Floor covering (I) for an animal house for beef animals and dairy animals comprises an elastomeric mat (2) which can be fixed to a floor or floor slat by screws (8). Rigid strips (6) are located at the base (7) of mat (2) for securing the screws (8) which are coverable by the mat when it is fixed to the slat. Mat (2) is designed for cleanliness and enhanced protection and comfort for animals. Flap valve (3) forms an openable flap valve along one longitudinal edge of the mat (2) to seal a gap between adjacent slats of a slatted floor to reduce the emission of gases and fumes emanating from a tank beneath the floor. The flap valve (3) allows waste material to pass through the slatted floor to the tank.