Services · Skylights
Skylight Installation in Los Angeles: Fitting and Flashing
The flashing system around a skylight matters more than the unit itself. Four-sided flashing, not a bead of sealant and hope.
- Four-sided flashing
- Fixed, venting or tubular
- Separate permit filed
Last reviewed by the Los Angeles Roofing Masters crew
Natural Light Added With a Four-Sided Flashing System That Holds
Fixed, venting, and tubular skylights installed or replaced - flashing integrated, not beaded.
What Skylight Installation and Repair Actually Involves on an LA Roof
A skylight project is two jobs: placing the unit and sealing the curb around it correctly.
Two Kinds of Callers
Some homeowners come to us ready to add a skylight. They want more natural light in a kitchen, a living room, or a hallway with no windows. Others come to us because they already have a skylight - and water is dripping from somewhere near the ceiling on the first hard rain of the season.
The Real Culprit
Here's what most homeowners don't realize about skylight leaks: the skylight itself is rarely the problem. The unit is intact. The glass is sealed. The mechanism works. The failure is almost always in the curb flashing system - the four-sided metal and membrane assembly that seals the transition between the raised skylight frame and the surrounding roof surface.
We handle both types of projects. New skylight installation in Los Angeles includes selecting the right unit, cutting and framing the opening, building or setting the skylight curb (the raised frame that elevates the unit above the roof plane), and integrating the flashing system into the surrounding roofing material. Skylight replacement and leak repair starts with pulling back the existing flashing to assess the curb, identifying where the separation occurred, and rebuilding that assembly correctly.
Both projects end in the same place: a properly sealed skylight that handles LA's thermal cycles without letting water in.
Installing and Repairing Skylights on Flat and Low-Slope Roofs Across Central LA
Central LA's Mid-Century Modern housing stock creates specific skylight challenges that pitched-roof installations don't share.
Our dispatch point on Alta Vista Blvd sits in the middle of the neighborhoods where this work is most concentrated. Silver Lake, Los Feliz, and Culver City together contain one of the largest per-capita inventories of flat-roof and low-slope residential properties in the country. These homes - many of them mid-century modern construction from the 1950s and 1960s - were often built with skylights as part of the original design. Many of those original units are still in place.
Higher Curbs for Slower Drainage
Flat-roof skylight installation in Los Angeles requires a higher curb than pitched-roof work. On a flat or low-slope roof, water doesn't sheet off quickly. It pools and moves slowly toward drains. A skylight curb set too low becomes a point where water builds against the skylight base during a sustained rain event. The industry minimum is four inches. On truly flat roofs, we often go higher, depending on how the drainage system performs around the skylight perimeter.
Debris Accelerates Failure
There's another factor specific to this housing stock. Flat roofs accumulate debris. Eucalyptus leaves, palm fronds, wildfire ash, and construction dust collect around the skylight curb base between rain events. That debris holds moisture against the flashing system. Over several LA dry seasons - and the thermal expansion and contraction that comes with them - that persistent moisture accelerates seal failure in ways that don't happen on steeply pitched roofs.
We account for all of this before specifying the installation.
Fixed, Venting, or Tubular: Choosing the Right Skylight for Your Home and Roof
The right skylight type depends on the room it serves and what your roof geometry allows.
The skylight conversation almost always starts with the same assumption: a skylight is a skylight. Once the difference between the three main configurations is clear, the decision usually becomes straightforward.
Fixed Skylights
The most common type - sealed units that allow light in but don't open. They're the right choice for rooms where heat release isn't a concern, or where the structural framing doesn't allow for an operable unit. Installation is straightforward. There's no mechanical component to maintain. Long-term performance depends entirely on the flashing system and the quality of the unit itself.
Venting Skylights
Open mechanically or manually to allow hot air to escape. In LA's flat-roof and low-slope residential market, this matters. Flat roofs have limited passive exhaust pathways. Attic temperatures on un-ventilated flat-roof homes regularly reach 130 to 150 degrees Fahrenheit in summer. A venting skylight positioned at the highest point of a room can release that heat load in a way that a fixed unit cannot. They cost more upfront and require mechanical maintenance over time - but for the right room in the right home, the performance difference is real.
Tubular Skylights
Sometimes called solar tubes. A tubular skylight runs a highly reflective metal tube from a small dome on the roof surface down through ceiling framing to a diffuser lens in the room below. The roof penetration is much smaller than a full skylight opening - typically ten to fourteen inches in diameter. That makes them useful in interior hallways, bathrooms, and closets where structural framing doesn't allow for a full skylight cut. Older LA homes are full of these rooms. If you have an interior bathroom with no natural light, a solar tube installation is worth asking about. The flashing requirements are simpler, but they still need to be done correctly.
Brand Compatibility Matters on All Three Types
Velux and FAKRO are the two dominant manufacturers in the US residential market. Proper skylight installation in Los Angeles requires using the brand-specific flashing kit that corresponds to the unit being installed. Using a generic flashing kit - or improvising with sealant - voids the manufacturer warranty on the unit itself, regardless of who does the work. We follow the kit specifications exactly.
The Flashing System Around Your Skylight Matters More Than the Unit Itself
Most skylight leaks in Los Angeles are flashing failures - not unit failures.
Before replacing any skylight unit due to a suspected leak, the flashing system needs to be assessed independently. The unit may be perfectly intact.
