This study was a final thesis, for the bachelor program in civil engineering at the University of Uppsala, which was made on behalf of Riksbyggen in Uppsala. A comparative study of two stain renovation methods; tradition pipe replacement and relining was done with an environmental perspective. A simplified life cycle assessment (LCA) was done according to the International Organization of Standardization (ISO) with the LCA tool Eco-indicator 99, in order to be estimate the impact on the environment. LCA is a method that follows a product or a system “from the cradle to the grave”, which means that all the environmental impact over a lifetime is considered. The work was executed by using a stairway with nine apartments in a house called “Uppsala Hus 9” as a reference object, which was provided by Riksbyggen. The house was a typical house from the so-called “Miljonprogram” and was restored with traditionally pipe replacem ent four years earlier. Interviews were done with the companies VBE Byggproduktion AB and Novada that works with traditionally pipe replacement and relining, in order to receive information about material consumption, equipment, transports etcetera for both methods. Where some information was impossible to obtain, assumptions were made. The processes considered within the study were extraction and production of materials, energy use of machines, transports, recycling and waste. The environmental categories that the study estimated were taken from Eco-indicator 99 and the categories were “human health”, “ecosystem quality” and “resources”. The conclusion of the study was that the traditionally pipe replacement had a greater impact on the environment than the relining. This was mainly due to the fact that the production of material with the traditionally pipe replacement was about 950 times larger than with the relining. The transport with the traditionally pipe replacement was about three times bigger than the transport with relining. The result of the v recycling was larger with the traditionally pipe replacement than with the relining which had none recycling at all. The energy use of machines was slightly bigger with relining than with traditionally pipe replacement. Some of the data was unreliable, which required us to make some assumptions. This resulted in some of the values being too high or too low. An example could have been that the use of machines for both of the methods was too high. Meanwhile, it should not affect the result too much, due to the fact that the use of machines for both methods almost cancelled each other out.

Efter politiska beslut byggdes cirka 1 miljon bostäder mellan åren 1965-1975. Dessa byggnader kallar vi idag miljonprogrammet och de utgör 25% av dagens bostadsbestånd. Renoveringsbehovet för dessa hus är överhängande och många fastighetsägaren står inför stora renoveringsprojekt såsom stambyten.   Ett stambyte innebär att vertikala vatten- och avloppsrör ersätts av nya. Ofta medför det stora åtgärder i badrummen och därför renoveras dessa i samband med ett stambyte. Den dominerande metoden för att genomföra ett stambyte med badrumsrenovering kallas traditionellt stambyte. Denna metod innebär att alla befintliga stammar och ytskikt i badrummet rivs och ersätts av nya.   ”Rum-i-rum”-metoden är en annan metod för att genomföra precis samma renovering men utan att riva bort de befintliga stammarna och ytskikten. Det nya rummet byggs upp inuti det gamla med nya ytskikt, stammar och ny inredning. Mellan det nya och gamla etableras en luftspalt som kopplas på den befintlig ventilationen.   I rapporten jämförs den traditionella metoden mot ”rum-i-rum-metoden” men hänsyn till kriterierna kvalitet, miljöbelastning samt kvarboende hyresgästers situation. Skillnader mellan metoderna identifieras och de ligger till grund för jämförelsen. För att samla information har intervjuer och litterära sökningar genomförts. Resultatet från jämförelsen ska kunna ligga till grund för ett beslut om huruvida den ena metoden ska väljas framför den andra.   Jämförelsen visar att skillnaderna mellan metoderna framförallt härstammar från förhållningssättet till arbetet. En traditionell badrumsrenovering utgår ifrån entreprenörens villkor och ”rum-i-rum”-metoden har hyresgästens behov i centrum. En sådan skillnad är att med ”rum-i-rum-metoden” spenderar entreprenören kortare tid i hyresgästens lägenhet jämfört med den traditionella metoden. Den traditionella metoden har dock stora anpassningsmöjligheter och det finns ingen begränsning i hur badrummet kan se ut.   Valet av metod bör ske med hänsyn till renoveringsobjektets egenskaper. Om hyresgästerna har behov av en smidig och snabb process för stambytet har ”rum-i-rum”-metoden fördelar. För projekt med tekniskt svåra omständigheter kan en traditionell badrumsrenovering med fördel väljas som metod. / After a political decision, about 1 million residential buildings were built between year 1965 and 1975. These buildings nowadays go under the name of “miljonprogrammet” and they represent 25% of all residential stock available. The need for renovation for these buildings is impending and many property owners foresee big investments in projects like renovation work on the drain systems.   When doing renovation work on the drain systems all old drainpipes are replaced with new pipes. This often causes a lot of damage on the bathroom and therefore these are included in the renovation project. The most common method for replacing the drain systems is called traditional renovation (“traditionellt stambyte”). In this method all drains and layers in the bathrooms are removed and replaced with new ones.   The modular bathroom is another method for a renovation of the drain system but there is no wrecking or tearing down walls going on. The new bathroom is built up inside the old one including new drains. The space between the new and old has the function of a ventilated air gap and is connected to the existing ventilation system.   This thesis are comparing the traditional way of doing a renovation on the drain system and the way of a modular bathroom renovation, regarding the criteria of quality, environmental impact and the situation for tenants. The differences between the methods will be identified and form the foundation of the comparison. A decision whether to choose one of the methods over the other can be made with knowledge from the results of the report.   The comparison shows that the differences between the methods above all originates from the approach to how the projects runs. The traditional way takes off from the contractors point of view and the way a of modular bathroom renovation use the tenants as their center of attention. A point that proves this is that a modular bathroom renovation spends less time in the tenants apartments comparing to the traditional way. One benefit with the traditional method is the ability to customize due to the need for the project.   The choice of which methods to use should consider the characteristics of the current set-up. If the tenants have the need of a quick and smooth process the way of a modular bathroom renovation has the advantage, the traditional method suits a more technically difficult project better.