| Aluminum Storm Windows

Model Selection Note: Storm window type should be selected based on the existing window operation, desired ventilation, screen location, mounting style, and field conditions. Storm windows are secondary exterior windows and are not intended to perform like rated primary replacement windows.

Arched top two-track double-hung storm windows and arched top picture storm windows are expected to be available starting in July/August 2026 for select applications.

These models may be useful for historic homes, architectural openings, churches, schools, municipal buildings, multifamily properties, and other projects where the existing opening includes an arched top condition. Availability, sizing, frame style, glass options, and final order requirements should be reviewed during quoting.

• Maximum size varies by model and configuration.
• Storm windows are custom-sized to fit specific existing openings.
• Blind stop and overlap mounting availability may vary by model.
• Picture storm windows are not available with an overlap frame.
• Screen type, glass type, frame style, sill expander selection, and hardware upgrades should be reviewed before ordering.
• Storm windows are secondary exterior windows and are not intended to perform like rated primary replacement windows.

For additional dimensional information, review the Dimensions & Specs section or download the Storm Window Brochure.

Color Note: Digital color swatches can vary by screen, lighting, and device settings. Actual painted aluminum colors should be confirmed with physical samples before final color selection whenever color match is critical.

• Actual colors may vary from digital swatches.
• Physical color samples should be reviewed before final selection when color accuracy is important.
• Clear anodize and mill finish options may also be available depending on the project.
• Custom color options may be reviewed when standard or Estate Colors do not meet project requirements.
• Color selection should be reviewed with the storm window type, project requirements, and existing exterior conditions before ordering.
• Storm window colors can also be coordinated with Casco Aluminum Storm Doors and the Casco Aluminum Porch Enclosure System when a consistent exterior storm protection package is desired.

Selection Note: Available glass and screen options may vary by storm window type and project requirements. Picture storm windows do not include a screen by default, but a removable screen insert or a screen rolled into the master frame may be available when specified.

Safety Glass

Tempered safety glass and plexiglass are available in place of standard annealed glass where required or preferred.

• Tempered safety glass may be required by code or project conditions depending on the application.
• Picture storm windows over 15 square feet require tempered glass.
• Plexiglass is available as an alternative to glass where a lightweight or impact-resistant glazing option is desired.

Obscure and tinted glass options are often used in bathrooms, mud rooms, utility areas, sidelites, basement openings, and other applications where privacy, reduced visibility, or a specific appearance is desired while still allowing light into the space.

Available specialty glass options may vary by project requirements and should be reviewed before ordering.

• LoE i89 is the available Low-E glass option for Casco storm windows.
• Tempered glass may be required depending on size, location, code, or project requirements.
• Picture storm windows over 15 square feet require tempered glass.
• Standard fiberglass mesh screen is used for common screen applications.
• BetterVue is commonly selected when clearer views and upgraded screen performance are desired.
• PetScreen is commonly selected when added screen durability is needed.
• Picture storm windows do not include a screen by default, but screen options are available when specified.
• Glass and screen options should be reviewed with the selected storm window model before ordering.

Hardware Note: Hardware availability and upgrade details may vary by storm window type. Double-hung, picture, and slider storm windows may use different hardware combinations because of how each window operates.

• PVC hardware and corner keys are standard on Casco storm windows.
• Die cast metal hardware is available as an optional upgrade where applicable.
• Slider storm windows use metal latches only with PVC corner keys when the metal hardware upgrade is selected.
• Frame stabilizer bars may be included by default on larger windows.
• Hardware selection should be reviewed with the storm window type, size, and project requirements before ordering.

Quick Measuring Note: Measure carefully, use the smallest opening measurement, and confirm whether the order is being submitted by opening size or exact tip-to-tip frame size. If a sill expander is selected, Casco will make the needed adjustment to include the expander in the final overall storm window dimensions unless unusual project conditions require otherwise.

Helpful Storm Window Resources

Sill Expander Dimension Chart | Storm Window Brochure | Storm Product Warranty | Quick Installation Overview Video

Note: If the storm window includes a sill expander, Casco will make the necessary adjustments to incorporate the expander into the final overall window dimensions. Customers should not compensate for the expander unless unusual project conditions require it.

What is sightline? Sightline is the measurement from the outer tip of the installation flange to the edge of the visible glass. It shows how much of the storm window frame is visible around the glass.

Expander Note: Sill dimensions shown above do not include the sill expander. The 7/8" sill expander adds 7/8" to the visible frame width at the sill. The 1-1/2" sill expander adds 1-1/2" to the visible frame width at the sill.

The frame, flange, and visible frame width dimensions shown above are rounded to common fractional dimensions for reference only. Exact production dimensions may vary slightly.

Downloadable Resources

Use these documents to review Casco storm window models, features, available options, sill expander dimensions, and warranty information.

