The general construction of rooms containing sanitary fittings ought to be of the best. The floors-of ground-floor and upper rooms alike-ought, where possible, to be of concrete, the ingredients to be properly proportioned so that the material is practically impervious. In sculleries, lavatories, water-closets, housemaid's closets, etc, the floors may be finished with fine concrete, which will be all the better if carefully laid and polished after the manner known as terrazzo. Tiles and mosaic also make satisfactory floor surfaces. Such floors are, however, cold, and are not generally approved for bath-rooms-at any rate, in houses-although a simple remedy can be found in cork mats or strips of cork carpet or other movable floor-coverings, such as a light wood trellis. Sometimes the concrete is floated to a level surface with cement mortar, and when this is dry, cork carpet or linoleum is glued down to it. Cork carpet may also be glued and nailed to an ordinary boarded floor, and will render it practically impervious. Wood blocks form a suitable surface for bathroom floors, especially if of hardwood, wax-polished.

The walls of all rooms containing sanitary fittings ought to be faced with impervious materials, which will not absorb organic matter and can be easily kept clean. Glazed bricks are often used for the purpose, with the mortar-joints painted with enamel paint. Opalite and glazed tiles are also suitable, or the walls may be finished with Parian or other cement, and afterwards painted. In America large sheets of enamelled zinc, known as "mezzotile," are sometimes used; the smooth surface of the material, and the closeness and small number of the joints, are excellent features. Ordinary lime plaster covered with wall-paper does not form a satisfactory wall-surface, even when the paper is varnished. The angles of the walls ought to be rounded; special glazed bricks and tiles are made for the purpose. In hospitals the angles formed by the floors and walls and by the walls and ceilings are also rounded off, an arrangement which might with advantage be adopted in other buildings, as it facilitates dusting and sweeping, and reduces the possibility of accumulations of dirt.