Skylight Replacement in Santa Clarita: Stop the Leak, Cut the Heat

A leaking skylight needs full replacement, not just new caulk, once the flashing or seal around the frame has failed — recaulking the glass won't fix a leak coming from underneath it. Santa Clarita Roofing Services swaps in double-pane, low-E units during replacement, cutting both the leak and the heat gain in one visit.

How do you tell a flashing leak from a glass leak?

Water tracking down the inside of a skylight shaft during or right after a storm almost always means the flashing or the seal around the frame has failed — not the glass. An actual failed pane is rare on a modern skylight and shows up differently, as fogging or a milky haze trapped between the panes of an insulated unit rather than an active drip. The distinction matters because water doesn't respect where it entered: once it gets past a bad flashing seam, it travels along the deck and can stain drywall several feet from the skylight itself, which is why a leak that looks small from inside the house is often a bigger job on the roof than it appears.

What should you do right now if it's actively dripping?

Set a bucket at the drip point, and if the ceiling is sagging with trapped water, push a small hole through the lowest point from below so it drains through one controlled spot instead of spreading across the drywall. Don't climb up to look at it yourself in the rain — that's how one problem becomes two.

Skip the tube of clear silicone from the hardware store aimed at the visible gap on the outside. Caulking over the leak seals the symptom, not the source, and it hides the real failure point from whoever diagnoses it next — including us. Santa Clarita Roofing Services takes roofing calls day or night, and the crew covers 21 communities across the Santa Clarita Valley, so getting eyes on the flashing doesn't have to wait for a weekday.

Why does the flashing fail before the skylight itself does?

Flashing is thin metal doing a hard job: it has to flex with the roof through every heating and cooling cycle without ever opening a gap at the seams. Years of that movement work the fasteners loose and fatigue the metal at the corners, which is where step flashing meets the curb and where leaks most often start. The rubber gasket sealing the glass to the frame goes the same way — it hardens and shrinks with age long before the glass itself gives out.

That's also why a skylight installed correctly the first time, with proper step flashing tied into the surrounding shingles or tile course by course, tends to outlast one where the flashing was set on top of the roofing material instead of woven into it.

What actually makes a replacement skylight energy efficient?

The glazing does most of the work. Double- or triple-pane units with a low-E coating block UV and infrared heat while still passing visible light, which is the difference between a skylight that floods a room with glare and heat and one that just lights it.

• Double- or triple-pane glazing with a low-E coating that blocks UV and infrared while still passing visible light
• An insulated curb or frame in place of bare aluminum, which conducts heat straight into the room below it
• Laminated inner glass, which holds together if the outer pane cracks and blocks more heat than tempered glass alone
• The right size for the room — an oversized skylight loses the efficiency argument no matter how good the glass underneath it is

Curb-mounted or deck-mounted — does it change the leak risk?

A curb-mounted skylight sits on a raised wooden box built up from the roof deck, and replacement usually means swapping the glass unit on top while the curb and its flashing stay in place — a faster job if the curb itself is sound. A deck-mounted skylight sits flush with the roofline with no curb underneath it, which is more common on newer builds and looks cleaner, but it puts the flashing seam closer to where water actually flows across the roof.

Neither style is inherently more leak-prone once it's installed correctly. The failure point in both cases is the same: whether the flashing was properly integrated with the surrounding roofing material or just sealed at the edges.

Does every leaking skylight need full replacement?

Not always. If the leak is caught early — a single failed bead of sealant with the flashing and glass otherwise sound — a targeted reseal can buy several more years, and it's the cheaper call to make. Full replacement earns its cost once the flashing is corroded, the curb has started to rot, or opening the unit up for a lasting repair means pulling back surrounding shingles or tile anyway.

At that point, resealing the old glass and frame just delays the same job later without picking up any of the efficiency upgrade that comes with new glazing. We'll tell you which situation you're actually in before recommending either one.

Is a foggy skylight the same problem as a leaking one?

No. Fogging between the panes of an insulated skylight means the seal on the unit itself has failed and let moisture in — that calls for replacement, but it's a different failure than an active drip, which is almost always coming from the flashing around the frame, not the glass.

Can a skylight be replaced without disturbing the roofing material around it?

Not if it's done right. Resetting the flashing correctly means pulling back a few courses of the surrounding shingles or tile so the new flashing can be woven back in, which is exactly why a surface-level patch doesn't last as long as a full flashing reset.