American Storm Window Manufacturing Since 1960

Since 1960, Casco has built window, door, and storm solutions with real manufacturing experience behind them. We extrude, paint, fabricate, and assemble our aluminum storm products at our South Elgin complex, supported by a physical factory, showroom, dealer network, and people who can help after delivery.

Our Story  |  Contact, Showroom & Factory Address  |  Product Resources

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Storm windows are exterior windows installed over an existing primary window. They add a second layer of protection and create an insulating air pocket between the original window and the storm window.

That air pocket is the key benefit. Similar to insulating glass, where performance comes from the space between panes, a storm window helps improve comfort by creating a controlled space between the existing window and the outside weather.

Casco Aluminum Storm Windows are manufactured at our South Elgin, Illinois complex. We manufacture the aluminum extrusions on-site, then paint, fabricate, and assemble each custom unit within the same complex.

With approximately one million square feet of manufacturing and operational space across South Elgin and Genoa, Casco maintains direct control over product fit, finish, customization, consistency, and quality. Learn more about our manufacturing capabilities or view our factory, showroom, and contact information.

Storm windows preserve a sound, repairable primary window while adding comfort, protection, and less disruption than full replacement. Replacement may be more appropriate when the existing frame or sash is severely rotted, damaged, unsafe, or no longer functional.

When the opening can remain but the operating components need improvement, also review Casco’s Aluminum-Clad Double-Hung Replacement Kit and Aluminum-Clad Replacement Casement Sashes.

No. Casco storm windows should not be represented as security, hurricane, or impact-rated products unless project-specific Casco documentation says otherwise. Tempered glass and plexiglass options do not create a tested impact-rated window system.

Use the Storm Window Brochure, Sill Expander Dimension Chart, Measuring and Installation Video, or the full Casco Resources page.

Storm windows create an insulating air space over the existing window, reducing air movement and improving comfort. A properly fitted unit can help older windows feel less drafty, while LoE i89 glass may provide additional performance.

A Pacific Northwest National Laboratory report prepared for the U.S. Department of Energy found average source heating and cooling energy savings of 21% to 36% for low-e storm windows and panels over single-pane windows in colder and mixed climates. Results vary, so Casco does not guarantee a fixed savings percentage.

The added layer may also reduce some perceived outside noise, but Casco storm windows are not acoustically rated or soundproof.

No. Storm windows are secondary exterior windows, not rated primary windows. They reduce drafts and weather exposure but must allow incidental moisture or condensation to drain through the frame.

Correct measuring, installation, weep openings, and sill conditions are essential. Review Casco mounting, measuring, and sill information.

Yes. Casco Aluminum Storm Windows are built to the nearest 1/8" for existing openings that may not match standard sizes. Review available models and size limits.

Identify the blind stop or overlap frame style. Using a rigid metal tape, measure width at the top, middle, and bottom and height at the left, center, and right; record the smallest of each to the nearest 1/8". Label every opening and work from a safe position.

State whether dimensions are opening size or exact tip-to-tip size. Tip-to-tip is the finished outside frame dimension, including the compressed sill expander in the height when selected. Standard calculations are blind stop: opening width and height minus 1/8"; overlap: opening width plus 1" and height plus 1/2". Do not substitute generic online rounding rules.

Review Dimensions & Specs and the measuring and installation video before ordering.

Yes, when alignment matters. Record the existing primary window’s glass and meeting-rail locations and identify any requested custom meeting-rail or mullion position when the selected Casco model allows it. This helps the storm window sightlines coordinate with the window behind it. Three-track models do not offer custom meeting-rail locations.

Limits vary by model: double-hung models up to 54" x 88"; two- and three-track sliders up to 88" x 60"; double-end sliders up to 100" x 60"; and single picture or basement units up to 50-1/2" x 93-1/2" or 93-1/2" x 50-1/2". Larger fixed units may be possible with a mullion.

Picture windows over 15 square feet require tempered glass. Review unusual or code-sensitive applications and current model limits during quoting.

Arched-top two-track double-hung and picture storm windows are expected beginning July/August 2026. Confirm launch status, sizing, frame style, and glass options during quoting.

Picture storm windows serve fixed openings, sidelites, and basement windows where ventilation is not required. They include a removable exterior glass panel for cleaning. Clear annealed glass is standard; a removable screen or screen rolled into the master frame may be specified.

Both use two glass panels and a half screen. A two-track double-hung places the half screen in the lower exterior track; a three-track gives the screen its own track so it operates independently and vents from the bottom. Track count describes panel arrangement, not a guaranteed performance advantage.

An oriel model uses unequal glass-panel proportions to align with cottage-style or oriel primary windows. Record meeting-rail locations when alignment matters.

Compare Casco double-hung storm window models, maximum sizes, and screen locations.

