Bay Window and Casement Window Replacement Cost
Updated 2026-06-17
Bay windows cost $1,200 to $3,500 installed for most standard vinyl configurations, and can reach $6,000 or more for large custom wood or fiberglass units. Casement windows run $400 to $1,100 per unit installed in vinyl. Both types cost more than standard double-hung windows: bay windows require structural support and multiple units, and casements carry a premium for larger panes and more complex hardware.
Use the window replacement cost calculator to estimate your total based on window type and quantity.
Bay window replacement cost
| Bay window configuration | Total installed cost |
|---|---|
| Small (3 panels, vinyl, standard size) | $1,200 to $2,200 |
| Medium (3 to 5 panels, vinyl) | $2,000 to $3,500 |
| Large or custom (wood or fiberglass) | $3,500 to $6,000+ |
| Bow window (4 to 6 curved panels) | $2,500 to $5,000 |
Bay windows carry a higher price because they need structural support: a header above and often a knee wall or cable support below. The project also involves multiple window units and more labor than a standard opening. The roof or seat below the bay may need to be built or repaired as part of the job, which adds $500 to $1,500 on top of the window cost itself. Before comparing contractor quotes, confirm whether structural carpentry is included or billed separately.
Casement window replacement cost
| Casement window size | Installed cost (vinyl) | Installed cost (wood) |
|---|---|---|
| Small (under 24 inches wide) | $350 to $600 | $650 to $1,000 |
| Standard (24 to 36 inches wide) | $450 to $900 | $800 to $1,300 |
| Large (36 to 48 inches wide) | $600 to $1,100 | $1,000 to $1,500 |
Casement windows cost more than double-hung windows of similar size for two reasons: the hardware (hinges, locking arms, and the crank mechanism) runs pricier than a sash counterbalance system, and the single large pane costs more than two smaller double-hung sashes. They also require clearance to swing outward, which rules them out wherever furniture, screens, or a patio sits directly outside the opening.
Can I replace a double-hung window with a casement without structural changes?
Often yes, if the rough opening is a compatible size. Your contractor will check whether the opening needs to be resized or reinforced. Swapping a double-hung for a casement in the same rough opening is typically a full-frame replacement with no structural surprises. The more practical question is whether there is enough clearance outside for the sash to swing fully open. In tight urban locations or on street-facing facades where overhangs sit close to the window, a double-hung or slider is usually the more workable choice regardless of cost.
Other window types and their cost range
- Double-hung: $300 to $900 installed. The most common replacement window type in the U.S. Both sashes open, so cleaning is accessible from inside without leaning out.
- Slider: $350 to $900 installed. Opens horizontally. Common in ranch-style and mid-century homes.
- Awning: $400 to $1,000 installed. Hinged at the top, opens outward. Can stay open in light rain. Often paired with picture windows below.
- Picture window: $250 to $800 installed. Fixed; does not open. Maximizes light and view at a lower cost because there is no operating hardware.
- Skylight: $900 to $2,400 installed. Requires roof penetration and flashing. Higher labor cost due to roof access and waterproofing requirements.
Is a bay window a good investment for resale?
Bay windows improve curb appeal and are a feature buyers notice, particularly at the front of a home. The typical cost recoup rate is 50 to 70 percent at resale, which is in line with other window upgrades. The return is more aesthetic and functional than financial. Bay windows also add usable interior square footage, whether as a reading nook, a dining banquette, or a window seat. Appraisers may not put a direct dollar value on that, but buyers do.
Can casement windows be made into egress windows?
Yes. Casement windows are often the most straightforward type to meet egress requirements (minimum 5.7 square feet of clear opening) because the entire sash swings open rather than sliding partway. That makes them a common pick for basement bedrooms where egress is required by code. Confirm rough opening size and sash dimensions with your contractor before ordering to make sure the installed unit will clear the egress minimums in your jurisdiction.
Choosing between bay and casement for your home
Bay windows make sense when the goal is architectural character, light from multiple angles, or an interior alcove. They are a substantial renovation, not just a window swap, and the budget should reflect that. Casement windows work best where ventilation matters most (kitchens, bathrooms) or where you want a wide unobstructed view with a clean contemporary line. Either way, a licensed window installer who can inspect your rough openings and check the existing structural framing will save you from ordering the wrong type for a given location.
Bottom line
Bay windows run $1,200 to $3,500 installed for most standard configurations. Casement windows cost $400 to $1,100 per unit in vinyl. Both offer things standard double-hung windows do not, and both cost accordingly. Use the window calculator to compare total project costs and get quotes from a licensed window contractor who can evaluate your specific openings and recommend the right type for each location.
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FAQs
Do bay windows need extra structural support?
Yes. Bay windows typically need a header above and a knee wall or cable support below, which is part of why they cost more than a standard opening.
Are casement windows harder to make into egress windows?
No, the opposite. Because the whole sash swings open, casements often clear egress requirements more easily than sliding styles, which is why they show up often in basement bedrooms.
Can a bay window be installed where a picture window is now?
Sometimes, if the wall can support the added weight and the roof or seat below can be built out. A contractor needs to check the structure before quoting the job.