Glass Options

Get the most out of your windows with ENERGY STAR® rated glass




Harvey gives you the flexibility to choose the performance package that fits your project with several
glass options that meet ENERGY STAR requirements as well as additional energy efficient packages.



ThermaLock 3X

ThermaLock 3X with roomside Low-E is our premium ENERGY STAR option. It kicks performance up a notch with three Low-E coated panes of glass, making it the best choice to significantly reduce energy consumption in climates where both cooling and heating costs are a concern. 


How ThermaLock 3X Works 

  1. A special coating, known as Low-E, is applied to the glass to reduce temperature transference by reflecting infrared light. Low-E is a non-toxic, environmentally friendly way to enhance a window’s energy efficiency. 

    Low-E coatings can be applied to the various sides of the glass panes. Our highest performing glass packages feature a roomside Low-E coating, found on the inner most glass side. ThermaLock 3X utilizes two additional layers of Low-E applied to the other glass panes.

  2. Colorless, odorless, non-toxic Argon gas fills the space between the glass. Because it’s heavier than air, it provides superior insulation than air alone, increasing the thermal performance of the glass.

  3. The areas where the edges of the glass meet the frame are most vulnerable to temperature transference, so a warm edge spacer is used to insulate where the glass seals to the window frame, reducing heat transfer through the window.



Best for Northern Climates

SunGain Plus with roomside Low-E, is engineered to have a high Solar Heat Gain Coefficient so more of the sun’s rays penetrate the glass to offset heating, providing superior performance in northern climates.

SunGain Plus also has our highest Visible Transmittance (VT) rating which means it allows more natural sunlight in.

ThermaLock RS

Best for North-Central Climates

ThermaLock RS with roomside Low-E helps to keep interior temperatures consistent by reflecting heated or cooled air back inside, while still allowing ample sunlight in.


Best for South and South-Central Climates

SunShield Plus with roomside Low-E and SunShield work by shielding the home from solar heat and ultraviolet rays that can fade furniture and carpet.

Tinting is minimal with virtually no exterior reflectance, keeping the view unobstructed.