Aluminum Storm Windows: Options and Cost

Aluminum storm windows have owned the exterior storm market for seventy years because nothing else matches the combination of thin sightlines, zero-rot frames, and sub-$150 price points. When a client wants to keep original wood windows but stop paying to heat the neighborhood, aluminum storm windows are almost always my first recommendation — the extruded frames weigh a fraction of wood storms, never need paint, and modern versions carry low-e glass that puts real insulation numbers on the table. Here is how to sort through the configurations, finishes, and price tiers before you order.

Why Aluminum Won the Storm Window Market

Wood storm sashes — the kind grandpa hauled up a ladder every October — insulate slightly better, but they need scraping and paint every five to seven years and they weigh 20-plus pounds apiece. Extruded aluminum solved every practical complaint at once. A typical frame extrusion is 0.050 to 0.062 inch thick alloy, strong enough to hold glass in a 40 x 80 opening yet light enough that the whole assembled unit weighs 15 to 25 pounds. The metal will not rot, warp, or feed insects, and a factory-baked enamel finish holds color for decades. Combustibility is zero, which matters in wildfire-zone WUI codes that now restrict vinyl and wood accessories on exteriors. The one genuine weakness is conductivity — aluminum moves heat about 1,000 times faster than wood — but on a storm unit hanging outside the primary window, the trapped air cavity does the insulating, so the frame material penalty is far smaller than it is on a primary window.

Two-Track, Triple-Track, and Fixed Configurations

Configuration determines how you use the window day to day, so choose before comparing prices.

• Triple-track: Two glass sashes and one screen, each in its own channel, all self-storing. Slide the bottom glass up, screen is already there. This is 80 percent of what sells, and the version to buy for any window you actually open. Typical cost: $120 to $250 stock size.
• Two-track: Upper glass fixed in the outer track sharing with a half screen; bottom sash slides in the inner track. About $15 to $30 cheaper per unit and slightly slimmer, but you swap the lower glass for the screen seasonally. Fine for rentals; annoying on a three-story colonial.
• Fixed or picture: One sealed pane, no tracks. Cheapest at $70 to $130, tightest air seal, correct choice over picture windows, attic sashes, and any opening you never operate.
• Basement/utility: Small fixed or slider units around 32 x 15 inches, $40 to $80.

Sliders for horizontal-opening windows exist in two- and three-track versions too; the sashes just travel sideways. Larson, ProVia, and Quaker all build them to order.

Glass Options: Clear, Low-E, and Laminated

Standard fill is 1/8-inch (3 mm) annealed glass, code-upgraded to tempered near doors, within 18 inches of the floor, or in openings bigger than 9 square feet in some jurisdictions — expect a $20 to $40 tempering upcharge per sash. The upgrade worth real money is hard-coat low-e, which reflects room heat back inside and drops the assembly U-factor from roughly 0.50 to near 0.30 over a single-pane primary window. Larson’s low-e line typically adds $30 to $60 per window and pays for itself in three to five heating seasons in climate zones 4 and up. Laminated glass, offered by ProVia and specialty fabricators, sandwiches a plastic interlayer for a 3 to 5 dB additional noise cut and shatter resistance — the pick within a block of a busy arterial. Obscure glass for bathrooms usually costs the same as clear.

Frame Finishes and Colors

Mill finish — raw silver aluminum — is the budget floor, and I steer everyone away from it: it oxidizes to a chalky gray and streaks the siding below within ten years. Baked enamel or powder-coat finishes cost $10 to $25 more per unit and come in white, bronze, sandstone/almond, black, and gray from stocking dealers; ProVia’s custom palette runs 20-plus colors for another $40 to $90. Match the storm frame to the primary window sash color, not the trim — the storm visually reads as part of the window, and a white storm on a bronze-sash house looks like a bandage. Historic districts often require bronze or a custom color and slim sightlines; most commissions accept modern aluminum storms because they are reversible, but get the approval letter first.

Screens: Half, Full, and Mesh Choices

Stock triple-tracks ship with a half screen covering the lower opening, in charcoal fiberglass mesh. Options worth knowing: full-length screens (order at purchase; retrofitting is rarely possible), aluminum wire mesh for pet-clawed first floors at about $10 extra, and fine 20×20 no-see-um mesh in bug-heavy lake country. Solar screens that block 65 to 80 percent of solar gain can be fitted to the screen channel in hot climates and cut west-window heat noticeably, at $25 to $50 per screen. Re-screening later is a $15 DIY with a spline roller, so mesh damage should never scare you off a used or bargain unit.

What Aluminum Storm Windows Cost Installed

Per-opening budget figures from recent jobs:

• Stock fixed unit, mill finish: $70 to $130
• Stock triple-track, white enamel, clear glass: $120 to $200
• Stock triple-track with low-e: $150 to $250
• Custom size, custom color, low-e: $250 to $400
• Oversize or specialty shape: $300 to $600
• Professional installation: $75 to $150 per window; whole-house orders of 12-plus usually negotiate to the low end

A typical 12-window house lands between $2,400 and $4,200 installed with low-e triple-tracks — roughly a quarter of what full replacement windows would run, while keeping the original sashes that give an old house its face.

Installation Notes That Separate Good Jobs From Callbacks

Aluminum storms mount to the blind stops with #8 screws through pre-punched flanges, bedded in sealant on the top and sides only. Three details matter. First, leave the sill flange uncaulked and confirm the weep slots in the bottom rail stay open — sealed weeps trap condensation and rot wood sills faster than having no storm at all. Second, set the sill expander (the adjustable vinyl-swept extrusion at the bottom) so it compresses lightly against the sloped sill; it is the part that actually closes the air path. Third, do not overdrive screws. The frame is light-gauge extrusion, and a bowed jamb channel makes sashes bind on day one. On masonry openings, pre-drill with a 5/32 masonry bit and use Tapcons, with a backer rod and sealant joint instead of relying on the flange alone.

Sizing and Ordering Without Mistakes

Measure the blind-stop opening — the flat wood surround the mounting flange lands on — in three places for width and three for height, and order to the smallest figures; the factory deducts its own clearance. Always state width before height, because 36 x 60 and 60 x 36 are both real windows and custom orders are final. Note the sill slope if it exceeds the standard expander range of about 15 degrees, and count your openings against the sash-split style: storms look best when their meeting rail lines up with the primary window’s check rail, so give the dealer the rail height and pay the few dollars for a custom split on tall windows. Whole-house buyers should measure every opening individually even when they look identical from the lawn — on one 1948 cape I measured last year, twelve “matching” windows came in at five different widths spanning 3/4 inch.

Maintenance and Lifespan

An enameled aluminum storm window is close to zero-maintenance: wash the glass, vacuum the tracks each fall, and hit the channels with dry silicone spray — never oil, which collects grit into grinding paste. Check weep holes annually with a toothpick. Oxidation on older mill-finish frames cleans up with a Scotch-Brite pad and aluminum cleaner, then holds better with a coat of automotive paste wax. Corner keys, sash clips, latches, and glazing splines are all replaceable for under $10 from parts houses like Swisco, which is why 40-year-old units are still in service everywhere. Realistic service life is 30 to 40 years for an enameled unit — meaning the storm you buy this fall is likely the last one that opening will ever need on your watch.