3-Seater Fabric Sofa FAQ's 1) What is the average size of a 3 seater sofa? 3 Seater sofa sizes can vary depending on the model, our 3 seater sofas all have dimensions on them so you won't be stuck for choice! We have size diagrams available for each model, so you wouldn't be stuck for couce when picking your 3 seater sofa size. 2) How heavy is a 3 seater sofa? Weight can vary with all 3 seater sofas, depending on the width, depth and height of our large sofas. However, the average weight for a 3 seater sofa is around 350kg. 3) How many cushions are on a 3 seater sofa? The number of cushions you will recieve on a 3 seater sofa can vary depending on the range and style of the sofa. We have 3 seater sabric sofas and leather sofas which have two cushions, but as classed as a 3 seater due to their size. Others have 3 seating cushions, this all depends on the range you choose.