Roof Flashing Repair in Townsville: Common Problems and How to Fix Them

Damaged roof flashing can let rainwater into your home, leaving you with ceiling stains, wet insulation and even mould. The sooner you deal with the problem, the less chance water has to cause further damage. But the fix depends on what’s wrong. A small gap around a roof joint may only need fresh sealant, while rusted, bent or poorly fitted flashing may need replacing.

In this guide, we’ll take you through common roof flashing problems, explain what causes them, and show you how a licensed roof plumber in Townsville can fix them and help keep your home dry.

TL;DR

• Salt-Air Corrosion: Salt and moisture break down flashing’s protective coating, leading to rust, holes and roof leaks. Rinse accessible areas every few months and replace deeply corroded flashing.
• Lead and Colorbond Corrosion: Contact between lead and Colorbond can cause galvanic corrosion. Replace lead flashing with a compatible material or install a suitable insulating barrier.
• Wind-Lifted Flashing: Strong winds can loosen screws, lift flashing and let rainwater into your roof. Secure loose sections and replace bent or torn metal.
• Cracked or Missing Sealant: Townsville’s heat and UV exposure can make sealant shrink, crack or peel. Remove damaged sealant and apply a fresh, UV-resistant roofing sealant.
• Poorly Installed Patio Flashing: Flashing that doesn’t extend behind the wall cladding can let water into the wall cavity. Have a roof plumber check its position and refit or replace it.
• Leaking Flashing Around Vents and Skylights: Cracked rubber vent boots, damaged sealant and loose metal flashing can let rainwater into your roof cavity. Inspect visible areas and repair damaged components.

Roof Flashing Problems and How to Repair Them

Most flashing problems on Townsville roofs trace back to the climate. Salt air corrodes the metal, cyclone winds lift anything that isn’t fixed down properly, and the sun dries out sealant until it cracks. How it can be fixed depends on which one you’re dealing with. 

Corroded Flashing from Salt Air

Townsville’s coastal air carries salt inland, where it settles on your roof flashing. Salt attracts moisture and keeps it against the metal. Over time, this moisture and salt can break down the protective paint or metallic coating on the flashing, exposing the bare metal underneath. The exposed areas can then start to rust. As the corrosion spreads, it can eat through the flashing and create holes that let rainwater into your roof cavity. 

What to do about it:

1. Wash away salt buildup: Rinse accessible roof areas with fresh water every few months using a garden hose to remove salt and dirt before they damage the protective coating.
2. Look for signs of rust: From the ground, use binoculars to look for brown or orange streaks running down the roof sheets below the flashing. Also check for peeling paint or discoloured metal around visible roof edges and joints. If you spot any of these signs, arrange an inspection with a licensed roof plumber. They can check how far the corrosion has spread and whether the flashing needs cleaning, repair or replacement. 
3. Replace rusted flashing: If the flashing has deep pits, thin patches or holes, it needs replacing. A roof plumber will remove the old flashing and its fixings, cut a new piece to match the roof profile, and secure it in place. They’ll also seal the joints to stop rainwater from getting underneath. 

Lead Flashing Corroding a Colorbond Roof

When two different metals, such as lead flashing and Colorbond steel, come into contact in the presence of moisture, they can react and cause galvanic corrosion – one metal starts to break down when it touches a different metal in wet conditions. Over time, this reaction can damage the protective coating on the Colorbond steel, exposing the metal underneath to rust. 

What to do about it:

1. Look for signs of damage: Use binoculars and look for brown streaks, rust spots or discoloured patches on the Colorbond sheets below any visible lead flashing. These are early signs of corrosion. 
2. Replace the lead flashing: The best long-term fix is to remove the lead flashing and replace it with a material compatible with Colorbond steel. This prevents the two metals from reacting when they come into contact with moisture. A roof plumber can select a suitable replacement based on the roof’s design and the joint that needs sealing.
3. Isolate lead that cannot be removed: Sometimes, lead flashing is built into a brick wall or tucked beneath other roofing materials, making removal difficult. A roof plumber can install a suitable separation layer, such as a purpose-made insulating membrane or barrier, between the lead and Colorbond. This prevents direct contact between the two metals. The right solution depends on how the flashing is installed.
4. Arrange follow-up inspections: If lead flashing remains on your roof, have the surrounding Colorbond checked regularly, especially after the wet season. A roof plumber can look for rust spots, small pits and damage to the protective coating before the corrosion spreads.

