Skylight Repairs

A leaking skylight is one of those problems that starts as a nuisance and can quickly become a serious issue. Water getting through a skylight doesn’t always present as an obvious drip — it often tracks along the skylight frame, travels along ceiling joists or rafters, and appears as a water stain on a ceiling some distance from the skylight itself. By the time you notice the damage, the moisture has often been entering for a while. In Coffs Harbour, where rainfall events are frequent and can be intense, a compromised skylight can introduce significant water into your home in a single storm.

At Roof Restoration Coffs Harbour, Nathan Locke and his team carry out skylight repairs across the Mid North Coast. With over 25 years of experience diagnosing and repairing roof problems, full licensing, public liability insurance, and a 10-year workmanship warranty, we identify the real cause of skylight problems and fix them properly. Here’s what you need to know.

Common Skylight Problems

Leaks

Leaking is the most common and most urgent skylight problem. When water enters around or through a skylight, the cause is almost always in one of these areas:

• Flashing failure — the flashings around the skylight (head, sides, and apron) have failed, allowing water to enter at the junction between the skylight frame and the roof covering. This is the most common cause of skylight leaks and the one that most often results in water appearing at a ceiling location some distance from the skylight. See the flashing failure section below for more detail.
• Frame seal failure — the seal between the skylight glazing unit and the frame has deteriorated. This typically results in water appearing inside the frame or on the glazing surround during rain, and can eventually lead to water on the ceiling directly below the skylight.
• Glazing failure — cracked or damaged glazing allows water direct entry. See the cracked glazing section below.
• Condensation — in some cases, what appears to be a leak is actually condensation forming on the inside of the skylight and dripping. This is more common in poorly insulated or inadequately ventilated sky shafts and tends to be worst in cool conditions rather than during rain. Distinguishing between a genuine leak and condensation is important for diagnosis and repair.

Cracked or Damaged Glazing

Skylight glazing can crack from impact (hailstorm, branch, other debris), thermal stress (particularly in older single-glazed units), or manufacturing defects. Cracked glazing is an immediate waterproofing problem in a flat or low-pitch skylight, where rain water will directly enter the crack. On pitched skylights, cracked glazing may not immediately leak vertically but allows water ingress at the crack and creates a structural weakness that can worsen with further thermal cycling.

Cracked single-pane glass in an older skylight is usually replaced with a modern double-glazed unit, which provides better thermal performance and is less susceptible to thermal cracking. Polycarbonate glazing — common in older skylights — tends to yellow with UV exposure, reducing light transmission, and can also crack or shatter with age and impact.

Failed Seals

The seals in a skylight system include the glazing seal (between the glass and the frame), the frame seals at corners and joints, and the weathering seals at the interface between the frame and the flashings. All of these seals have a finite service life and fail over time.

Glazing seals typically last 15–25 years depending on material quality and UV exposure. When a glazing seal fails, it may allow water into the glazing unit (causing fogging in double-glazed units) or allow external water to enter the frame. Failed seals around operable skylight mechanisms — hinges, operators, and opening edges — are a common source of leaks in venting skylights.

Frame Corrosion

Most modern residential skylight frames are aluminium, which is highly corrosion-resistant. However, older frames may be steel, and even aluminium can develop surface corrosion in coastal environments where the anodising or painted finish has been damaged. Corroded frames can compromise the seal between the frame and the glazing, and in severe cases can affect the structural integrity of the skylight unit.

In Coffs Harbour’s coastal environment, frame condition is worth monitoring — salt air affects unprotected aluminium surfaces over extended periods. If you’re seeing white powdery deposits (aluminium oxide) on your skylight frame, or rust staining on steel frames, it’s time for an assessment.

Failed Roof Integration

On older skylights — or on skylights that were poorly installed — the integration between the skylight flashing and the roof covering may not be done correctly. This is particularly common on tile roofs where the tiles around the skylight haven’t been properly cut, bedded, or replaced after the flashing was installed. When this is the case, water can enter at any of the four sides of the skylight where the tile edge meets the flashing, and the problem can be difficult to diagnose precisely without a close inspection.

Why Prompt Skylight Repair Matters

It’s tempting to monitor a small skylight leak and hope it resolves itself or doesn’t get worse. But there are good reasons to address it quickly:

• The damage compounds. Water entering through a skylight tracks along the roof structure before appearing at the ceiling. With each rain event, the moisture exposure of the structural timber increases. Wet timber degrades — it swells, can develop rot, and if the situation continues long enough, structural elements can be compromised.
• Mould establishes quickly. Mould spores are ubiquitous and germinate rapidly in warm, moist conditions. A Coffs Harbour summer is ideal for mould growth, and a persistently damp ceiling or wall cavity from a skylight leak can develop a mould problem within weeks of the leak beginning.
• Ceiling damage escalates. Water staining on a ceiling is a cosmetic problem. Water sitting above a plasterboard ceiling is a structural problem — plasterboard absorbs moisture, softens, and eventually fails. The cost of a ceiling repair is substantially more than the cost of the skylight repair that would have prevented it.
• The next storm makes it worse. A partial seal failure may not produce much water in a light rain, but can introduce a large volume in an intense event. Don’t discover the extent of the problem in a major storm.

