Test Results

Energy star 01 1 - innerglass window systems

Energy Star Certified

We manufacture glass interior storm windows that outperform almost any replacement, yet maintain the integrity and beauty of your historic windows.

Our Compression windows have met all the criteria to achieve Energy Star certification. Click the button below to view our certificate. This means that our Compression windows qualify for the 30% Federal Tax credit under the Inflation Reduction Act, and appropriate rebates under other energy-saving programs.

Scroll down to review the test results that illustrate how well our windows help to insulate against air and sound infiltration.

You’ll also find bid specifications further down the page.

Heat loss slide 1 1 - innerglass window systems

Infrared Proof our Low E glass Storm Windows Save Energy!

Air Infiltration

Test Date & Location:  December 2010 – Brooksby Village Project
Tested By:  Tested by Thompson & Lichtner – Engineering and Testing
Testing Method:  ASTM E 783: Standard Method for Field Measurement of Air Leakage through installed Exterior Windows and Doors.  Air infiltration with 25 mph wind pressure at 1.57 psi
Test standard: .30 cfm/per square foot
Test Result: .04 cfm /per square foot.  7.5 times tighter than the test standard!

Our windows are tighter than almost any
replacement window costing 3 times as much!

Noise Reduction

Tested by Intertek Testing Services in June 1997.  Sound transmission class was determined to be STC 27 based on an ASTM E90-90 Sound transmission loss test.

A further test was done by hermetically sealing around the edges with “Dux-Seal” which only raised it to STC 28, showing that our seals are extremely effective at reducing sound infiltration.

This test qualified us to supply windows to the Boston Central Artery Project for soundproofing around their construction sites.

Bid Specifications

A detailed description of the design and materials used for interior storm windows in a contract.