At Efficient IGU we aim to provide the type of unit that is best suited to your requirements
to this end we provide you with a comparison chart for your information to down load.
Below is an explanation of the performance data
Daylight - is the products visible light transmission as a percentage.
Solar - is the solar heat gain coefficient (SHGC). The lower the number, the better
Insulation - is the products U Value. The lower the number the better performance.
High performance tones
IGU + Low E
Viridian SuperGreen™ has the highest light transmission & Virdian SuperGrey™ has
the lowest of the high performance tones
Viridian SuperGrey™ has the highest solar performance. Its SHGC of only 0.35 eliminates
the most solar heat
With all the high performance tones Low E™ has the best insulation. Note the solar
control is also increased with very little loss of day light
EXPLANATION OF PERFORMANCE DATA
The following chart is an extract from the performance data table. The information
is for the standard stock items in Efficient IGU range. Not all manufactured or custom
options have been included
Note: Data is based on laboratory spectrophotometric measurements and reduced using
Windows software for NFRC 100-2001 conditions, which is the internationally recognised
method for describing glass performance. The data is glass only and care should
be exercised when evaluating manufacturer’s published data when the same environmental
conditions have been used.
Product name - refer to product for more information where (#2) appears, this identifies
the glass coated surface that is glazed to the inside of a building or the inside
of a Double Glazed unit.
Nominal thickness - the glass thickness or the make-up of a Double Glazed Unit. The
first number is the outer glass thickness +12mm gap (spacer), then the thickness
of the inner panel of the unit. Thickness tolerances are:
Visible light transmission - percentage of visible light passing directly through
the glass. The wave length range of visible light is 380 to 780nm. The higher the
percentage the more daylight.
Visible light reflection - percentage of visible light reflected toward the exterior
Solar transmission - percentage of normally incident visible light and solar energy
passing directly through the glazing. The wave lengths measured for solar energy
is 300 to 2500nm.
Solar reflection - percentage of normally incident visible light and solar energy
reflected toward the exterior
UV transmission - the percentage of UV light transmitted measured in the light range
of 300-380nm. The lower the number the better.
U Value - measurement unit is watts per mper degree celcius (W/m°C) and is a measure
of the rate of heat gain or loss through glazing due to environmental differences
between outdoor and indoor air.
Shading coefficient - the ratio of solar heat gain through the glass relative to
that through 3mm clear glass. The lower the number the better the performance.
SHGC (Solar Heat Gain Coefficient) - the proportion of total solar radiation that
is transferred through the glass at normal incidence. It comprises the direct solar
transmission (5) and the the part of the solar absorption dissipated inwards by radiation
and convection. The lower the number the better the solar performance