Diagnosing Skylight Leaks

Correctly diagnosing a skylight leak requires understanding where water enters the building, distinguishing between leaks at the flashing, leaks at the glazing or frame, and condensation — and working out why the failure has occurred. This matters because the repair approach is different for each cause.

Our inspection process for a suspected skylight leak involves:

• Examination of the skylight from the roof — checking the condition of all flashings, the integration with the roof covering, and the condition of the frame and glazing
• Examination from inside (where accessible) — looking for evidence of water tracks, moisture in the ceiling space, or damage to the ceiling in the affected area
• Water testing in some cases — systematically applying water to specific areas to isolate the entry point
• Assessment of condensation potential — checking insulation in the sky shaft and ventilation conditions

We provide a clear diagnosis and repair recommendation before any work begins.

Skylight Repair Process

Flashing Repairs

Failed flashing around a skylight is the most common repair we carry out. This typically involves removing the failed sealant or flashing material, cleaning and preparing the surfaces, and applying new flashing material or sealant appropriately integrated with the roof covering. In some cases, the full flashing set needs to be replaced — where the original flashing has corroded or been incorrectly installed in a way that can’t be remediated by resealing.

Glazing Replacement

Cracked, damaged, or severely yellowed glazing is replaced with an appropriate unit. For older skylights with single-glazed or polycarbonate glazing, we typically recommend upgrading to a modern double-glazed glass unit at the same time — the thermal and performance improvement is significant and the incremental cost is modest.

Seal Replacement

Failed glazing seals and frame seals are cleaned out and replaced with new sealant rated for the application. On operable skylights, the seals around the opening mechanism are also checked and replaced if degraded.

Frame Repairs

Surface corrosion on aluminium frames can be treated and refinished. Severely corroded frames — where structural integrity is affected — may require the skylight unit to be replaced rather than repaired. We’ll advise based on the specific condition.

When Repair vs Replacement Is the Right Choice

Skylight repair is the right answer when the unit is structurally sound and the glazing is in good condition — a failed seal, a flashing problem, or a small crack can be repaired at a fraction of replacement cost. Replacement makes more sense when:

• The skylight is old and the glazing has significantly degraded (yellowed polycarbonate, failed double-glazed unit)
• The frame has extensive structural corrosion
• The skylight has been leaking for a long time and the surrounding roof area has been compromised
• The original skylight is poorly designed or incorrectly installed in a way that can’t be cost-effectively remediated
• The homeowner wants to upgrade to a larger, higher-performance, or venting model

We’ll give you an honest assessment of whether repair or replacement is the more sensible investment for your specific skylight.

Why Choose Roof Restoration Coffs Harbour

• 25 years of local experience — including extensive experience diagnosing and repairing skylight leaks in the Coffs Harbour environment.
• Licensed and insured — licensed roofing tradespeople with full insurances.
• Free inspections — no charge to diagnose and recommend.
• 10-year warranty — all repair work fully warranted.
• Correct diagnosis first — we find the actual cause, not just treat the visible symptom.

Book a Free Skylight Inspection

Got a ceiling stain near a skylight? Or noticed the skylight frame dripping during rain? Don’t wait for it to get worse. Call Nathan and the team at Roof Restoration Coffs Harbour on (02) 6638 9959 for a free inspection. If you’re thinking about installing a new skylight, visit our skylight installation page. For our full range of services, visit our services page.

A small skylight leak can become a major repair bill. Call (02) 6638 9959 and get it sorted today.

Preventing Future Skylight Problems

After a skylight repair, a little attention will extend the life of the repaired components and reduce the risk of recurrence:

• Have the skylight flashings included in your annual roof inspection — checking that sealant remains intact and no movement has occurred in the flashing since the repair.
• Keep the skylight glazing clean. Dirt and debris accumulate on the glass surface and can hold moisture against the frame seals, accelerating their deterioration. A gentle clean with mild detergent on an annual basis is all that’s needed.
• For operable skylights, test the opening mechanism and rain sensor regularly. A sensor that fails to close during rain defeats the purpose of having one.
• After any significant hail event or storm, do a visual check of the glazing for new damage before the next rain.

Choosing Between Repair and Replacement: The Cost Conversation

We’re often asked for a direct cost comparison between repairing and replacing a skylight. The honest answer is that it varies significantly with the skylight type, size, and the nature of the failure. As a general guide:

A flashing repair on a standard residential skylight is a relatively modest job — far less than a full replacement. If that repair adds 10–15 years of service life to a glazing unit that’s otherwise in good condition, the return is excellent. On the other hand, if the glazing is yellowed polycarbonate that’s transmitting half the light it once did, and the frame shows significant weathering, a replacement unit — while more expensive upfront — provides a new service life baseline and a significant improvement in performance. We’ll give you both options clearly priced so you can make an informed decision based on the condition of your specific skylight and your budget. There’s never any obligation.