- A decorative arch inside an existing non-structural opening is the simplest condition.
- Raising, widening or changing structural framing is a different project from shaping the opening.
- The finish quality depends on a consistent radius, corner treatment and texture blend.
How an interior arch is built
For a typical decorative conversion, the existing trim is removed and the opening is verified. Curved framing or purpose-made arch components establish the shape, drywall follows the radius, flexible corner bead defines the edge, and multiple finish coats create a smooth transition into the wall.
The arch should be laid out full-size before finishing. A shallow segmental arch, a half-circle arch and a softer elliptical arch create very different proportions. The width and ceiling height determine which one looks intentional rather than squeezed into the opening.
What does a doorway arch cost?
A decorative arch formed within an existing non-load-bearing opening often falls in an early planning range of about $2,500 to $5,000, including demolition, shaping, drywall finishing and normal paint blending. Custom trim, difficult plaster matching or extensive adjacent finish work can move the project toward $5,000 to $8,000-plus.
If the opening will also be widened or raised, or if structural framing and utilities must change, it should be priced as an opening alteration rather than a decorative arch alone. That broader scope can exceed the range above.
Details to decide before construction
- Arch profile: half-round, segmental, elliptical or a custom radius.
- Finished edge: clean drywall return, wood casing, stone or another trim material.
- Wall texture and paint: smooth walls reveal irregular curves more readily; heavy texture requires controlled blending.
- Baseboards and flooring: confirm how the opening meets both rooms at the bottom.
- Lighting and switches: determine whether electrical devices conflict with the new curve or opening width.
When permits or engineering enter the conversation
A decorative shape built inside an opening is different from changing the framing that supports the structure. When the opening is widened, raised or reframed, the local building department may require a permit. In the City of Los Angeles, LADBS guidance calls out new doorways and alteration of wall framing around doorways. Confirm the project address and exact scope before work begins.
Photos that let us evaluate the idea
- A centered photo of the full opening, including floor and ceiling.
- Both wall faces and nearby switches, vents or built-ins.
- Opening width, opening height, wall thickness and ceiling height.
- One inspiration image showing the exact arch profile you prefer.
Planning ranges are general starting points, not a bid or guarantee. A written proposal requires review of the property, final scope, selected materials, access, jurisdiction and applicable approvals.