My builder put arches with 90 degree edges in my house;however, bullnose arches fit the design. Is there anyway that I can get the effect of bullnose arches without taking down the drywall?

Thanks

Do you mean bullnose edges on the corners of the arch?

Trimtex makes a bullnosed corner for sheetroock of PVC. It should be easy to add it over the existing and refinish with a couple coats of finishing mud

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