In recent years the specification for the climate in museums and archives has become so strict that air conditioning has to be installed, though the scientific evidence of the need for such constancy of climate is very thin. The standards are rather based on what the best available technology can achieve, regardless of energy use and the need for constant surveillance of the equipment. Going to the opposite extreme, some buildings with no air conditioning perform very well, reaching the standard specification in relative humidity and getting close to it in temperature constancy. The key to achieving this stability is to reduce the air exchange rate, to give the structure considerable thermal capacity and to use porous, water absorbent materials for walls. However, the standards are also strict about the need for adequate air exchange rate to flush away internally generated pollutants and to remove patches of stagnant humid air. Stagnant humid air can be avoided by other means, such as ensuring temperature uniformity (which is already embedded in the standard). The usefulness of flushing out pollutants seems to be a good idea, but how much do the pollutants react with the stored materials in their immediate containers before they reach the larger enclosure of the room? The standard setters seem to be in a muddle about both the chemistry and physics of decay processes and about the possibilities inherent in simple changes to the building design, such as rounded corners and absorbent walls. We review the performance of existing buildings and extend our analysis to the design of new buildings.