Clearing blocked drains across Dublin since 1968 — day or night.
Skip to content Clearing blocked drains across Dublin since 1968 — day or night.
A sewage smell that keeps coming back means something is wrong underground where you cannot see it. We trace the exact source with CCTV, smoke testing and dye testing, then fix it so the smell stops for good.
Since 1968
Over 35 years on Dublin drainage
24/7 call-outs
Answered any hour, every day
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All enquiries are reviewed by our team before a consultation is confirmed.
There is always a reason a drain smells. These 8 cover almost every case we are called out to.
Dry trap
An unused drain loses its water seal, letting sewer gas rise into the room.
Cracked pipe
Drain still flows, but gas escapes through the crack. No blockage shows.
Failed manhole seal
Gas rises up through the cover or the ground around the manhole.
Blocked vent
The vent cannot release pressure, so gas pushes back through indoor traps.
Cross-connected pipes
A waste pipe joined to the wrong drain, often after an extension or renovation.
Fat or debris in the line
Trapped waste breaks down and gives off gas. Worse in warm weather.
Grease trap overflow
A neglected trap overflows into the kitchen drains during a busy service.
Shared drainage
The source sits in another unit and travels through shared pipes and manholes.
When a quick clean stops working, the smell needs finding.
The source sits below the trap.
A break or leak underground, still flowing.
Pressure change, a failing vent or a crack under load.
Often a cracked pipe, missing trap or misconnection.
A hygiene and reputation risk. Needs tracing fast.
Shared drains. Smoke testing finds the exact entry.
A camera inside the pipe shows the crack, break or build-up releasing the gas. It is our full CCTV drain survey, focused on tracing the smell.
We pump non-toxic smoke through the drainage. It escapes from any fault it reaches, showing on the surface exactly where gas is getting into the property.
We run coloured dye through specific drains and follow where it comes out. It shows misrouted pipes and connections joined to the wrong drain.
We price each job after assessing the site, so you pay for what your investigation actually needs.
Tell us about the smell and the property. We assess the site, pick the right method, and confirm the price before any work starts.
A three-bed semi with two manholes is a smaller job than a 20-unit commercial block.
CCTV on its own, or CCTV with smoke and dye testing. Each one added takes more time.
Simple faults like a dry trap or a broken seal are fixed on the visit. Bigger repairs are quoted on their own.
Commercial kitchens, basements and shared drains take longer to trace than a standard house.
The questions homeowners and business owners ask us most before booking.
The most common reason is a dry trap. When a sink or floor drain goes unused, the water seal that keeps sewer gas out dries up and the smell comes into the room. Run water down every drain to refill the traps. If it stays, the cause is usually a cracked pipe, a failed manhole seal or a blocked vent, which needs tracing.
A sewage smell that comes and goes usually points to a pressure problem in the drainage. The three usual causes are a blocked vent pipe, a crack that only leaks gas under load, and a trap being siphoned dry by another fixture. Smoke testing is the most reliable way to find an intermittent smell, because the fault shows the moment the smoke reaches it.
If the drain flows freely but still smells, the cause is usually structural: a cracked pipe, a displaced joint or a failed seal at the manhole. Water still passes through, but gas escapes through the break, so cleaning will not fix it. A CCTV survey shows the exact location of the defect so it can be repaired.
A persistent sewage smell should not be ignored. Sewer gas contains hydrogen sulphide and methane, which are harmful in high concentrations. In a normal home the levels are usually low, but the smell means gas is getting in through a fault in the drainage. Tracing and fixing that fault clears both the smell and the source.
The cost of a drain odour investigation depends on the size of the property, how many methods it takes to trace the source, and whether the fix is included. A standard house costs less than a multi-unit or commercial site. We assess the property first and confirm the price before any work starts, so there are no surprises.
An odour investigation is usually done in a single visit. The time depends on the size of the property, the number of access points and how many methods are needed to trace the source. Commercial and multi-unit sites take longer than a standard house. We confirm the likely timeframe before we start.
Not once the real source is repaired. We trace the fault, fix it, then test again to confirm the smell has gone. A pipe reline or a new seal is a permanent repair. If the cause was simply a dry trap, we show you which drains to run water down now and again to keep the seal topped up.
For a sewage smell in the house, call a drainage contractor with odour tracing equipment. A plumber can check the traps and pipework inside the house, but if the source is underground or in the outside drainage, it takes CCTV, smoke testing or dye testing to find. Call Davis Drain on (01) 849 1706 and we will work out whether the problem is inside or outside.
Tell us about the smell and the property. We assess, recommend the right method, and come back with a price.
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