Purpose: The construction industry is affected by the progress of sustainability development. The United Nation has set up sustainability goals which presents in Agenda 2030. To meet these goals, the focus must be on the sustainability. The thesis has been conducted for actors in the construction industry should be given the basis for choosing floor that has low environmental impact and at the same time are economically defensible.

Method: To answer the questions formulations the work began with a document analysis and literature study to collect data. The collected data was used as a base for calculation and LCA. The calculation has been made with BidCon and the LCA with One Click LCA. Eventually an MCA was created to based on the literature study, LCA and calculations.

Results: The study shows that the wood flooring contribute to the least environmental impact but the concreate floor has lower costs. MCA shows that in terms of both economy and environment wooden flooring is most advantageous.

Implications: This conclusion in this report is to make it easier for actors to choose a floor system that is good from an economical and environment point of view. When a constructing a building, the coast of using concrete as a material is favoured but the lowest environmental impact is wood. Actors must therefore decide which priority is most important.

Limitations: The study is limited, only one floor layer with the selected material has been compared. All floors have been given the same lifespan and transport distances.

Keywords: Concrete floor, wooden floor, calculations, LCA, MCA