Masonry Walls and Ceilings. Interior masonry walls and ceilings above grade may, in general, be painted in much the same manner as plaster surfaces. Here again, it is necessary to allow adequate time for the masonry to dry before applying paint and, in addition, attention should be given to the preparation of the surface. When decorating a wall containing Portland cement (concrete, for example), it is essential to take precautions against the attack of alkali. For this purpose, alkali-resistant primers such as rubber-base paints may be used when oil paints are to follow.
Paints in powdered form require the addition of a liquid to prepare them for use. The manufacturer's directions as to the amount of oil, varnish, water, or other vehicle required should be followed.
Fire-retardant paints do not resist fires completely but its fire-resistance formulation prevents it from fire in spreading fast.
Water-thinned interior paints are calcimine, casein, resin-emulsion, and gloss water paints. Calcimine consists of powdered whiting and clay mixed with an animal-glue binder and a preservative. It cannot be recoated, but can be easily washed off before redecorating.
Plaster. New dry plaster in good condition, which is to be finished with a paint other than water paint, should be given a coat of primer-sealer and allowed to dry thoroughly before being inspected for uniformity of appearance. Variations in gloss and color differences in the case of tinted primers indicate whether or not the whole surface has been completely sealed. If not, a second coat of primer-sealer should be applied. If only a few "suction spots" are apparent, a second coat over these areas may be sufficient.
Take your time there is no rush. There is nothing wrong with having your project take a couple of weeks.
Practically every manufacturer has a "color system," a fat book of color chips with instructions for duplicating each chip. This is accomplished by intermixing cans of colored paint, by adding a concentrated color to a can of white or colored paint, or by adding concentrated color or colors to a can of neutral "base" paint. And for those who don't want any guesswork there's the Color Carousel that mixes the paints right in the store. Whatever the method, the result is a range of colors such as no amateur painter has seen.