With temperatures dipping into the 20s last night, it was absolutely freezing in my house. That’s because my Seattle home is a 1924 Craftsman, with windows that leak air.

insertswindows111Sam Pardue experienced a similar problem with his 1906 Portland Craftsman home, so three years ago he founded Indow Windows. Today, the Portland startup is announcing $1.3 million in funding, led by Vision Ridge Partners of Boulder, Colorado and including participation from the Alliance of Angels, Puget Sound Venture Club, Northwest Energy Angels and Keiretsu Forum. The new cash, which will be used for product development and sales and marketing, caps the series A round at $2.6 million.

Demand was so high for the deal, that the company had to turn down cash. There’s good reason for the interest.

Reuben Munger, managing director of Vision Ridge Partners, notes that there are a billion single-pane windows in the U.S. Many of them are letting the heat escape from the home.

“The company is experiencing strong growth and has put in place the team and infrastructure to scale up rapidly,” said Munger in a release, noting that Indow Windows’ inserts are more affordable and energy efficient than other solutions. (including mine of stuffing a towel by the air leaks).

The inserts, which are made in the U.S. and distributed through 26 dealers, are made of a sheet of acrylic glazing edged with a patented compression tube that allows home owners to easily place inside a window frame. The company says the inserts cost about 80 percent of what it would to replace a window. In addition to boosting energy efficiency, the windows also are designed to reduce noise.

Laser measurement insures a snug fit for the inserts
Laser measurement insures a snug fit for the inserts

An average size window insert costs about $250. The main dealer in Seattle is remodeling company Neil Kelly. They handle the laser measurements of the windows, and then submit the dimensions via specialized software to the company, which custom manufactures each insert at its facility in Portland.

Customers can get a federal tax credit for installing the inserts, and there’s about a 3-week turnaround time from measurement to shipping of the inserts.

Here’s a closer look at how the window inserts are installed.

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  • JimInAuburn

    Why would someone pay 80% the cost of new windows for this? For just a litle more you get a solution that allows you to open your windows and is permanent.

    • jim lewis

      Jim, We live in an old victorian, replacing windows is very expensive, whether is to put in double glass sashes or even complete windows frames. The folks at Indo has a pretty cool solution.

      • Windowless

        But you can’t open your windows :(

        • boop

          But you can take them off in summer right? I *have* observed a good number of Seattleites do have this crazy urge to open windows no matter how cold it is outside.
          If they make them large enough to fit our sliding-glass door (that we never open), we would buy one in a heartbeat.

          • Samuel Pardue

            Hi, Sam Pardue of Indow Windows here. In my house I have 26 windows and 20 of them stay in all year. In the summer I remove some of the Indows at night time and run one fan blowing hot air out a second floor window. Cool air comes in through the other five windows. During the day I shut my windows, pop the Indow inserts back in, and my house stays cool. My house still has plenty of air circulation even with the Indow Windows in, based on the blower door testing we have done.

    • Per-Ola

      Part from the high cost of these panes, I would also question the viability this as moisture can be trapped and condensate between the panes. With enough moisture accumulated, you will create problems inside the wall (starting with the window sill). A home owner really needs to be diligent and remove these panes once in a while to allow it “air out”.
      Older leaky houses are expensive to “run”, but also many times “healthy” from a structural standpoint. Sealing them up properly for energy efficiency is expensive and there are few short cuts.

      • boop

        True. I have known houses that were so airtight they were unhealthy.

        • jim lewis

          Not really an issue. The panes are held in place by a ridge of foam so it is not air tight. I’d be surprised to see much more moisture than we see today. The solution is not for everyone. In our house we have 100 year old single pane glass and pretty large windows. We have had several estimates on replacements. Even the best replacement casement and sash windows would look different and cost a fortune. The folks at Indo Windows thought this thru.

          • Samuel Pardue

            Hi there, Sam Pardue of Indow Windows here. We have found that in almost all cases Indow Windows eliminate or dramatically reduce condensation on windows. If condensation does occur removing the Indow Windows, drying the cavity, and then putting the insert back while making sure they are seated properly almost always eliminates the problem. Also Jim, most people leave many of their Indow Windows in all year. When used with night time ventilation they can keep your house much cooler. See my comment above for more on this. Thanks!

  • Nathan Novak

    Or you just do what we did back in the 80s – buy insulating window film to put on the windows in the winter. Costs a couple bucks per window and does the same thing. http://www.homedepot.com/p/Frost-King-E-O-Indoor-Window-Insulation-Kit-3-Pack-V73-3QPD/100135637#.UpGGa42A34Y

    • Guest

      We do this on our 1910 craftsman house. Take a bit of effort (mostly because our windows are taller then the sheets for there is some extra taping involved) but I have to say it works like a champ and do can barely tell once the plastic is installed.

  • Samuel Pardue

    Hi, Sam Pardue of Indow Windows here. I wanted to clarify one thing about pricing. The Indow Windows typically cost 80% to 50% LESS than replacement windows. An average sized Indow Window will cost about $250 fully installed. Each insert is laser measured and the inserts are custom manufactured with very tight tolerances to be the exact shape of the inside of the window frame, which is important because in our experience 95% of all window frames are significantly out of square. We make 6′ x 4′ parallelograms every day that fit just right! Our dealers do the laser measurement and initial install for our customers to guarantee great quality and a great customer experience.

    • Guest

      I just had estimate provided for regular window 33 inch wide. $300 for each indow window. Looks like it’s cheaper to install a new window. How is it 80% savings?

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