Want to bring daylight into a dark middle room, or replace a leaking skylight on the flat roof? Send a few details and you’ll get a straight answer on what’s involved — and how to do it without creating a leak — from one vetted, licensed San Francisco roofer.
Tell us the room you want lit, the roof type above it, and whether this is a new skylight or a replacement. With skylights, the flashing is everything.
Why skylights make so much sense in an SF home
The classic San Francisco floor plan — a deep, narrow home on a tight lot, with rooms in the middle that are far from any window — leaves dark interior spaces that no lamp really fixes. A skylight or a tubular daylight device is often the single best way to bring natural light into a windowless hallway, bath, kitchen, or stair. On the flat and low-slope rear roofs common here, a curb-mounted skylight sits up off the membrane where it can be flashed properly; on a steep front slope, a deck-mounted unit fits the pitch. Even with the city’s famous fog, the light that comes through is soft and even — which many people prefer to harsh direct sun.
The catch is that a skylight is a hole cut in your roof, and a hole in the roof is a leak waiting to happen if it isn’t flashed and integrated correctly. That’s exactly why it’s roofing work, not just a window install. The unit itself matters less than how it’s tied into the roof: the curb height, the flashing kit, and the way it laps into the membrane or shingles. Done right, a modern skylight is dry for decades. Done as an afterthought, it becomes the leak that shows up every winter.
What a proper skylight install involves
- The right unit for the roof — curb-mounted on flat and low-slope roofs, deck-mounted on steep slopes, or a tubular daylight device for a small dark room.
- Proper curb and flashing — the flashing kit and membrane or shingle integration that actually keeps a roof penetration dry.
- Replacement of leaking or fogged units — swapping an old, failed, or condensation-clouded skylight and re-flashing it correctly.
- Light shaft framing — on a flat-roof home, building the shaft down through the ceiling so light reaches the room below.
- SF DBI permitting and, in a historic district, attention to what’s visible from the street.
Common questions
Won’t a skylight leak eventually?
Not if it’s flashed and integrated properly. The old reputation skylights have for leaking comes from cheap units and, more often, from bad flashing — a skylight set into a roof without the correct curb and flashing kit will leak, and that’s an install failure, not an inevitability. A quality unit tied into the roof the right way stays dry for the life of the roof. The flashing detail is where the money and the care go, and it’s what separates a lasting skylight from a seasonal headache.
Can I get light into a room with no exterior wall?
Often, yes — that’s exactly what skylights and tubular daylight devices are for in SF’s deep floor plans. A tubular unit is especially good for a small, fully interior room like a windowless bath or hallway: it channels daylight down a reflective tube from the roof with minimal framing. For a larger space, a traditional skylight with a built light shaft down to the ceiling brings in more light. Which one fits depends on the room and the roof above it, and that’s the first thing to sort out.
My old skylight is fogged up inside. Repair or replace?
Fogging or condensation between the panes means the sealed glazing unit has failed, and that isn’t repairable — the unit needs replacing. The good news is that a replacement is also the moment to re-flash the opening correctly, so you get a clear, energy-efficient skylight and a dry, properly integrated roof penetration in one go. If the old unit was also the source of a leak, replacing and re-flashing it solves both problems at once.
Send your San Francisco skylight details
Tell us the room you want lit, the roof type, and whether it’s new or a replacement, and you’ll get a straight read on the right unit and how it should be flashed — with no pressure to book.
No cost, no obligation — just a clear answer from the roofer who’d actually do the work.