It shall be unlawful to store, or to sell or offer for sale, any flammable or volatile liquids as defined in this Chapter in an amount in excess of one gallon in any building of frame construction, or any building other than a building of fireproof construction as defined in the ordinances of the Village; provided that this Section shall not be construed to prohibit the storage of such liquids in the fuel tanks of automobiles, or in tanks for heating systems installed in compliance with the provisions of the Village ordinances. (1968 Code, §21.131)