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Energy Savings

InnerWindows Insulate your Home
InnerWindows = 50% Improvement in Insulation Value

InnerWindows lower the U Factor, or thermal heat transfer, of your windows.  The lower the U Factor number, the greater the insulating value of the window system. U Factor is relevant in both the cold and hot weather. If you touch your existing glass windows on a cold day, the glass will feel cold.  You are paying to continuously to heat that glass surface while it is being bombarded with cold air from the other side.  The surface of the InnerWindow installed with that existing glass window will feel much warmer.  Quite simply, the InnerWindow has created an insulating air pocket between itself and the glass window.  The air pocket keeps the interior surface warm, blocking the cold air and dramatically eliminating the transfer of heat to the outside.  On hot summer days, InnerWindows keep your interior windows cool in much the same way.

In addition, InnerWindows protect your windows from condensation.  In some homes, the warm, moist interior air creates damaging condensation when it contacts the cold window glass, destroying window frames and walls.  InnerWindows eliminates condensation by keeping the window surface warm.

As the chart demonstrates, adding InnerWindows to any single pane glass window dramatically lowers (improves) the U Factor of the window.  In some cases, the U factor is cut in half (insulation value doubled).   KEY FACT:  Adding an InnerWindow to the average single pane glass window will create a window system with a U factor that is BETTER than most vinyl double pane clear glass replacement windows for a fraction of the cost.

InnerWindows Eliminate Drafts

InnerWindows dramatically minimize infiltration of air from around the existing window.  This draftiness can actually be a larger source of lost energy and home discomfort than U Factor.  Air leaking in is air that now needs to be heated (or cooled).  Often times this drafty feeling causes people to turn up the thermostat in an attempt to be comfortable.  The house is now warmer (and more expensive to heat) but the people are just as uncomfortable.

Inner windows eliminated drafts

We have tested the effectiveness of Capitol InnerWindows by hiring an independent energy auditor to conduct Blower Door Tests on a home in which we have installed InnerWindows.   The Blower Door Test uses sophisticated technology to de-pressurize the home and calculate air infiltration.  With InnerWindows in place, air infiltration via the windows is virtually eliminated!  The physical area of the gaps closed by the Climate Seal Inner Windows was equivalent to a 12” by 18” window open ALL THE TIME.  That translates into a much more comfortable home.

Capiltol inner window blower door test

How much will you SAVE?

Projecting payback time and future energy savings of any window replacement/ improvement requires examining multiple factors.  Exact numbers can be obtained by hiring an independent energy auditor who will inspect the condition of your current windows and perform a blower door analysis.  We can recommend several good auditors in your area.

However, we have done extensive analysis of test homes in the Richmond area that have been tested Before and After to determine the real test results.  These tests were conducted by an Independent Energy Auditor.

Click Here to Download a Copy of the Report

The home contained 21 single pane wood frame windows.  The Auditor estimated the savings to be $162.90 due to the upgraded U-Value and $160.00 in savings due to reduced air infiltration.  The total projected annual savings for this home was 322.90 per year.  Given that most InnerWindows cost between $200 and $250 per window, the actual total cost for this project was $4746.  The calculated payback time is $4746/$322.90 or 14.69 years.  15 years is short compared to widely published industry data that shows that the average payback for replacement windows is more than 40 years while the expected lifetime is only 20 years.  We are so sure that ClimateSeal installed by Capitol Inner Window will be the FASTEST PAYBACK that we back it with a written GUARANTY.

The InnerWindows will pay for themselves in 15 years while the home owner enjoys the advantages of a more comfortable home due to less street noise, reduced drafts, and enjoys the fact that the exterior of their home is not changed at all.

Fastest Payback Guaranty

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Blower test results