Abstract: A multiple-glazed window unit comprises a pair of glass sheets held in spaced relation to each other by a spacer and sealant assembly defining a sealed, insulating airspace between the sheets. The surface of the sheets facing the airspace has a protective surface. The spacer and sealant assembly is free of any desiccant. If desired, an opening may be provided through the spacer and sealant assembly to put the airspace in communication with the atmosphere external to the unit. In the stance where opposed openings are provided, and sized and configured to allow free movement of atmospheric air and water vapor molecules through the airspace to equalize airspace pressure and relative humidity with that of the external atmosphere, the protective surface is not needed. A filtering element is employed to minimize infiltration of liquid water, dust, dirt, and the like through the openings and into the airspace. The unit also comprises a sash retaining the unit within a structural opening.

Abstract: A triple glazed unit has the inner glass sheet mounted within a spacer and outer glass sheets mounted on opposed outer surfaces of the spacer. The peripheral edge portions of the outer glass sheets extend beyond the spacer to form a peripheral channel. A moisture-resistant adhesive fills the peripheral channel to seal the unit and provide dead airspaces between the glass sheets.