Improved Insulation Properties in Older Windows by Coating with Tightly Packed Aerogel Resin (RFT-590)

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Scientists and engineers at NDSU have developed a coating that can be applied to glass to improve insulation properties by about 80%. The coating consists of a resin containing aerogel particles. Aerogel, a super insulating and durable material, is used by NASA and is widely considered to be the lightest and best insulating product in the world. The team has developed a process for making this resin that allows for extremely tight packing of the aerogel, which makes up nearly 50% of the coating volume. This invention is considered especially useful for improving the energy efficiency of older buildings without the need to remove and replace windows. According to, heat gain and loss through windows is responsible for nearly 25%-30% of residential heating and cooling losses (Reference 1). This newly developed insulation coating can be applied to storm windows, or potentially to applied directly to windows or skylights that are integrated into a building structure. In the lab, we have found that the coating is clear, but slightly cloudy, so may be best suited for skylights and windows that are intended primarily to create natural daylighting.

The table shows that the heat loss/gain through a glass can be substantially reduced by applying the aerogel resin.  This is based on the equation Q = U * A * {Delta}T

heat loss vs gain equation

Where Q is the total amount of heat transferred through a glass, U is thermal conductance, A is area of the glass surface and delta T is the temperature difference between indoor and outdoor temperature. Through application of the new product, the lower modified U factor will provide a major improvement of the building overall heating and cooling loads.


  • Improve energy efficiency of older buildings without needing to replace old windows
  • Resin coats a single pane of glass, rather than needing to be introduced and held between glass panes
  • Greatly reduce condensation on interior glass during cold weather, lessening the potential for water damage on the window frames and sill
  • High visibility, so excellent for “daylighting” situations


Henry Nowak, Technology Manager



RFT, 590, RFT590 

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