Do-It-Yourself Interior Painting Latex, or water-based paints, are usually used where there won’t be much need for washing. Enamels, or oil-based paints are used for woodwork and other areas where there might be a lot of hand prints. They are easy to clean because of their glossy finish. You’ll find a lot of enamel paint in bathrooms and kitchens for this reason. To estimate how much paint you’ll need, multiply the perimeter of the room by the height of the walls, which will give you the square footage of your room. For ceilings, simply multiply the length by the width. A gallon of paint typically covers 350-450 square feet. You’ll want to overestimate a bit to account for later to.....