The technology built into new windows has advanced significantly over the last twenty years. With QUANTAPANEL IGS, you can add that same technology to your existing windows to obtain near equivalent performance to that of a new window.


The U.S. National Park Service (NPS) calls for the use of exterior or interior storm windows whenever feasible because they are thermally efficient, cost-effective, reversible and allow the retention of the original windows.

The U.S. Secretary of the Interior Standards for Rehabilitation call for preserving windows which are considered to have architectural or historic significance.

The QUANTAPANEL Architectural Low-e Storm Window provides the means to achieve comparable performance to that which would otherwise be specified for new construction, but enables the preservation of the original window, and avoids the problem of irreparable seal failure on insulated glass units (IGUs), a concern expressed by the NPS.

With respect to exterior storm windows, the QUANTAPANEL 500 Series meets the requirements expressed by the NPS in terms of minimal visual impact, and is available in color options that can match the building’s existing trim colors. Should an interior storm product be specified, the QUANTAPANEL 600 Series patented design conforms to the NPS recommendations regarding interior seal performance designed to allow ventilation of the interspace between the panel and prime window to the exterior of the building.


Heating cost reduction of 20% or greater, and cooling cost reduction of 10% or greater can be achieved with installation of the QUANTAPANEL System.

The actual energy savings will vary by building type, the age and condition of the existing windows, the heating & cooling system (fuel), climate and other factors. Energy savings can be substantial and provide the means to achieve a reasonable payback on the investment.

The chart below shows annual and peak load energy savings in a five story, multi-family, building with 40,000 square feet of conditioned space with existing metal-frame single glazed windows in five different metropolitan areas (modeled using natural gas and a 25% window-to-wall ratio). The annual energy savings is the reduction in the building’s annual heating/cooling cost attributed solely to the window retrofit. Peak load reductions (heating and cooling) are shown as well; this is most relevant if the building is considering an upgrade or modification in the existing HVAC system, in which case appropriately sizing the system for a better insulated building may reduce capital cost.

A U.S. DOE funded field study in 2012-13 in two large 3-story apartment buildings with 101 apartments showed that replacing the old leaky clear storm windows over single glazing with the QUANTAPANEL 500 System resulted in: 20% reduced heating energy use, 9% reduced cooling energy use, and 10% reduced overall apartment air leakage (full apartment leakage, not just the window).

Building operating cost improvement can also be realized by reducing the time required to achieve temperature set points after periods of non-use.


Windows can be a major source of unwanted heat loss, and contribute toward discomfort, draftiness, and condensation problems. The advanced technology incorporated into the QUANTAPANEL IGS improves occupant comfort by addressing these issues.

Several factors contribute to the comfort associated with your home or building’s windows. Air infiltration can be a significant source of discomfort, allowing unconditioned air and dirt into or out of your living space.

As well, the interior surface temperature of the glass can be substantially higher or lower than the room temperature during periods when a large temperature differential exists between the interior and exterior of the building. This is particularly problematic during the heating season, when the temperature differential results in an interior glass surface temperature that can be 40 – 50 ℉ below the room temperature. This causes a convection draft at the window’s surface. Another source of discomfort from cold interior glass temperature is a phenomena known as the mean radiant temperature effect. Simply put, the cold surface of the glass has the effect of drawing heat from the warm objects in the room (including the people). The interior glass temperature is also responsible for condensation forming on the interior surface of the windows.

The QUANTAPANEL Architectural Low-e Storm Window reduces air infiltration substantially and provides an insulating effect to raise the interior glass temperature closer to the room temperature. In addition, a reduction in solar heat gain occurs, thus moderately reducing the heat experienced when an occupant is subject to direct sunlight through the window.


Exterior noise can be significantly reduced by installation of the QUANTAPANEL Architectural Low-e Storm Window, leading to a quieter, more comfortable interior environment.

Reducing exterior noise transmission is often a key consideration in residential and commercial buildings, most especially in urban environments. The QUANTAPANEL System has been designed to achieve a substantial reduction in exterior noise transmission through the existing windows.

The chart below shows the attainable reduction, reported in Sound Transmission Class (STC), when installing the QUANTAPANEL 500 (exterior) and 600 Series (interior) in conjunction with a single-glazed and double glazed window. This is based on independent laboratory testing in accordance with ASTM E90 and E413. An STC difference of 10 is equivalent to cutting noise transmission in half. The STC 38-41 achieved by installing the QUANTAPANEL system over single or double pane windows exceeds that, thus reducing noise even further.

While actual field conditions can vary, this provides a good representation of the degree of improvement that can be realized with the QUANTAPANEL System.


The QUANTAPANEL 500 Series, installed on the exterior, provides a layer of protection over the existing window.

A key factor in any building improvement is the resulting impact on maintenance. The QUANTAPANEL 500 Series, installed on the exterior of the existing windows, provides a layer of protection over the existing windows. This acts to preserve and extend the paint life and glazing performance. Homeowners who have original wood windows painted in a color that matches their exterior trim, have found that repainting their existing wood windows followed by installation of the QUANTPANEL 500 Series is a prudent strategy to extend and maintain the life of their original wood windows.


Lower investment cost, lower installation cost, the ability to retain your existing windows, reduce energy cost, reduce maintenance and avoid the future need to replace the windows due to seal failure add up to savings, initially and over the lifetime of the property.

The installed cost of the QUANTAPANEL Architectural Low-e Storm Window is likely to be one-third to one-half the cost of either a wood or vinyl replacement. If considering replacement with an architectural equivalent window, the cost differential can be substantially greater.

The energy savings potential can be substantial, subject to the number, type and condition of the existing windows. In a typical residential building, space heating & cooling costs account for 50% or more of a building’s utility cost. Annual savings can be 20% or more, representing the potential to reduce the annual utility cost by 10% or more. And once the QUANTAPANEL IGS is installed, the energy savings is realized year-round, during both the heating and cooling (unlike seasonal inserts or films).

For historic properties where it is desirable to retain the architecture of the original windows, the QUANTAPANEL provides the means to do so with the added benefit of reduced maintenance and no need to worry about future replacement due to seal failure.