Interior Paints
When you go to the hardware store to buy paint, you will be directed to a different aisle depending on whether you are looking for interior or exterior paint. The distinction is not simply that they have different labels on the can. The two paints are made differently because the job of a coat of house paint outside home is only similar to what a paint on your living room wall is called upon to do in that they are both paint that cover up an unpainted surface.
Interior paint is a paint that dries harder and is more inflexible than exterior paint. This may seem surprising but when you think about the amount of use and contact interior walls have with the family, pets, vacuum sweepers and many other kinds of activities that happen in those rooms of your home, the paint inside the house must be pretty tough. Outdoor paint doesn’t endure direct contact nearly as much. But the colors must be of a different make up because outdoor paint is more prone to fade after years in the sun. In addition, exterior paint has to be softer so it can “breathe”, which is to say that it must be able to expand and contract and to survive extremes of temperate that would destroy interior paint.
Paint you use on the outside of your house is not made to be washed as often as paint that is used inside the home. This makes sense because the walls of the various rooms of your house are far more susceptible to spills and stains from accidents that might happen. Interior paint also does not chip as easily which makes it a good base for walls that will often hold paintings and see changes in décor from time to time.
In many other respects, the two types of paints are similar in composition. The number of coats and how well the paint adheres to the surfaces they are applied to are also virtually identical which means that the methods and tools you use for painting inside can be reused outdoors as well. However, it would be a mistake to try to use one kind of paint in the other environment. For one thing, paint for the outside of your home is not made for life inside and there are issues of ventilation and safety for the family if the wrong paint is used indoors.
Putting interior paint on the outside of your house is not dangerous but it is foolhardy simply because house for indoor walls will not endure the rigors of outdoor temperatures and the exposure to the sun that you will see outside. So even if you have leftover paint of one of the types, do not mix it with the other kind of paint and don’t “get creative” by trying to economize using exterior or interior paint on the wrong surface. It simply is not a good idea.