Quick answer: Bay window installation costs $2,500–$12,000 in Los Angeles — replacing an existing bay window is the cheapest option, while converting a flat window to a bay window costs more due to the added framing and exterior work. APLA Construction (CA Lic #1136359) handles this throughout Greater Los Angeles.
A bay window adds light, architectural character, and a sense of space to any room, making it a favorite upgrade for Los Angeles homeowners looking to enhance a living room, kitchen, or bedroom. Whether you are updating a traditional home in Pasadena or a bungalow in Culver City, a bay window creates a bright focal point and a cozy nook. APLA Construction is a licensed LA general contractor (CA Lic #1136359) that installs bay and bow windows.
Bay window installation in Los Angeles typically costs between $2,500 and $9,000 per window installed, depending on size, style, and whether structural changes are needed. A 2026 guide:
| Item | Typical Cost |
| Replacing an existing bay window | $2,500 to $5,000. |
| Converting a flat window to a bay window | $4,000 to $9,000, since it requires framing, a projecting sill, and exterior work. |
| Bow windows (four or more panels) | often $5,000 to $12,000 due to size. |
Cost drivers include the window unit itself, structural framing to create the projection, a new roof or support below, interior and exterior finishing, and energy-efficient low-E glass for Title 24.
Simply replacing an existing bay window is far cheaper than cutting a larger opening in an exterior wall, which requires a header, support, and weatherproofing. The size, number of panels, and material all affect price.
Bay windows are popular for creating reading nooks and breakfast areas in homes across the Valley and Westside. We ensure proper flashing and waterproofing so the projection stays leak-free, and we match trim to your home. This work pairs well with a broader remodel.
Replacing an existing window usually does not require a permit; enlarging an opening or altering the structure does. APLA handles permits when needed.
Modern bay windows with low-E, dual-pane glass meet Title 24 and are energy efficient. We install compliant units.
Most rooms with an exterior wall can accommodate a bay window, though structural and setback factors apply. We assess feasibility for your home.
A replacement takes 1 to 2 days; a new bay window opening takes 3 to 5 days including finishing.
APLA Construction installs bay and bow windows across Los Angeles. Licensed CA Lic #1136359 — verify on CSLB. Call (818) 818-4419 or email info@aplaconstruction.com for a free estimate.