Here's the mechanism behind most LA skylight leaks. Nights in Los Angeles are cool. Afternoons are hot. That daily temperature swing - which in inland communities can span 35 to 40 degrees Fahrenheit in a single day - causes the materials around your skylight to expand and contract on a repeated cycle. Thermal cycling sealant failure is the progressive degradation of perimeter sealants driven by this cycle. A bead of sealant applied around the skylight frame perimeter loses adhesion at the edges over several years of this movement. Eventually it separates at one point. Water tracks under the curb flange during the first significant rain. It appears on your ceiling days later, often several feet from the skylight itself, because it followed the roofing material downslope before finding a gap into the structure.
A properly built curb flashing system doesn't rely on sealant alone. It uses stepped metal flashing integrated into the surrounding roofing material on the upslope side, counter-flashing that overlaps the curb face, and a membrane layer that ties all four sides into the waterproofing plane of the roof itself. No single point of sealant failure can create a leak path through a properly stepped and counter-flashed curb. That's the difference between a flashing system and a bead-only seal.
We build the four-sided system. Not just the bead.
Our Skylight Standards
Curb Height, Flashing Integration, and Debris Management
Every skylight we install or reseal is held to the same four-point standard. Our approach to skylight installation in Los Angeles covers four areas that directly affect long-term performance:
We size curb height to the roof's drainage behavior, not just the code minimum. Flat and low-slope roofs with slow drainage get taller curbs. We measure drainage performance first.
Step flashing on the upslope side, counter-flashing at the curb face, membrane tie-in on all four sides. No bead-only perimeter seal as the primary waterproofing layer.
Velux, FAKRO, and equivalent manufacturer kits are installed per specification. No substitutions. This protects the unit warranty.
On flat and low-slope roofs, we establish and document a debris clearance zone around each skylight curb. Debris accumulation against the curb base is a long-term failure accelerator. We note it in post-installation documentation and flag it during any subsequent roof inspection.
These aren't add-ons. They're the standard.
What a Skylight Installation or Replacement Involves From Start to Sealed
A skylight project follows a clear sequence - from opening assessment to final seal verification.
Diagnostics and Site Assessment
Before any cut is made or any flashing is pulled, we assess the roof surface around the skylight location. For new installations, that means checking the structural framing below, the roof material condition at the proposed cut zone, and the drainage pattern around the target area. For replacements and leak repairs, it means pulling back the existing flashing to see the full condition of the curb - whether the wood is sound, whether the membrane is intact, and exactly where the seal has failed.
On flat-roof homes in central LA, we also check the surrounding roof membrane for signs of ponding adjacent to the proposed curb location. A skylight installed into a low spot creates a persistent drainage problem.
Installation and Flashing Integration
New installations begin with framing the opening and building or setting the curb. The flashing kit is installed per manufacturer specification - step flashing first on the upslope side, then the counter-flashing, then membrane integration on all four faces. The curb is set to the specified height for the roof geometry. The unit is placed and fastened according to the manufacturer's torque and fastener pattern requirements.
For replacements, we remove the existing unit and all existing flashing. The curb is assessed and repaired or rebuilt as needed. New flashing kit. New unit if specified. Same four-sided integration process.
Post-Installation Verification
After the flashing is in place and the unit is seated, we run a controlled water test - directing water at the upslope curb face and monitoring the interior for any evidence of penetration. We document the installation with photographs of the flashing sequence, the curb height measurement, and the final sealed condition. That documentation stays with your project file and is available for permit inspection if required.
On flat-roof properties, we confirm that the debris clearance zone is established and note it in the post-installation summary.
Skylight Work Across Los Angeles - Silver Lake, Los Feliz, Culver City, and Beyond
We complete skylight installation and repair projects across the greater Los Angeles area.
Our skylight work is concentrated in the flat-roof and low-slope neighborhoods closest to our Alta Vista Blvd dispatch point - Silver Lake, Los Feliz, Culver City, West Hollywood, and Mid-City LA - but we serve the full regional footprint. That includes the San Fernando Valley, the South Bay, the San Gabriel Valley, and communities throughout the Inland Empire. Pasadena, Glendale, Burbank, Long Beach, Torrance, and Santa Monica are all within our regular scheduling area.
Frequently Asked Questions
Skylight questions from LA homeowners considering installation or dealing with a drip.
Why does my ceiling stain appear far from the skylight?
Water tracks under the curb flange during the first significant rain, then follows the roofing material downslope before finding a gap into the structure. It appears on your ceiling days later, often several feet from the skylight itself.
Do I need to replace my skylight if it's leaking?
Rarely. Most skylight leaks in Los Angeles are flashing failures, not unit failures. The unit may be perfectly intact. We assess the curb flashing system independently before recommending any unit replacement.
Which skylight type is right for my room?
Fixed skylights suit rooms where heat release isn't a concern. Venting skylights release trapped heat in flat-roof homes. Tubular skylights, or solar tubes, bring light to interior hallways, bathrooms, and closets where a full cut isn't possible.
Does the flashing kit affect my warranty?
Yes. Using a generic flashing kit, or improvising with sealant, voids the manufacturer warranty on the unit regardless of who does the work. We install Velux, FAKRO, and equivalent brand-specific kits exactly to specification.
Why does a flat roof need a taller curb?
On a flat or low-slope roof, water doesn't sheet off quickly. It pools and moves slowly toward drains. A curb set too low lets water build against the skylight base. The industry minimum is four inches, but we often go higher based on drainage performance.
How do you confirm the skylight is sealed?
After the flashing is in place and the unit is seated, we run a controlled water test, directing water at the upslope curb face and monitoring the interior for any evidence of penetration. We document the flashing sequence, curb height, and final sealed condition.
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