,ingenjörer/konstruktörer och andra verksamma inom byggbranschen, samt studerandeingenjörer och arkitekter. Utifrån vår enkätstudie kunde vi konstatera att majoriteten inteanser sig ha en god kunskap kring glas som bärande element och att många även ärfrågande kring dess möjlighet att fungera som ett bärande element på grund av materialets egenskaper.Vi kunde även konstatera att forskningen kring glas som ett bärande konstruktionsmaterial går framåt då flertal forskningar gjorts inom området. Forskningen tittar framförallt på glasets infästning mot andra material, som i många fall kan vara problematiskt på grund av materialens olika egenskaper. Man tittar även på glasets bärande egenskaper då den utsätts för last. Ännu har man inte uppnått målet med att ta fram s.k. eurokoder för dimensionering av glasets bärande möjligheter. Detta gör det svår för glaset att slå igenom som ett bärande element, vilket innebär att man inte har samma möjlighet att använda glaset i den utsträckning som med andra material. Kostnaden att bygga med glas är också en aspekt som måste tas i beaktning, då det många gånger blir dyrare att välja glas istället för andra material. Detta på grund av saknandet av dimensioneringsklasser samt prefabricerade glaselement.Slutligen kan vi konstatera att glas som ett bärande element är på upptåg och väcker många nyfiknas intresse. Med materialet kan man skapa unika konstruktioner vilket kan ge ett arkitektoniskt upplyft. Glas som ett bärande element bör dock inte användas som ett primärt konstruktionsmaterial, utan i ett sekundärt avseende på grund av dess spröda brott. / The purpose of this degree project is to investigate the development of researches andstudies around the glass as a structural element. We want to gain a deeper insight into why glass as a structural element is not used as much as other structural elements, and what advantages and disadvantages there are with the material. To be able to do this we have been interviewing researchers with knowledge of glass in constructions and read different studies and literature. We choose to do a survey in cooperation with the Swedish Glass Research Institute – Glafo to achieve a good knowledge of what active workers and students in the construction industry thinks about glass as a structural element and what benefits they see with the construction alternative. According to the result of our survey the majority of the respondents do not believe they have enough knowledge about glass in structures and many of them questioned its ability to act as a supporting element because of the material's properties.We also note that research on bearing glass goes forward when several researches has been done in the field. The research is primarily looking at the glass attachment to othermaterials, which in many cases can be problematic because of the materials differentcharacteristics. It also conducts research to see how much load the glass can handle. They have not yet achieved the goal of producing so-called Eurocodes for the design of the glass-carrying possibilities. This makes it difficult for the glass to break through as acarrying construction material, which means that you do not have the same opportunity touse the glass in the extent as with other materials. To use glass in constructions is also an aspect that must be taken into seriously, when it often becomes more expensive to choose glass instead of other materials. This is because there are not sizing classes andprefabricated glass elements.In conclusion we can say that the glass as a load-bearing element is the antics and raises many of the curious interest. With the material we can create unique designs that can give an architectural lifted. Glass as a bearing material should not be used as a primary structural material, but in a secondary regard because of its brittle fracture.