Dog mat for concrete flooring

Our bedroom floor is made of wood slats so it is not cold nor warm, just right for the dogs to sleep. But in the living room where the dogs stay during the daytime, the concrete tiles are cold to the touch even if the room temperature is at 37 degrees C. We have provided a sleeping mat for our dogs so their bodies wouldn't be directly exposed to the cold tiles. However, it seems that they are more comfortable with the tiles for they don't want to lie down on the mat even if the weather is kinda cool. My husband bought a linoleum for that purpose but our dogs seem to avoid that too.