* Trace the dome onto cardboard in an upside-down position and transfer four alignment lines onto the outline. Since this outline includes the flange, it’s larger than the hole you
need to cut in the ceiling.
* Scribe a second, smaller circle inside the outline by setting a compass or scribe slightly less than the width of the flange and following along the outline. Use a straightedge
and marker to connect the opposite alignment marks, forming a cross. Cut out the inside circle to make your template.
* Screw the cardboard template to the ceiling. The alignment cross may be used to center a round dome or to make an oval dome parallel with a wall. Transfer the alignment
marks to the ceiling with a pencil to guide positioning of the domes that are oval or imperfectly round.
* Cut through the drywall and framing at the edge of the template. Add re-enforcement framing as specified by a qualified structural engineer. Add trimmers and blocking to the
dome edges at screw locations. Add insulation if necessary, above the dome.
* Prepare for a fixture box if a light fixture or fan will be hung in the dome. Drill a 1" hole in the center of the dome. Raise framing above the ceiling opening to secure an electric
fixture box above the center of the opening. Dome specifications will determine how far to recess the fixture box from the face of the ceiling. Typically, the face of the fixture box
should be flush with the finished (visible) face of the dome. You may temporarily attach the dome to help position the fixture box.
* Cut a hole for the light fixture wiring in the center of the dome. A hole saw that’s slightly bigger than the round electrical fixture box works. For larger or more challenging
openings, use a spiral saw to cut the outline of the fixture box in the dome.
* Apply polyurethane construction adhesive to the back of the dome flange. Lift the dome into place with helpers, aligning the ceiling and dome alignment marks and fitting the
dome around the electrical box. Attach the flange of the dome to the blocking through the ceiling with drywall screws. Countersink the screw heads slightly.
* Hang your light or fan and caulk all air gaps through and around the fixture box. Caulk the seam where the dome flange meets the ceiling. Cover the fastener heads with joint
compound. Finish the dome with ceiling paint.
