However they are stored, they should be kept as free as possible from the ravages of excessive heat and humidity. Air conditioning and dehumidifiers help here, especially in tropical areas and during the more humid months in many U.S. locales. Keeping stamps in unheated rooms, such as attics and garages, is unwise. Placing them near a basement furnace is courting disaster. It's also advisable to avoid, if possible, spots within a room that receive direct sunlight.
Sunlight can fade stamps, and the sun's heat can soften gum, causing mint stamps to stick together.
Albums and stock books should be stored upright, so that the weight of additional albums piled on top is avoided. Like people, stamps need to breathe once in a while. Regardless of where you store them, it is a good idea to take your albums and stock books off the shelf frequently and open them, page by page. Just a few moments of air circulation will help prevent gum and paper damage that can occur when stamps are left for weeks and months in an airless environment. Duplicates and other loose stamps may be safely relegated to something like the proverbial cigar box, providing the containers in which they are placed have no migratory glue, grease or wax that can affect them.