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  Georgian Built-Up Cornice  
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1. To ensure a professional job, careful layout is a prerequisite. Begin by snapping a chalk line on the ceiling around the perimeter of the room, 5 1/2 in. out from the wall. Snap a second chalk line on the walls, 3 1/4 in. down from the ceiling. Measure from the corners. Unlike other crown molding designs, this cornice will absorb most inconsistencies between corner and mid-wall measurements so that inconsistencies in reveal lines are not apparent.  
2. Install continuous 3/4 in. backing on the both the walls and the ceiling. The wall backing can be any width of material, as it fastens directly to the studs. On walls that are parallel with the joists, the ceiling backing should be wide enough to almost reach the wall, so that fasteners will penetrate through the drywall to the framing backing. On walls perpendicular to the joists, a strip of 1x2 works fine. Apply panel adhesive wherever framing backing is lacking.  
3. The Soffit (Crown #3) must be installed carefully or the job will not progress professionally. To provide adequate backing in the corners and at mid-spans, install mid-span supports approximately 6 ft. on center. Cut the supports 2 1/2 in. long (if the ceiling backing is 3/4 in. stock); toe nail or screw the supports to the ceiling backing.  
Cut and miter all outside and inside Soffit corners. Join the miter with a biscuit to ensure a tight-fitting flush joint. Fasten the Soffit to the wall backing and to mid-span supports, then glue and fasten all Soffit corners.


Mid-span and corner backing blocks can be eliminated if the Fascia is installed first, but holding a proper reveal on the back side of the fascia, just above the cove cut, is more difficult without backing blocks.  
4. Fasten the Fascia (Crown #2) to the ceiling backing. The Fascia cove must point down and towards the wall. The bottom of the Soffit must be flush with the top shoulder of the Fascia cove—so that the Fascia and cove are proud of the Soffit. Nail through the Fascia into the Soffit.

5. Cut and install the bed molding.  
6. Install the Crown (Crown #1) next. First, scribe or snap a chalk line 1 1/4 in. up from the bottom of the Fascia.  
Fasten the crown molding as close as possible to that line. The 1 1/4-in. wide reveal will absorb most inconsistencies in the ceiling.  
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