Best Acrylic Window Replacement Panels (2026)

A broken pane in a shed, a garage door, a porch enclosure, or a storm door is the most common reason anyone buys a piece of acrylic. Glass in those places breaks from a thrown ball, a mower stone, or a slammed door, and acrylic does not: about 17 times the impact resistance of plate glass at half the weight, 92 percent light transmission, and no yellowing. It is cheaper than tempered glass, you can cut it yourself if you have to, and a garage door opener lifts it more easily than the glass it replaces.

There is no single "replacement panel" product. What you buy is sheet cut to your opening, and the decisions are the supplier, the thickness, cast or extruded, and how you fasten it. This guide covers all four.

Our picks at a glance

How thick?

Thickness is set by the size of the opening and the wind it sees, not by the thickness of the glass you are replacing. ACRYLITE's glazing guidance at a 30-pound-per-square-foot design load, which covers most windows under 30 feet above ground, gives these anchors:

ShapesPlastics' rule of thumb agrees: 1/8-inch acrylic for indoor windows, greenhouses, sheds, and screened porches; 3/16 for larger windows, porches, garages, and barns; and polycarbonate at 1/4 inch for workshops and vandal-prone spots or 3/8 for hurricane zones. Acrylic needs 1.5 to 2.5 times the thickness of glass for the same stiffness, so if the old glass was 1/8, the acrylic should be 3/16 or 1/4 in anything but a small pane.

A quick screening formula from the glazing trade: thickness of at least the span divided by 200. A 40-inch pane wants about 0.2 inch, so 1/4.

Cast or extruded?

Extruded is cheaper, roughly $3 to $6 per square foot at 1/4 inch, and fine for a flat pane in a frame. Cast costs about 20 percent more, has better clarity, chips less on the saw, and holds up better in decades of sun. For a shed or garage, extruded. For a porch, sunroom, or storm door pane you look through every day, cast. Our plexiglass vs acrylic explainer covers why they differ.

1. Acme Plastics Cut-to-Size Acrylic

Best Overall. Acme shows you the price before you commit. Choose the material and thickness, enter the pane dimensions, and the site prices the piece on the spot. A stock 1/4-inch 24-by-48 clear extruded sheet was $41.52 on sale against $55.37 regular, about $5 a square foot, and custom sizes scale from there. Free freight is available on qualifying orders, and 3-packs of common sizes are stocked for a multi-pane job like a porch.

For a replacement pane that is the whole story: the right size, cut square, at a known price, delivered. The sheet is house-stocked rather than a named brand, which does not matter for a shed window.

Price a pane at Acme Plastics

2. ShapesPlastics Replacement Windows

Best for Porches and Barns. ShapesPlastics has a page built for exactly this job, with a thickness-by-use table that tells a homeowner what to order without a phone call: 1/8-inch acrylic for indoor windows, greenhouses, sheds, and screened porches; 3/16 for larger windows, porches, garages, and barns; and 1/4 or 3/8-inch polycarbonate for workshops, vandal-prone areas, and storm zones. Cutting is to plus or minus 1/8 inch, orders ship in 24 to 48 hours, and a cost calculator prices the piece.

Having polycarbonate on the same page matters. A shed window a ball hits every week should be polycarbonate; a porch pane the sun hits every day should be acrylic. Our acrylic vs polycarbonate guide draws the line.

Shop ShapesPlastics replacement windows

3. Freckleface Garage Door Windows

Best for Garage Doors. Garage door window panes are small, numerous, and set in a snap-in or screw-on frame that is particular about thickness. Freckleface has specialized in them for years, with acrylic from 1/8 to 1 1/4 inches and polycarbonate from 1/8 to 1/2, cut to the dimensions you enter in the cart. The company is upfront that it does not carry model-specific replacements for Clopay, CHI, Sears, or the big-box doors; you measure the old pane and they cut to match. The weight saving over the original glass reduces strain on the opener, which is a real benefit on an older door.

Freckleface garage door window replacement

4. OPTIX Acrylic Sheet at The Home Depot

Best Same-Day. Plaskolite's OPTIX is the extruded sheet on the rack at Home Depot, in stock sizes from small panes under $9 to full sheets around $535, and many stores will cut it. For one broken shed pane on a Saturday, it is the answer. It is extruded, so it chips if you rush the cut and scratches more easily than cast; the edges will be saw-cut, not polished; and the thickest common stock is 1/4 inch. Right for the shed, wrong for the sunroom.

OPTIX 1/8-inch acrylic at The Home Depot

5. ACRYLITE Cast Sheet via ePlastics

Best for Panes That Will Last Decades. For a porch enclosure, a sunroom, or a storm door where you will look through the pane every day for twenty years, buy cast. ePlastics stocks ACRYLITE and Plexiglas G cast sheet from 0.060 inch to 4 inches, cuts it on CNC saws and routers, and polishes edges and drills holes as line items. Cast sheet's clarity, chip resistance, and long-term weathering are what you are paying for, and a polished edge in a wood frame looks like glass. Our suppliers roundup compares ePlastics with the rest of the trade.

Shop cast acrylic at ePlastics

How to fit the panel so it lasts

Acrylic replacement panes fail for one reason: they were installed like glass. Acrylic moves about eight times more than glass with temperature, roughly 0.2 inch across a 48-inch pane over a 100-degree swing. Glass is puttied rigidly; acrylic cannot be.

• Undersize the pane by about 1/8 inch in each direction for a small window, more for a large one, so it has room to grow.
• Bed it in flexible sealant, silicone or butyl glazing tape, not hard putty.
• Use glazing points or a stop rather than screws through the sheet where you can.
• If you must screw through it, drill holes at least 1/16 inch oversize, use rubber or nylon washers, and snug the screws rather than cranking them. Drill with a bit meant for plastic or run a standard bit slowly with the film on; acrylic cracks at holes made carelessly.
• Install on a mild day so the pane is near its mid-range size.
• Leave the protective film on until the pane is in and the sealant has skinned.
• Clean it like acrylic afterward: wet cloth, no ammonia, no paper towels. Scratches polish out; see our scratch repair guide.

When to use polycarbonate instead

If the pane is at ground level facing a lawn, a driveway, or a ball field, or if it is a workshop window near a bench, polycarbonate's 250-times-glass impact resistance is worth its price and its tendency to scratch. Buy a UV-coated grade with the coated face out or it will yellow. For everything else, acrylic stays clearer, polishes, and costs less.

Sources

• Acme Plastics: Cut-to-size acrylic and 1/4 x 24 x 48 clear extruded acrylic
• ShapesPlastics: Plastic replacement windows
• Freckleface: Garage door window replacement
• The Home Depot: OPTIX 1/8-inch plexiglass
• ePlastics: Cut-to-size plexiglass acrylic sheets
• ACRYLITE Glazing technical information, 1320-1B (PDF) and ACRYLITE: Fabrication and installation guidelines for glazing
• Kastlite: Plastic sheet thickness guide and Bramur: Can I use plexiglass to replace shed and garage windows