Energy-Efficient Storm Windows

Understand the role of Low-E glass, air sealing, and fit when improving the comfort of your existing windows.

Address drafts and heat transfer together

An added panel creates an air space alongside your existing glass. A close fit helps limit drafts, while the glazing affects heat transfer. Before buying, inspect the primary window and its surrounding frame: a new panel cannot correct water entry or structural damage.

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Understand what Low-E adds

Low-emissivity, or Low-E, coatings reduce radiant heat transfer through glass. They offer a different function from tint or a screen. The best choice depends on the existing window, climate, sun exposure, and the glazing options offered for the selected system.

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Choose a mounting system that fits

Compare interior and exterior mounting before choosing glazing. Check the space available for the frame and the clearance needed for operating hardware. Proper installation and maintained weatherseals matter alongside the glass selection.

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Set realistic expectations for savings

Energy results vary with climate, existing windows, air leakage, installation, and heating and cooling use. Do not treat a general savings estimate as a guaranteed reduction in your bill. Compare product-specific performance information when available; Low-E glass alone does not establish ENERGY STAR certification.

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Inspect the existing window before upgrading

Look for loose or missing weatherstripping, gaps around the sash, damaged glazing, and signs of water entry. Note whether the discomfort is a draft around the edge or a cold sensation near the glass. Those observations help distinguish air leakage from heat transfer. Repairs to the primary window may be needed alongside a storm panel, particularly where the surround is too damaged to support a secure attachment.

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Keep the installed system performing

After installation, check that operating panels close fully and that seals meet evenly. Inspect exterior drainage openings and keep them clear. If condensation persists, investigate moisture sources and the installation rather than simply sealing every visible opening. During seasonal cleaning, check loose hardware and damaged seals so the system continues to fit as intended.

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Vertical storm windows

Explore an operating exterior option for tall openings. Confirm track layout and mounting details for your existing sash.

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Horizontal sliders

Compare side-sliding operation for wide openings, with size and finish choices on the product page.

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Interior compression fit

Explore a room-side panel for an opening with suitable mounting depth and clearance.

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FAQs

Do Storm Windows Help Reduce Drafts?+

A properly fitted storm window can help reduce air leakage around an existing window. Results depend on the mounting system, weatherseals, and condition of the primary window.

Is Low-E the Same as Double Glazing?+

No. Low-E describes a coating that reduces radiant heat transfer. Double glazing describes an insulated glass unit with two panes. A Low-E storm panel is a separate addition to your existing window.

Are All Storm Windows Energy Star Certified?+

No. Certification applies to specific products meeting program requirements. Do not assume certification from the words storm window or Low-E.

Will I Save a Fixed Percentage on Energy Bills?+

No single percentage applies to every home. Existing window performance, climate, installation, and household energy use all affect the result.

Do Storm Windows Help Insulate?+

Yes. The added panel and air space help slow heat transfer, and a well-fitted system can reduce drafts. Low-E glazing also reduces radiant heat transfer. The improvement depends on the existing window and the installation.

Find the right storm window for your home.

Choose your style, then configure the size and options for each opening.