On a Casco two-track slider, only one of the two sash panels is active, so handing must be selected when ordering. It includes a half screen on the exterior track. On a three-track slider, both panels can slide in either direction and two half screens form a full screen system that can be removed from the interior. Review Casco slider and double-end slider models.

Use double-hung models over vertical windows, slider models over horizontal openings, and picture or basement models for fixed openings. Casco’s listed configurations include two-track, oriel, and three-track double-hung; two-track, three-track, and double-end sliders; and picture, sidelite, and basement units.

Also consider screen location, operation, mounting style, depth, sightlines, and drainage. Compare the models Casco offers.

A blind stop frame installs inside the recessed blind stop area when adequate depth is available. An overlap frame mounts over the face of the exterior casing, brickmold, trim, or opening. Overlap is available on most models, but not picture storm windows.

Choose based on opening depth, trim, frame condition, drainage, and appearance. For larger seasonal enclosures, also review Porch and Patio Solutions.

Review the Casco blind stop, overlap, flange, frame-depth, and sightline details before measuring.

Most install from the exterior. The model, frame style, trim, opening condition, and access determine the method. See the installation overview video.

An experienced homeowner may install a straightforward, safely accessible unit. Large or heavy windows, upper stories, deteriorated frames, and unusual conditions should be handled by a qualified installer.

Before installing, confirm the model and handing, size and frame style, glass and screen, color, sill expander, and hardware. Repair rot, loose material, obstructions, or drainage problems first.

An installation screw pack and pre-punched mounting holes are available when specified. Confirm both on the order because included components vary.

No. Perimeter sealing must preserve the bottom drainage path and weep openings. Never trap water between the primary and storm windows; use a qualified installer when the proper approach is unclear.

A sill expander closes the lower gap at a sloped, uneven, worn, or out-of-square sill while supporting a finished appearance and drainage. Casco offers color-matched 7/8" and 1-1/2" options: use 7/8" for minor adjustment and 1-1/2" when greater coverage is needed.

When ordering by opening size, do not compensate for the expander unless Casco identifies an unusual condition. Select and install it so water can shed without becoming trapped. Review the Expander Dimension Chart and Dimensions & Specs.

Standard construction includes heavy-duty extruded aluminum averaging .063" wall thickness, clear annealed glass, frame weather-stripping, and an integrated mounting fin. Sill expanders and other components vary by model and order.

See the Storm Window Features section and Casco Storm Window Brochure for a current product overview.

Use clean water, mild soap, and a soft cloth or non-abrasive sponge. Clean removable screens gently and let them dry before reinstalling. Avoid abrasive pads, scrapers, and harsh solvents; follow specialty glass or screen care instructions.

Periodically clear tracks and drainage openings, inspect weather-stripping and screen fabric, check screws and hardware, and test panel movement. Also watch the primary window, trim, and sill for deterioration or trapped water.

Binding panels: Check for dirt, paint, sealant, bent material, incorrect track placement, an out-of-square frame, or over-tightened fasteners. Do not force the panel.

Drafts: Check perimeter fit, weather-stripping, panel position, fasteners, and the primary window. Keep bottom drainage open.

Condensation: Warm humid air contacting a cold surface is common. Close and reasonably seal the primary window, manage indoor humidity, and clear storm-window drainage. Persistent moisture, staining, or wood deterioration should be evaluated.

Normally, no. Operable models provide ventilation through their glass-and-screen arrangement. If a panel is removed for cleaning or service, label it by opening, protect it, store it upright and dry, and return it to the correct track.

Request help for incorrect sizing, damaged or out-of-square frames, cracked glass, broken or missing hardware, unsafe panel operation, unresolved drainage, rot, or structural deterioration. Provide the production order number, opening location, photos, and a description. Start with the supplying dealer or installer, or contact Casco.

Options include clear annealed glass, LoE i89, obscure glass, tempered safety glass, tinted glass, and plexiglass. LoE i89 can reduce heat transfer while maintaining a clear appearance; actual performance depends on the complete opening and installation.

Tempered glass may be required by application or code and is required on picture storm windows over 15 square feet. Do not claim a UV-reduction percentage without current data for the exact glass selected. Compare glass and screen options.

Operable models include screens according to their configuration. Picture storm windows do not include one by default but may be ordered with a screen rolled into the master frame or a separate removable insert.

Fabric choices include standard vinyl-coated fiberglass, clearer-view BetterVue, and more tear-resistant PetScreen. Availability varies by model. Compare screen options.

They add an exterior frame, but custom sizing, frame styles, colors, and careful field finishing can help preserve a building’s appearance.

Options include eight standard painted colors, clear anodize, mill finish, Estate Colors, and custom colors. View available colors and use a physical aluminum sample for critical matches.

