5. Steam for Subfloors mineralesEn brake dry soils and minerals is very important to install a sheet of polyethylene with a thickness of 0.2 mm to prevent the remaining moisture from reaching the back of the laminate planks. Polyethylene foil acts as a steam brake. Keep in mind that the strips overlap min. 30 cm and paste them on the cutting edge. Under no circumstances should this sheet serves as a building insulation. Refer also to chapter Subfloors.
6 Dilatacionel substrate of laminated parquet boards is made of a material based on particles of wood that, as also, natural wood dilates according to climatic conditions. That is why it is important to maintain a corresponding distance (called expansion joint) towards all the walls and all fixed in the room objects. In addition they have to maintain expansion joints when you have an installation that exceeds the previously defined measures. (see the installation 7 standard). A too small expansion joint is the most common mistake for installations. Often not noticeable until the summer because in those months laminate flooring dilates automatically because of the high humidity of the air and temperature. Keep a minimum 8 mm expansion joint. With larger surfaces, this Board has to be greater.
Generally it can be said that: per metre of pavement requires a minimum of 1.5 mm of Board expansion on both sides of the room. (An example: A room with 5 m width = a minimum of 8 mm to each side of the room expansion joint). * Indicacion:min. 15 mm with a relative air humidity > 65%. Although the material installed only has contact with a wall or a fixed object can be the case that bulges up the floating floor. The weak points are the door frames, points of connection towards the stairs, heating tubes and closing profiles. Heavy as for example modules of kitchen objects or cabinets (pavement can move in these points solely to one side) require that on the opposite side of the room there is a Board of dilatation with twice the bandwidth.