Em Dome 850mm Double Glazed Clear Fixed Circular Dome & Curb Description Em-Domes are quality thermoformed rooflights, designed to make optimum use of natural light. They are offered in a wide range of sizes, shapes and glazing options to meet virtually any specifier and client requirement. Properties Double Glazed: Light transmission - 77%. Solar heat gain factor - 69%. Sound reduction (db) - 20. Thermal transmission (w/m2k) - 2.68. Triple Glazed: Light transmission - 70%. Solar heat gain factor - 60%. Sound reduction (db) - 22. Thermal transmission (w/m2k) - 1.78. High security screwbolts Unique to the Em-Dome are the patented high security screwbolts, supplied factory fitted as standard to all units. Once installed, the fixing cannot be removed using common tools. The screwbolt provides a high level of resistance to tampering or forced entry. The fixing screw or bolt is sleeved within the body of the screwbolt which avoids pressure being exerted on the rooflight glazing as the fixing is tightened. This virtually eliminates the risk of stress fractures caused by over-tightening. Thermoformed Glazing Em-Domes are thermoformed from polycarbonate sheet and are available in single, double and triple skin plus certain sizes available in quad skin or Eco multiwall construction. Polycarbonate is virtually unbreakable, with an impact strength up to 250 times greater than glass. Glazing Options Em-Domes can be supplied in clear, opal diffused, bronze or ‘Heat Reflect’ (which reflects up to 68% of the heat radiation) glazing. All polycarbonate Em-Domes have a minimum 3 mm thick glazing. Acrylic Em-Domes have a minimum 3mm outer skin. Inner skin thickness varies according to the dome size. Em-Curb Upstands Em-Curbs are designed to be used in conjunction with Em-Dome rooflights to provide a thermally broken interface which in turn helps to improve the overall thermal efficiency of the roof. Em-Curbs represent excellent value for money, enhance the overall appearance of the rooflight and are prefinished white internally, therefore requiring no further decoration. Splayed Em-Curb upstands give an excellent spread of light through the room whilst the vertical units are available where the dimensions of the roof aperture need to be maintained. The standard Em-Curb is made from extruded white PVC-u. The multi-chambered construction gives an exceptionally robust and thermally efficient performance. This curb is suitable for most roof finishes and is available in heights of 150, 300 and 350mm with other heights also available. All ventilation, access hatch and smoke vent options can be used in conjunction with Em-Curbs. Em-Curbs can also be supplied in GRP which have integral 10mm polyurethane foam insulation and robust dome fixing and mounting flanges. They can be used with most roofing materials. Avaliable Upgrades • Triple glazed • Opening hinged frame & spindle • Electric opening • 300mm high PVC Upstand