Method for manufacturing a piece of furniture

A method for producing a piece of furniture selected from the group consisting of a seat, a bed, a table, said piece of furniture comprising at least one furniture component, said method comprising the steps of:

• making a blank of expanded polystyrene with a density between 15 and 25 kg/m3, said blank being configured to act as a core for said at least one furniture component;
• making an interface surface in said blank;
• making a rigid insert, wherein said rigid insert comprises having an engagement portion configured to engage with said interface surface of said blank and also comprises a connection portion opposite to said engagement portion;
• connecting said rigid insert and said interface surface so that said engagement portion is engaged with said interface surface and said connection portion is arranged opposite to said blank apart from said interface surface;
• and
• coating said blank and said rigid insert by at least one coating layer of polyurethane material, so that said at least one coating layer entirely covers said blank and partially covers said rigid insert with the exception of at least one exception portion of said connection portion and so that said exception portion is left free from said at least one coating layer and free from said interface surface,
• wherein said at least one coating layer has a hard and glassy consistency and said coating step arranges said at least one coating layer to coat said connection portion all around said exception portion creating a hard shell bridge which integrally connects said blank and said rigid insert along a joint line therebetween, allowing the rigid insert to be solidly and stably attached to the blank hard shell bridge and allowing said exception portion at the same time to be free from said interface surface and surrounded by said hard shell bridge.