Generally, yes. The primary window remains, but fastener holes, sealant, paint lines, or trim touch-up may still be visible after removal.

Standard PVC hardware and corner keys are included. Optional die-cast metal hardware adds durability where available, and some larger configurations use frame stabilizer bars. Review Storm Window Hardware.

Related options include Casco Aluminum Storm Doors, Porch Enclosure Systems, Sliding Patio Screen Doors and Frame Kits, and Retractable Screens.

Yes. Custom sizing, frame styles, and colors can preserve the appearance of original wood windows while adding comfort and exterior protection. Storm windows are often installed after repair, reglazing, or repainting to help protect that investment.

Review Historic Home Solutions. Casco’s Double-Hung Replacement Kits may also be paired with storm windows.

Wood windows are a common application. Casco does not recommend installation over vinyl windows because heat buildup may contribute to fatigue or distortion. Review other materials and unusual conditions before ordering.

Individual framed openings may accept fixed or operable storm windows. For larger conversions, review Casco’s Porch Enclosure System. Neither product automatically creates code-compliant year-round living space; structure, insulation, utilities, egress, permits, and local codes remain separate.

Yes. Picture and basement models serve fixed openings, but must not obstruct required egress, ventilation, or drainage. A storm window is not foundation or window-well waterproofing.

Separate units may be considered for individual framed openings when each can be measured, fastened, operated, and drained correctly. Casco does not offer a single engineered multi-panel bay or bow storm-window system.

Casco storm windows are available only in the shapes and configurations specifically listed in the Storm Window Models section. Custom-sized does not mean custom-shaped. Any shape that is not specifically listed as available is not offered.

A listed Casco model may be used in a suitable framed opening with secure mounting and drainage. Review exposure, ventilation, condensation, temperature, safety glazing, and code requirements. Storm windows are not structural greenhouse panels, livestock systems, emergency components, or rated industrial products.

Do not assume coastal, hurricane, impact, design-pressure, corrosion, or high-wind compliance. Rated projects require written documentation for the exact configuration before ordering.

Yes. Casco Aluminum Storm Windows can improve comfort and protection across multifamily, school, historic, municipal, and other repeated-opening projects without the interior demolition of full replacement. Exterior installation can also reduce disruption in occupied buildings.

Projects may be completed in phases. Establish consistent frame, color, glass, screen, and installation specifications at the start so later phases maintain a coordinated appearance.

Yes. Architects can select from defined frame styles, colors, glass, and screens to support historic, institutional, multifamily, and light-commercial work. Product selection and field detailing can preserve the intended appearance without redesigning the storm window itself. Review Architect-Specified Windows & Doors.

It may be available, especially for repeated sizes and consistent frame, color, glass, and screen specifications. Provide quantities, sizes, options, installation conditions, and phasing plans to the supplying dealer or Casco for review.

Yes. Contractors, remodelers, glaziers, restoration professionals, and window-repair companies use Casco storm windows when an existing window remains serviceable or worth preserving. Review solutions for glazing contractors.

Yes. Casco supplies dealers, lumberyards, building-material suppliers, and wholesale distributors serving homeowners, contractors, property managers, and architects. Consistent demand may also support a stocking program. Start a Casco dealer inquiry.

Related dealer categories include Storm Doors, Porch Enclosure Systems, Double-Hung Replacement Kits, Replacement Casement Sashes, and Sliding Screen Door Kits.

Yes. A qualified dealer, lumberyard, contractor, or supplier can coordinate Casco products with project conditions. Provide model, frame, color, glass, screen, quantities, and installation details early.

Yes. Most sales go through local dealers, but Casco can review national supply and special arrangements where local support is unavailable. Direct delivery or LTL freight depends on product, quantity, packaging, destination, access, and unloading conditions. Contact Casco to review the project.

Review the current Casco Storm Product Warranty. The written document contains the complete terms and controls.

Start with the supplying dealer, lumberyard, contractor, or installer. For general support, use Casco Resources or contact Casco. Include the order number, product, opening location, measurements, and photos.

Yes. Casco offers a wall-mounted dealer display with removable storm-window, storm-door, and porch-enclosure samples for showroom or field demonstrations.

It includes a backboard, blind-stop/overlap graphic, standard color samples, hardware, instructions, 25 pieces of literature for each product category, and these removable samples:

Storm windows: Two-Track Double Hung Blind Stop, Three-Track Double Hung Blind Stop, Two-Track Slider Blind Stop, Three-Track Slider Blind Stop, and Picture Storm Window.

Storm doors: Full View, Full View with Kick Plate, Self-Storing, and Screen Door.

Porch enclosure: F-Channel system with glass and screen inserts.

Order through CASCOPRO or return the display form to the assigned customer service representative. The display is 24" wide x 80" high x 24" deep and must be securely wall-anchored because the samples swing.