Glass Skylights

Series MSGS Glass Skylights 

The design concept behind the system is a separation of the internal pressure equalized drainage channels and the interior condensation gutters. All intermediate purlin and sill sections are installed in a shingled manner so as to drain into the rafters. This allows for seepage to be channeled to the exterior, condensation to be collected on the interior, with a positive barrier between the two. There is no direct contact between exterior pressure plates and interior structural members thereby yielding a positive thermal separation. Structural design requirements are achieved with a selection of rafters. These sections are have been professionally engineered to maximum deflections of 1/200th of the overall span. Pressure plates on vertical and upper horizontal members may be supplied with snap-on covers to conceal fasteners. Pressure plates on intermediate and lower horizontal members shall be of minimum profile, with exposed fasteners, in applications not exposed to direct view.

The Mac Series MSGS Skylight Glazing System is normally custom fabricated to suit specific design requirements. Aluminum framing may be supplied with clear anodized, bronze anodized, black anodized, two-component epoxy enamel, baked enamel or thermosetting fluoropolymer enamel finishes. The Mac Series MSGS Skylight Glazing System is specifically designed for use with glass. Glass may be single, double or triple glazed. Single glazed glass is always laminate or heat-strengthened laminate safety glass. Sealed units in double or triple glazing are always tempered glass on the outboard lite and laminate safety glass on the inboard lite. A variety of glass types including clear, tinted, reflective, low-emissivity and heat mirror are available.

Extruded aluminum rafter, purlin and sill sections each incorporate a set of pressure equalized internal drainage channels intended to equalize the pressure beneath the extruded aluminum pressure plates, with the exterior environment. All intermediate purlin and sill sections are half-lapped into a notch in the rafters. This shingled installation allows for any seepage of moisture through the exterior rain screen (pressure plates) to drain to the base of the skylight and out onto the roof. The pressure equalization assures that this drainage will occur under all conditions. All sections incorporate a continuous air seal at the inside face of the glazing panel. This system collects and controls any penetration of moisture without compromising the integrity of the air barrier. Interior condensation gutters are also incorporated in each section and are installed in a similar shingled manner. These interior gutters collect any accumulation of condensation from the interior surface of the glass and lead it to a large evaporation trough at the base of the skylight. As these gutters and the evaporation trough are situated entirely on the interior of the air barrier, they control any buildup of condensation without allowing any air infiltration. Mechanical drainage of the evaporation trough can be incorporated for applications expected to experience excessive condensation buildup.

The industry leader in skylight technology, Mac Plastics Ltd. has had the Mac Series MSGS Skylight Glazing System fully tested by a certified testing facility. The system yielded superior air in/exfiltration results of 0.32 m3/hr/m of crack length at 75 Pa pressure difference and 0.70 m3/hr/m of crack length at 300 Pa pressure difference. The maximum allowable air leakage as outlined in CAN/CSGBO-63.14-M89 is 2.79 m3/hr/m of crack length at 75 Pa pressure difference. The Mac Series MSGS Skylight Glazing System allows almost nine times less air leakage than this standard. The system also yielded a superior water penetration result of No penetration after 15 minutes of spray at 1000 Pa pressure difference.