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Indow, known at the time of our investment as Indow Windows, manufactures and sells thermal window inserts that press inside window frames to deliver double pane window performance at a much lower cost. They eliminate cold drafts, reduce heating and cooling costs, and reduce noise transmission by up to 70%.

Indow’s unique laser tailoring system is a particular blessing for owners of older homes whose windows, warped by time and the elements, require a custom solution. Owners can avoid window replacement, which is disruptive, very expensive, and often damages the aesthetics of older homes.

32 million homes in the United States have single pane windows. Homeowners lack an affordable, easy to install, and aesthetically pleasing way to insulate them. The pain is particularly acute for 5.7 million owners of older homes, which tend to have draftier windows that are very difficult and expensive to replace with architecturally authentic looking replacement windows.

Indow’s insert – which utilize no screws, nails or adhesives – deliver double pane window performance at a fraction of the cost of window replacement. They are composed of a sheet of acrylic glazing, edged with patented silicone compression tubing.

Each insert is custom-made to fit a window’s exact shape, even those significantly ‘out of square’, using a proprietary system for precision measuring and manufacturing. Indow window inserts can be customized to just about any shape – rounds, arches, octagons, batwings, odd angles, rounded corners or frames with multiple angles.

The inserts are sold to homeowners through a national dealer network and directly to customers.

Indow has received national accolades for its design. It was selected by Sustainable Industries Magazine as one of the Top 10 Green Products of the Year in 2011 and by Dwell Magazine as one of the Top 10 products at Greenbuild 2012.  The company also won the national Energy Efficiency Award at the CleanTech Open, a Bronze Award in the Energy Efficiency category at the Edison Awards and the 2013 BetterBricks Special Judges Award.

Indow continues to grow its product line, including acoustic, privacy, and sleep panels.  Their promise to customer is that “Indow window inserts boost your comfort, cut your costs and cap your carbon.”

Category: Energy Efficiency, Green Buildings

Based in: Portland, OR

Founded in: 2009

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