Replacement Window Cost Calculator

Bow Window Replacement Cost Calculator

Build the curve first. Then estimate the complete installed project.

A more beautiful view.
A brighter tomorrow.

1

Bow Geometry Builder

Create your bow window dimensions, then calculate the installed cost.

Overhead view (top down)

12345TOTAL WIDTH 96 inPANEL WIDTH 19.2 in · 18 in projection
1Fixed
2Opens
3Fixed
4Opens
5Fixed
Support, roof & finish scope

No personal information required. Instant planning estimate.

Your curved assembly

Estimated installed cost for a 5-panel bow window (96 in wide × 54 in high × 18 in projection)

Showing the default estimate.

$9,800 – $22,400Estimated installed cost
$15,100Typical planning figure
$1,960 – $4,480Per panel
$1,225 – $2,800Per linear foot

Estimated cost breakdown

Bow unit$5,400 – $10,800
Operable-panel premium$800 – $2,200
Removal & installation$2,400 – $4,800
Whole-unit support$600 – $1,600
Roof & flashing$600 – $1,600
Seat & trim$600 – $1,800
Opening repairs$0 – $1,200
5 equal panels19.2 in each
2 operable panelsAlternating opens
New cable supportWhole-unit support at mullions

4, 5, or 6 panels — same opening, different curve

Same 96-inch total width. More panels create smaller equal sections and a smoother, gentler curve.

4 panels

123424.0 inequal panels

5 panels

1234519.2 inequal panels

6 panels

12345616.0 inequal panels

Choose where the bow vents

Venting adds fresh air and affects hardware, screen, product, and labor cost.

All fixed

Maximum light, no operating panels.

Outer pair opens

Panels 1 and 5 operate.

Alternating opens

Panels 2 and 4 operate.

???

Custom / unknown

Confirm the exact panel schedule.

Support the whole curve

A bow window needs continuous support at each mullion.

Roof / head flashing
Seat board
  • Head board attaches the cable support.
  • Cable points align with mullions.
  • Knee braces may be specified for larger projections.

Replace an existing bow or create a new projection?

Your project scope affects the total cost.

Photorealistic illustration of a five-panel bow window replaced in an existing brick wall opening
Photorealistic illustration

1:1 replacement

Remove the old bow, verify support and flashing, then install a new unit in the existing opening.

Lower-cost path
Photorealistic illustration of a new five-panel bow projection with roof cap and support brackets
Photorealistic illustration

Flat-to-bow conversion

Frame a projection, add support, water management, and complete interior and exterior trim.

Higher-cost, more labor

Bow is not Bay

A bow window is a gentle curve of equal panels. A bay window has three angled panels.

Bow Window

4, 5, or 6 panels
  • Equal-width panels
  • Continuous gentle curve
  • All panels in the same assembly

Bay Window

3 panels
  • Center plus two angled sides
  • 30° or 45° corners
  • Center panel is often wider
Open Bay Window Calculator →

Ask for a complete bow window quote

Use this checklist to compare quotes and make sure the complete projecting assembly is included.

  • Panel schedule (size and type)
  • Venting pattern (which panels open)
  • Exact width, height, and projection
  • Support at mullions (cable or structural)
  • Head and seat boards (material and size)
  • Flashing and roof (water management)
  • Interior and exterior trim
  • Existing damage or repairs
  • Product and labor warranty