At 1Touch Plumbing, we can help with all this. Our QBCC-licensed roof plumbers will inspect your roof and recommend the right solution. We can replace the lead with compatible flashing or install a suitable barrier where removal isn’t practical. We also offer follow-up roof maintenance to check for new signs of corrosion and catch any damage before it spreads. 

Flashing Lifted by Storm Wind

Townsville falls within Wind Region C, so roofs here need to withstand strong winds. During a storm, strong gusts put upward pressure on roof flashing, particularly around ridges, roof edges and wall joints. If the flashing isn’t secured properly, loose or missing screws can make it easier for the metal to lift, bend or tear away. Once the flashing pulls away from the roof, it allows wind-driven rain to enter. Water can then reach your ceiling, walls and roof insulation, causing further damage. 

What to do about it:

1. Wait for the storm to pass: Don’t approach the roof during strong winds or heavy rain. Wait until the weather clears before checking for damage.
2. Look for lifted flashing: From the ground, check the roof ridges, edges and wall joints. Look for metal hanging loose, raised edges or visible gaps. You can also check inside for fresh ceiling stains or damp patches that suggest rain has entered through the damaged flashing.
3. Tighten accessible loose screws: If the flashing is at a low level and you can reach it safely without stepping onto the roof, check whether any screws have come loose. Use a screwdriver with the correct bit to tighten them. Stop once the flashing sits firmly in place. Don’t overtighten, as this can damage the metal or rubber washer.
4. Replace bent or torn flashing: Tightening screws won’t fix metal that’s bent, creased or torn. A roof plumber will need to remove the damaged section, cut a replacement to fit and secure it properly.

Cracked or Missing Sealant

Sealant is a waterproof material used to close small gaps where roof flashing meets other surfaces, such as walls, vents and skylights. It helps stop rainwater from getting underneath the flashing and entering your roof. However, Townsville’s strong UV rays and storms can wear it down over time. The heat dries out the sealant, causing it to shrink, crack or pull away from the metal. Once this happens, water can seep through the gaps and into your roof cavity. 

What to do about it:

1. Check for damaged sealant: Use binoculars and look for cracks, peeling edges or gaps around roof joints and penetrations from the ground. 
2. Remove the old sealant: If the damaged joint is safely accessible without climbing onto the roof, use a putty knife to remove loose or cracked sealant. For elevated roof joints, let a roof plumber handle the work.
3. Clean and dry the surface: Brush away dirt, leaves and loose material from the joint. Wipe the area clean and let it dry completely. New sealant won’t stick properly to a dirty or damp surface.
4. Apply fresh roof sealant: Choose a UV-resistant silicone or polyurethane sealant made for roofing and suitable for Colorbond or metal flashing. Cut the nozzle at an angle and place the tube in a caulking gun. Slowly squeeze the trigger to apply an even line of sealant along the gap. Make sure the gap is fully covered, then smooth the sealant along the joint with a gloved finger, and leave it to cure. 
5. Check the sealant every year: Look for new cracks, peeling edges or gaps around accessible roof joints. Replace damaged sealant before rainwater gets underneath. 

Poorly Installed Flashing at Walls and Patios

Where your patio roof meets your house, flashing covers the joint between the two roofs to stop rainwater from getting behind the connection and entering your home.

The flashing should extend partly behind the wall cladding (the outer material covering your wall). This allows rainwater running down the wall to flow onto the flashing and then onto the patio roof, rather than getting trapped behind it. If the flashing sits against the wall or doesn’t extend far enough behind the cladding, water can seep into the wall cavity and cause leaks.

Sometimes, installers apply silicone along the gap between the patio roof and the house wall instead of fitting the flashing correctly. This may keep water out for a while, but silicone can dry out and crack over time, allowing rainwater to seep through the joint and into the wall cavity.

