Some people enjoy painting the house; for others it’s a chore. But it must be done occasionally. One reason is appearance. An even more important one is protection of the wood or other exterior surfaces. Wood rots when it is not fully protected by paint or other finishes, and rotting or water-soaked wood allows moisture to reach the interior, where it can cost costly damage. Some metals rust when not protected; others develop a corrosive wash that stains surrounding surfaces. Delay, when repainting is needed, can also mean extra work when you finally do paint. Old paint that has blistered,cracked, and peeled will have to be removed before new paint can be applied.
There are a number of different types of exterior paint; however, selection doesn’t have to be a problem.
First, consider the type of surface – wood, metal, or masonry. Some paints can be used on all three; others on two. Condition of the surface is also important. Old chalky surfaces, for example, are not generally a sound base for latex or water-based paints.
Next, consider any special requirements. For example, non-chalking paints may be advisable where chalk rundown would discolor adjacent brick or stone surfaces. Mildew may be a problem in your area; mildew-resistant paint is available. Lead-free paints can be used in areas where sulfur fumes cause staining of paints containing lead pigments.
Color is the third choice consideration, but it is mostly a matter of personal preference. Some colors are more durable than others, and some color combinations are more attractive than others. Your paint dealer can advise you on color durability and combinations.
House paint is a commercial term used to describe exterior paints mixed with many different formulations. It is the most widely used typeof paint. Formulations are available for use on all surfaces and for all special requirements such as chalk or mildew resistance. White is the most popular color. House paint contains two parts: a solid part (pigments) and a liquid part (the vehicle).
The paint is available in both oil-base and latex (water-base). The vehicle of oil-base paint consists of linseed oil with turpentine or mineral spirits as the thinner. Its vehicle consists of fine particles of resin emulsified or held in suspension in water.
Through the years, exterior latex paint has developed to the point where it now accounts for a significant portion of the house paint market. There are a number of reasons for this, and the primary one is the cleanability of latex both during and after painting. Brush, tool, and spillage clean-ups require only tap water. Total drying time is only two to three hours, and drying to a dust-free surface takes only about thirty minutes.
Other advantages of latex paints include easier application, less pull on the brush, usually better color retention, and resistance to alkali and blistering. Also, they can be applied in humid weather and to damp surfaces.
Another type of water-base paint has a vehicle consisting of a soluble linseed oil dissolved in water. This paint has the properties of both oil-base and water-base paints.
In repainting, it is advisable to use the brand and type of paint that was used previously if it has given good service. A change is necessary only if the paint proved unsatisfactory.