The bottom sill will be a u shaped metal piece that slips over the bottom of the skylight.
How to install roofing around skylights.
Contractor larry landers demonstrates how to install roofing shingles around skylights.
Next slip individual pieces of step flashing under the shingles.
When the piece is cut mark the height of the skylight add one inch and cut.
Cover the bottom flange with a strip of membrane that extends 6 inches past the skylight s sides.
Drive roofing or flashing nails horizontally into the skylight not vertically into the roof.
Nail it to the side edges of the frame or curb of the skylight.
For ease of installation bend the cut piece of flashing to about 85 degrees.
Attach the bottom sill of the flashing.
How to roof around a curb mount skylight.
Install the bottom flashing a single piece that wraps partway around the skylight and sits on top of the roof shingles figure 3.
Cover the side flanges then the top in the same way.
The roofing felt and step flashing helps keep water from leaking around the skylight.
Cut the extensions at a 45 degree angle out from both corners of the skylight.