Tile • Shingle • Flat Roof Skylights
A leaking skylight is often a flashing and drainage problem—not simply a bad bead of sealant. We open the roof, trace where the water is traveling, rebuild the underlayment and flashing, and give the water a clear path back onto the roof.
Diagnosis Before Demolition
Skylights drain much like chimneys. Water must move around the uphill side, enter protected channels along both sides, and return safely to the roof below. If one part of that route is blocked, flattened, too short, or lapped incorrectly, water can escape onto the underlayment and show up inside farther downslope.
If the frame, glass, acrylic dome or glazing seal has failed, the skylight itself may need replacement. If the unit is sound but the surrounding flashing or underlayment is wrong, it may be possible to keep the skylight and rebuild the roof system around it.
Flashing Anatomy
The best-looking detail still has to drain. Our goal is to preserve the channel capacity, maintain positive laps, and keep the primary and secondary water-control layers working together.
| Head / saddle flashing | Diverts water around the uphill side of the skylight and feeds it into the side channels instead of allowing it to collect behind the frame. |
|---|---|
| J-channel / tile pan | Carries water down each side. The raised edge is functional: it helps contain water when flow increases or debris narrows the channel. |
| Tile clearance | Tiles are trimmed or shaped to sit correctly without crushing the pan lip. Adequate space also makes the waterway easier to maintain. |
| Downslope discharge | Each side pan must finish back on top of tile. When a skylight is close to the eave, the channel may need to continue through a properly cut bird stop or eave closure. |
| Secondary waterproofing | Underlayment and, when appropriate, peel-and-stick membrane protect the deck beneath the primary tile-and-metal drainage system. |
Our preference: where the roof geometry allows, we often fabricate an approximately 8-inch-wide side pan instead of the narrower 6-inch detail commonly seen. The final size is selected for the actual skylight, tile profile and available roof space.
How We Repair It
We lift and stage the surrounding tile, then open the roof below and beside the skylight so we can follow the actual water path.
Damaged material is removed and the underlayment is properly lapped. Options include RightStart UDL, 30-pound felt or another compatible synthetic system.
When appropriate, we add a peel-and-stick membrane around the skylight. This project used Titanium PSU-30, then received the normal underlayment integration above it.
We install the saddle, side pans and discharge details, restore the tiles with proper clearance, and verify that water can move out of the assembly.
Real Zenith Project
These are actual field photos from a large skylight-bank repair. They show why a dependable repair involves the roof around the skylights—not just the visible frame.
Maintenance Matters
Leaves and roof debris can force water sideways even when the metalwork is sound. Skylight maintenance should include clearing both side channels, checking the uphill saddle area and removing anything that blocks the downslope outlets.
Questions We Hear
We work around skylights on tile, shingle and low-slope roof systems. The correct metal and underlayment details depend on the skylight style and roof assembly, so we inspect before recommending a scope.
Surface sealant can help at a confirmed sealant joint, but it cannot correct a buried flashing lap, failed underlayment or blocked side pan. A lasting repair addresses the path the water follows.
The raised lip helps contain water. We prefer to shape the tile for clearance and preserve the channel whenever possible, balancing appearance with the drainage function that protects the roof.
There may not be enough tile below the unit for a normal pan discharge. In those conditions, the outlet can require a custom route through the bird stop or eave closure so it drains outside rather than beneath the tile.
Not in every assembly. We select the waterproofing for the roof, existing materials and repair conditions. Peel-and-stick is a useful upgrade at critical transitions, but it still must be integrated with correctly lapped underlayment and working metal flashing.
Zenith Roofing Services repairs skylight leaks throughout San Diego County, including Escondido, San Marcos, Vista, Oceanside, Carlsbad, Encinitas, Poway, Fallbrook, Temecula and surrounding communities.
Share the property address, roof type, when the leak appears and whether the skylight glass or frame looks damaged. Roof and interior photos help us understand the water path before we contact you.
Send us photos of the skylight, roof and interior stain. We’ll help identify the right next step.