How to Build Roof Gable End Cornice Returns
- 1). Measure the area from the end of the gable fascia to an area approximately 6 inches underneath the roof beam at each end of the roof using a tape measure.
- 2). Mark a piece of plywood in a triangular design to fit the area you measured in Step 1 using a framing square. The triangular wood becomes the cornice. Repeat for the other end of the roof.
- 3). Cut out the cornice pieces using a circular saw and straight-edge guide. You need two cornice pieces.
- 4). Test-fit the cornice pieces over the ends of gable on the roof. Install using finishing nails and a hammer into the ends of the beams driven up into the underside of the gable fascia.
- 5). Embed the heads of the nails below the surface of the wood using a nail set. Be careful not to split the cornice pieces.
- 6). Caulk the seams between the fascia boards and the cornice using silicone caulking and a caulking gun.
- 7). Finish the cornice returns by siding them according to the manufacturer's directions.
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