Skylight Types and Services
Fixed, venting and tubular units cover most homes. Replacement and leak repair are the jobs on skylights already in the roof.
Fixed (Deck-Mounted) Skylights
A fixed skylight doesn't open. It's the simplest unit and the least likely to leak, and HomeGuide says fixed models resist leaks better than venting ones. Deck-mounted means the frame sits directly on the roof sheathing with no site-built curb. VELUX, for example, rates its deck-mounted fixed skylight for roof pitches from 14° to 85°, which is about 3:12 and steeper. On a flatter porch or addition roof, a curb-mounted unit is the right choice. Fixed units go where you want light without airflow: stairwells, vaulted living rooms, over a kitchen island.
Venting Skylights, Manual and Solar
A venting skylight opens to let out hot or humid air, which is why it shows up over bathrooms and kitchens. Manual units open with a crank or pole. Electric units need a wire run, and solar-powered units charge their own motor and work by remote, with no wiring, as HomeGuide notes. A venting unit has more seals than a fixed one, so it's worth an annual look at the gaskets.
Tubular Skylights (Sun Tunnels)
A tubular skylight is a small dome on the roof, a reflective tube through the attic, and a round diffuser in the ceiling. It lights a hallway, closet or windowless bath without framing a full light shaft. The tube runs through the cold attic, so the tube and the ceiling ring should be sealed and insulated. Otherwise warm, moist room air can reach the cold dome and condense.
Skylight Replacement During a Re-Roof
If your skylight is the age of the roof, replace them together. With the shingles off, the old unit lifts out, the curb or opening gets checked for rot, and the new unit's flashing kit laps correctly into new underlayment and shingles. Doing it later means cutting into a new roof and patching shingles around it.
Skylight Leak Repair and Flashing Kits
A wet ceiling under a skylight has a few possible sources. It could be the flashing kit, the seals between the glass and the frame, or condensation. Condensation shows up on cold, dry days when warm room air hits cold glass, and it isn't a roof leak at all. Flashing leaks show up during rain or snowmelt. Skylight flashing kits come with adhesive underlayment that wraps the frame, and the self-adhered membrane maker GCP lists skylights among the trouble spots its membrane protects. A tube of roof cement around the curb is a stopgap, not a repair. When the flashing has failed, the fix is lifting the surrounding shingles and fitting a new kit.
Why Southfield homeowners call Southfield Elite Roofing
- Free roof inspection
- Written scope and price before work starts
- One local roofing contractor per request
- Southfield homes and buildings only
- No fee for homeowners
Skylight Installation Cost in Southfield
HomeGuide's national skylight guide (August 2025) gives these installed figures. They're estimates, not quotes.
New skylight, fully installed
$1,600 to $4,200.Replacing an existing skylight
$800 to $2,400.Fixed unit
$1,500 to $4,000 installed.Venting unit
$1,600 to $4,700 installed. Electric and solar models cost the most.Tubular skylight
$500 to $1,000 installed.Interior finish
Drywall for the light shaft runs $300 to $1,500 or more.
The roof work and the inside finish are often separate trades. Ask whether the quote includes framing, the light shaft, drywall and paint, or stops at the roof.
How a Skylight Installation Runs
- 1
Check the Framing and the Pitch
The contractor finds the rafters or trusses from the attic, picks a spot that avoids cutting them where possible, and confirms the roof pitch suits a deck-mounted unit.
- 2
Frame and Cut the Opening
Headers go in where a rafter has to be cut, then the deck opening is cut to the unit's rough-opening size.
- 3
Set the Unit and the Underlayment Collar
The skylight is fastened to the deck, and the adhesive underlayment wraps the frame and laps onto the roof underlayment.
- 4
Flashing Kit and Shingles
Step flashing or a one-piece kit goes on in the order the manufacturer specifies, woven into the shingle courses.
- 5
Light Shaft Inside
Framing, insulation and drywall finish the shaft. On a tubular unit, the tube is sealed and the diffuser fitted.
Things to Know About Skylights in Southfield
Energy rating
ENERGY STAR certifies skylights through independent NFRC testing, and its criteria differ by climate zone, so check that the label covers your zone.Snow sits on skylights
A typical winter here drops around 45 inches of snow (NWS Detroit normals), and some of it sits against the uphill side of the curb. The flashing has to hold through melt-and-freeze cycles, so get the manufacturer's kit and not a home-made one.Permit
The City of Southfield's permit list includes re-roofing. If the skylight goes in during a re-roof, the contractor's permit covers the roof work. Ask the city whether a new roof opening needs its own permit.