What to do about it:

1. Look for signs of a leak: From the ground, examine the area where the patio roof meets your house. Water stains, peeling paint or damp patches on the wall can indicate that water is getting behind the flashing.
2. Check the sealant: See whether a thick layer of silicone has been used to cover the gap between the patio roof and wall. This may mean the installer used sealant instead of fitting the flashing correctly. Have a roof plumber inspect the joint if you notice this.
3. Inspect for loose or damaged flashing: Use binoculars from the ground to spot metal that appears lifted, bent or hanging away from the wall.
4. Have the flashing installation checked: Our roof plumbers at 1Touch Plumbing can inspect how the flashing meets the wall cladding and check whether it extends far enough behind it to direct rainwater onto the patio roof. If it is poorly fitted or loose, they can remove the affected section, position it correctly and secure it in place. If the flashing is damaged, they may need to replace it.

Leaking Flashing Around Vents and Skylights

Vent pipes and skylights leave openings in your roof, so the areas around them need proper flashing to keep rainwater out. Around a vent pipe, the flashing has a metal base that sits against the roof and a rubber boot that fits around the pipe to seal the gap. Around a skylight, metal flashing runs along the edges of the frame and directs rainwater away.

Over time, Townsville’s heat and strong UV rays can make rubber boots brittle and cause sealant around the joints to crack. Strong winds can also loosen or bend metal flashing. Once these parts become damaged, gaps can form and let rainwater into your roof cavity.

What to do about it:

1. Look for damage around vent pipes: From the ground, check for visible cracks or splits in the rubber boot around the pipe. If you notice damage, the boot may need replacing. 
2. Check the sealant around skylights: Look for cracked, peeling or missing sealant around the skylight frame from the ground, using binoculars if needed. Damaged sealant can let rainwater seep underneath the flashing. 
3. Look for loose or damaged flashing: From the ground, check for lifted edges, bent metal or visible gaps around the vent and skylight. If you spot any of these signs, the flashing may need replacing.

If you notice any of these problems, have our licensed roof plumber at 1Touch inspect the area and recommend the right repair. We’ll replace damaged rubber boots, reseal leaking joints or repair and replace loose or damaged flashing to keep rainwater out of your roof.

Final Thoughts 

Repairing your roof flashing might look like a quick job, nothing a tube of sealant and a few screws can’t handle. But that’s exactly why so many DIY repairs give way once the wet season arrives. If the new metal reacts with your roof, the sealant doesn’t suit the flashing, or there aren’t enough fixings to keep it down in a cyclone, the leak comes straight back, often with corrosion on top. 

Then there’s also the risk of climbing onto a metal roof in the first place, which can be slippery and hot underfoot. So unless you’re confident up there and know what you’re looking for, it’s a job worth leaving to someone who does it every day.

At 1Touch, we’re a QBCC-licensed roof plumber Townsville homeowners call to trace the leak to its cause first, so the reseal, refix or replacement we do suits your roof and stays put through Wind Region C weather. 

Book a roof inspection before the wet season, and we’ll fix what needs fixing while the weather’s still on your side.

FAQs

How much does roof flashing repair cost?

Smaller jobs, such as resealing a small gap or securing a loose section, cost less. More involved repairs, such as replacing a damaged section of flashing or repairing several leaking joints, cost more. The final price depends on the type of flashing, extent of damage, roof height, access and materials required. Contact our team for a quote based on your roof’s condition and the work needed.  

How long does roof flashing last?

Roof flashing can last anywhere from 15 to 100 years, depending on the material, installation and maintenance. Lead and copper can last over 60 years, while Colorbond and galvanised steel typically last 15–40 years. But, remember that in Townsville, the salt air, humidity and strong UV exposure can shorten its lifespan. 

Does insurance cover damaged roof flashing?

Home insurance may cover flashing damage caused by a sudden insured event, such as a storm, cyclone or falling tree. However, most policies exclude damage caused by gradual deterioration, rust, corrosion or poor maintenance. Check your policy to see what’s covered and which exclusions apply. 

What type of flashing is best for a Colorbond roof?

The best option is a genuine Colorbond or Zincalume steel flashing, as these materials are compatible with the roof and reduce the risk of corrosion. Lead-free flexible flashing may also suit certain roof joints. The right choice depends on the roof design and the area being sealed. Our roof plumbers can recommend and install a suitable option.