Mr. Clog Plumbing
Box Gutter Leak Repairs & Replacement Sydney
Water through the ceiling in heavy rain, near a parapet wall or where two roofs meet? A leaking or overflowing box gutter is a common cause. We find the leak, then repair or replace the box gutter.
No surprise bills: $0 call-out and a fixed price before any work starts.
Our guarantee: 12 months on our workmanship, in writing. What it covers
About This Service
A box gutter is a gutter built inside the roof line, between two sections of roof or behind a parapet wall. You see them on terraces, semis, apartment blocks, and extensions joined to an older roof. Because a box gutter sits over the inside of the building, when it leaks or overflows, the water comes into the ceiling and walls instead of falling outside. The usual causes are a rusted gutter base, failed joints, a blocked outlet or rainhead, an outlet too small for the roof it drains, and an overflow that's missing or blocked. We find which it is, clear and repair what can be repaired, and replace the box gutter when it has rusted through. If you're making an insurance claim, we can write a plumbing report on what failed. You get a fixed price before we start, and 12 months on our workmanship.
What’s Included
- Box gutter leaks found
- Blocked outlets, sumps and rainheads cleared
- Leaking joints repaired
- Rusted box gutters replaced
- Overflows checked
- Plumbing reports for insurance claims
- Fixed price quoted before we start
- 12 months on our workmanship
Fixed price quoted before we start. $0 call-out fee.
Ready to book?
(02) 9139 8945 — available 24/7Why Box Gutters Leak Inside
A rusted base
Leaves and silt sit wet in the bottom of the gutter, and the steel rusts through from the top.
Failed joints
Joints along the box gutter and at the outlet open up over time.
A blocked outlet or rainhead
When the outlet blocks, the gutter fills like a bath. If it can't overflow outside, it overflows inside.
No working overflow
A box gutter needs a way for water to escape outside when the outlet can't keep up. If there isn't one, or it's blocked, heavy rain ends up in the ceiling.
Where it meets the wall
Along a parapet or a higher wall, the flashing between the gutter and the wall can let water in.
Repair or Replace?
Repair
A blocked outlet, a leaking joint or a small damaged area can usually be fixed in place.
Replace
A box gutter that has rusted through along its base, or keeps leaking after repairs, needs replacing. It's also the time to look at whether the outlet and overflow are big enough for the roof.
Keeping a Box Gutter Working
Keep it clear
Leaves sitting in a box gutter block the outlet and rust the base. Overhanging trees mean it needs checking more often.
Check the outlet before storm season
Make sure the outlet, sump or rainhead is clear and the overflow isn't blocked.
Act on the first ceiling stain
A stain that appears after heavy rain and dries out is an early warning. It's cheaper to fix the gutter than the ceiling.
How It Works
Our Process
Find the leak
Gutter base, joints, outlet, overflow and where it meets the walls.
Fixed price
Repair or replace, explained before any work starts.
Repair or replace
Outlet cleared, joints repaired, or the box gutter replaced.
Water test
Water run through to check it drains and doesn't leak.
Related Pages
Common Questions
FAQs
What is a box gutter?
A gutter built inside the roof line, between two roofs or behind a parapet wall, rather than hanging off the edge of the roof.
Why does my ceiling only leak in heavy rain?
That often points to a box gutter overflowing: the outlet can't keep up and there's no working overflow, so water comes inside. It can also be a rusted base or joint that only leaks when the gutter fills.
Can a box gutter be repaired, or does it need replacing?
Blocked outlets, leaking joints and small damaged areas can often be repaired. A box gutter rusted through along its base needs replacing.
Do you check the overflow?
Yes. We check the box gutter has a working overflow, and that the outlet suits the roof it drains.
Can you write a report for my insurance claim?
Yes. We can write a plumbing report on what failed and what we repaired.
How much does box gutter repair cost?
It depends on what's failed. We give you a fixed price before we start, with a $0 call-out fee.
What Sydney Customers Say
We recently used Mr Clog Plumbing for our granny flat in Guildford and couldn't be happier with the service. Everything was handled professionally from start to finish, with great communication and workmanship…
Absolute legend. Turned up on time, sorted the problem quickly and didn’t charge a fortune. Super easy to deal with and cleaned up after the job too. Will definitely be using him again and would happily recomme…
Turned up on time and honest service, couldn’t ask for much more.
Get a Quote for Box Gutter Repairs
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