Document BpzNKpZyB5qn7wQ9MnjDybBL

Insulation Glass Blocks Pittsburgh Corning Corporation Grant Building, Pittsburgh, Pa. Distribution through Pittsburgh Plate Glass Company warehouses in principal cities and by the W. P. Fuller Company on the West Coast. Glass Blocks allow the economical E use of large glass areas, reduce heat loss in cold weather and materially door temperature of --14 deg is reached. Under similar conditions with single-glazed sash, moisture will begin to form when the aid air-conditioning. This is because eachoutdoor temperature reaches +33 F. PC Glass Block contains a sealed-in dead- air space that is an effective retardant to Solar Heat Gain heat transfer. The use of glass blocks for light-trans Thermal Insulation mitting areas results in a marked reduction in total solar heat gain as compared with Tests run by nationally recognized labora ordinary windows. This factor is of con tories have established the value of glass siderable advantage in buildings that are blocks for insulation of light-transmitting . properly air conditioned, but does not areas. These tests have proved that with eliminate the need for adequate ventilation glass block panels, heat loss is slightly less or shading in non-air-conditioned rooms. than half that experienced with singleglazed windows. In computing heat losses through panels for most design purposes, For data on solar heat gain through glass blocks see the table in the solar radiation it is recommended that a "U" value of section of this Guide--page 157. This 0.46 to 0.49 be used for all block sizes and table is for standard pattern glass blocks. face patterns. For complete data on heat transfer values see the section on heat transfer elsewhere in this Guide--page 115. PC Glass Blocks Aid Air-Conditioning Surface Condensation Due to high insulating value, condensation will not start forming on the room side of glass block panels until outside air has The three chief aims of air-conditioning-- temperature control, humidity control and cleansing of air are all aided by the use of PC Glass Blocks. Heat loss is less in winter--heat gain is less in summer. Ideal reached a temperature much lower than that necessary to produce condensation on single-glazed windows. The accompanying chart shows at what temperatures con densation will form. humidity conditions are much more easily maintained without undue condensation. Solar heat transmission and radiation are reduced. Dirt can't filter in, for each panel is a tightly sealed unit. Outdoor temperature required to produce condensation on the room side surface of PC Gass Block Panels. Sizes and Shapes Available PC Glass Blocks are 5* available in eight at"* tractive patterns, some of the patterns being designed for special control and direction of trans mitted daylight. For complete informa tion on the sizes and shapes of PC Glass Blocks, and for illustrations of the many patterns available, write the Pittsburgh Corning Corporation, Pittsburgh, Pa., or call the nearest Pittsburgh Plate Glass Company warehouse. For example, with inside air at 70 F and relative humidity at 40 per cent, condensa tion will not begin to form on the interior surfaces of a glass block panel until an out Additional technical data, including de tailed figures on thermal insulation, solar heat gain, surface condensation^ light transmission and construction data, will be furnished on request. 1122 1