Box gutter repairSydney
Box gutters sit inside the roof line, so when they fail the water ends up in your ceiling. We repair, reline and rebuild box gutters with the fall and overflow they should have had from day one.
- Terraces, semis, flat roofs and commercial
- Sumps, rainwater heads and overflows added
- Built to AS/NZS 3500.3 box gutter requirements
Why box gutters leak
A box gutter is a wide, flat-bottomed gutter concealed behind a parapet or between two roof slopes. They are common on Sydney's inner-city terraces and on commercial and industrial roofs. Because they are nearly flat, any sag in the supporting timber creates a pond. Standing water finds laps and rivet holes, and rust follows.
The more serious problem is overflow. An eaves gutter that overflows spills outside the building. A box gutter that overflows spills inside. That is why the plumbing standard requires box gutters to have a minimum fall, a sump or rainwater head at the outlet, and a dedicated overflow.
Repair options
Where the gutter is structurally sound, joints can be re-made and the gutter relined with a new steel tray or a membrane system. Where the base has rusted or the support has sagged, the gutter is rebuilt: new support, a single-length tray where possible to remove joints, a properly sized sump and an overflow that discharges where you can see it.
For shared box gutters between terraces, we can quote both owners together so the whole run is fixed at once.
What does box gutter repair cost?
| Job | Guide price (inc. GST) |
|---|---|
| Box gutter repair or reline | $800 – $3,000 |
| Box gutter replacement | $120 – $250 per metre |
| Add sump, rainwater head or overflow | $450 – $1,200 |
Indicative Sydney ranges only. Your quote is a fixed price based on your property. Full details in the gutter repair cost guide.
From first message to finished gutter
No sales visit and no vague hourly rates. You know the price before anyone climbs a ladder.
Send the details
Use the quote form. A sentence about the problem and your suburb is enough to start.
Get a fixed price
Simple jobs are quoted from your description and photos. Larger ones get an on-site measure.
Work is booked in
Pick a day that suits. Urgent leaks are made safe first, then repaired properly.
Checked and cleaned up
Gutters are water tested, old materials are taken away and you get photos of the finished job.
Box gutter repair: common questions
Can a box gutter be repaired without replacing it?
Often, yes. If the tray and its support are sound, leaking joints can be re-made or the gutter relined. If the base is rusted through or the gutter holds water because the structure has sagged, replacement is the reliable fix.
How much fall should a box gutter have?
Under AS/NZS 3500.3 a box gutter needs a minimum fall of 1:200 toward the outlet, and must discharge to a sump or rainwater head with an overflow. Many older box gutters in Sydney were built with little or no fall.
Who pays for a shared box gutter between terraces?
A box gutter on the boundary serving both roofs is normally a shared responsibility. It is best repaired as one job with costs split by agreement between the owners.
Box gutter repair across Sydney
Available in every region we cover. Choose your area for local information.
Ready for a fixed-price gutter quote?
It takes about a minute, and there is no obligation.