When autumn rain and East Coast Lows sweep across the Mid North Coast, your roof has to shed a lot of water fast. Most of that job comes down to the sheeting, but there is a small, often-overlooked detail doing a huge amount of the work: flashing. When it is done well, you never think about it. When it fails, you get leaks.
So what is roof flashing, and why does this humble component matter so much? Here is a simple explanation of what it does and why keeping it in good condition protects your home.
The short answer: Roof flashing is thin metal that seals the vulnerable joins on a roof, around chimneys, pipes, skylights and in the valleys where two slopes meet, directing water safely back onto the roof. It fails through age, building movement, coastal corrosion or poor installation, and when it does, leaks usually show up as water stains below the join. Because flashing must be shaped, fitted and sealed precisely at height, repairs are best left to a licensed roofer.
What is roof flashing?
It’s the unsung hero of a watertight roof.
Where flashing is used on a roof
Flashing is typically thin metal that covers and seals the points where the roof meets something else, or where two roof surfaces join. These joins are the most vulnerable spots for water entry, so flashing directs water away from them and back onto the roof where it can drain safely. Without it, water would find its way straight into the gaps.
Around chimneys, pipes, skylights and in the valleys
You will find flashing in all the tricky spots: around chimneys, pipes and vents, along the edges of skylights, and in the roof valleys where two slopes meet and water channels down. Anywhere the roof surface is interrupted, flashing is what keeps it watertight.
Why flashing fails
Flashing does a tough job, and it does not last forever.
Age, movement, corrosion and poor installation
Over time, flashing can fail for a few reasons. Age and weather exposure break down sealants and materials. The natural movement of a building can loosen or crack flashing. Coastal salt air causes corrosion. And poor or rushed installation in the first place is a common culprit, as flashing needs to be fitted and sealed correctly to work. When it fails, flashing leaks often show up as water stains on the ceiling below the affected join.
Repairing and replacing flashing
The good news is that flashing problems are very fixable when caught early.
Why flashing work is best left to a licensed roofer
Roof flashing repair is precise work. It involves correctly shaping, fitting and sealing the flashing so water is properly directed away, and doing it safely at height. A licensed roofer or roof plumber has the skills and materials to repair or replace flashing so it lasts, rather than applying a quick patch that fails again at the next big downpour. If flashing is left too long, water can get into the structure and cause far more expensive damage. Because leaks often trace back to flashing, having it checked is a smart part of any roof repair or inspection. If you have spotted a leak, our guide on stopping roof leaks is a helpful next read.
Have Your Flashing Checked
If you have noticed water stains near a chimney, skylight or wall junction, your flashing may be the cause. IM Metal Roofing can inspect and repair flashing across Coffs Harbour and the Mid North Coast, keeping your home watertight.
Get in touch or call Aaren on 0432 175 102.
FAQs
Q: How do I know if my flashing is the problem?
A: Water stains or damp patches near a chimney, skylight, vent or where the roof meets a wall are classic signs of failing flashing. A licensed roofer can confirm the source and recommend a repair.
Q: Can flashing be repaired, or does it need replacing?
A: It depends on the condition. Minor issues can sometimes be repaired and resealed, while corroded or badly damaged flashing is better replaced. A roofer will assess it and recommend the most reliable, long-lasting fix.
Q: Is flashing a DIY job?
A: It is not recommended. Flashing needs to be shaped, fitted and sealed correctly to work, and it involves working at height. Poorly installed flashing is a common cause of leaks, so it is best left to a licensed professional.
