Most liquids are denser in their solid form than liquid. That certainly applies to metals.
Water is, as Doc Al said, very unusual. Because of its unusual crystaline structure, It becomes less dense just as it freezes. If you were to reduce the temperature of ice even more, then it would become denser.
And, to quote Doc Al, "Good thing, too!" If water did not become expand as it freezes, ice would not crack rock, converting it to soil in which things can grow, there would not be a pocket of unfrozen water at the bottom of lakes in which fish could survive the winter, etc.