There is a very easy way to check the type of paint used in your home. First, apply a small amount of rubbing alcohol or nail polish remover on a rag − preferably a different colour than your wall. Next, select a non-noticeable part of your wall or trim for the test and rub the rag in a small circular motion on one spot. If the paint comes off easily, it is latex (water-based). If there is no transfer to your rag, your wall is painted in oil-based paint.