Energy Saving Window Features


Revolutionary Performance and Protection.

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How you live is more than how you look. It’s how you perform. How you act and feel, under every condition life can throw your way. We can say this with certainty, because we’ve been around long enough to experience (and help guide) the evolution of window thermal efficiency. And, we’ve taken part in revolutionary ideas in performance and protection along the way. Today, when it comes to thermal efficiency, no other vinyl window manufacturer can match MI’s commitment to producing the highest quality, most thermally efficient windows and doors on the market.



Low “E” glazing system — the lowdown on high performance.

The latest generation in the evolution of MI’s high-performance glazing system options, including proprietary TMAX™ Low “E” and warm-edge technology, keep your home comfortable and energy efficient. The TMAX™ glazing system meets ENERGY STAR® guidelines for energy efficiency in all US climate zones, and these latest advancements deliver optimum performance under the widest possible range of conditions. A combination of an insulating frame and sash, fusion-welded construction, continuous weather stripping, and integral glazing resists air and water infiltration nearly 100% better than the minimum AAMA/WDMA standards.


A detailed system for innovation, quality, and comfort.

detailedTMAX™ is not an isolated innovation. It’s a uniquely designed system that truly gives you the best balance of performance attributes. This is an approach in which every detail counts, and combines:

  • Multi-chambered airspaces and fusion welding in the frame and sashes
  • Double-pane insulating with Low “E” on the inside surface and filled with argon gas Low-conductance material spacer between the two panes

The result is increased insulation value, increased warmth, and decreased condensation.


Performance Standards.

energystar-colorENERGY STAR® Established by the US Department of Energy and the Environmental Protection Agency, the ENERGY STAR® program defines thermal efficiency levels for three different climate regions of the country. The regions are divided by their need for reducing heating costs (northern), reducing cooling costs (southern), or providing the best balance of savings for both (north/central and south/central). Products receive an ENERGY STAR® label for the region or regions for which they qualify. It’s easy to remember that MI windows with the TMAX™ glazing system have qualified for the ENERGY STAR® label in every region.

nfrcLabelNFRC label lets you compare The National Fenestration Rating Council (NFRC) sets standards for reporting energy performance information based on independent testing, so you can compare windows with confidence. In fact, this is the data that the ENERGY STAR® ratings are based on. When you compare, you’ll see that MI windows are among the leaders in thermal efficiency. What’s more, they transmit a high level of visible light for a natural view, and they beat industry standards for air leakage by 100 percent. Learn the measurements that matter:

  • U-value measures heating efficiency This is a window’s ability to block the flow of heat through the glazing system, and retain the heat in the room. The lower the U-value, the better the efficiency. For an easy reference, MI’s proprietary TMAX™ Low “E” glazing system with a low-conductance spacer and argon gas between the panes has a U-value of 0.30, so it is almost twice as efficient as an ordinary double-pane glass system with a rating of 0.50.
  • Solar Heat Gain Coefficient measures cooling efficiency This is a window’s ability to block the infrared heat from the sun, and maintain a cooler temperature in the room. The lower the coefficient, the better. MI’s TMAX™ system has a rating of 0.30, so it is twice as efficient as an ordinary double-pane glass system with a 0.58 rating.


tripplePaneEnergy Saving Options

Maximum Energy Efficiency

  • Foam Filled Mainframe Provides added insulation to the frame.
  • Triple Pane Glass Superior Energy Efficient glass with two layers of LowE and Argon enhancement. The most Energy Efficient MI Window available.


Yearly Energy Savings

yearlysavinigThis illustration shows how much you could save yearly by replacing your old windows. Please visit: for complete energy savings details