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Technology: Building Envelope

Window Energy Management Systems (WEMS™) units

Mackinac™ WEMS™ units transform windows from a primary source of energy loss into a contributor to the energy needs of a building.

WEMS™ units are easily installed over glass windows to significantly enhance window energy performance.

Advanced Polymer Films
Architectural-grade polymer films with high clarity are tough, non-yellowing, puncture resistant, and non-flammable.

Low-E / Anti-Reflective Coating
The Mackinac™ low-e coating reflects ultraviolet and infrared heat energy, is clear and antireflective to visible light.

Light and Thin Structural Framing
Our light-weight, corrosion-resistant structures enable us to make units with narrow frames that can be color matched to fit the aesthetic features of any décor.

With added dynamic shading, WEMS™ units can provide control of solar heat gain.

WEMS™ performance

Thermal Insulation

WEMS™ units increase the thermal insulation performance of glass windows. A double-pane unit will add R-5 to an existing glass window.

Solar Heat Gain

With added dynamic shading, WEMS™ units can provide control of solar heat gain with values ranging from SHGC 0.10 to 0.65.


The coated polymer films for WEMS™ units are highly transparent to visible light. A double-pane WEMS™ unit will transmit more than 85% of visible light.

Glare Control

Light reflecting louver systems can be added to manage glare and provide redirection of visible light for optimal daylighting performance.


WEMS™ units increase comfort. They eliminate the chill felt from sitting by cold windows in winter and the excessive heat from hot sun in summer. Optional shading systems will also reduce glare, solar heat gain, and provide privacy.

WEMS™ installation is easy

Heat pumps and electric vehicles encourage the transition to renewable energy sources, but electrification increases strain on the grid.

Installed in a fully electrified house, our technology will offset the power demand of two electric cars.