Commercial Drainage Kingston upon Thames | What You Owe

Your restaurant on Eden Street is failing its environmental health inspection because of FOG. Your Norbiton HMO has a blocked shared stack and three tenants are complaining. Your commercial unit in Kingston Town Centre has a gully that hasn't been touched since the last tenant left three years ago. These aren't hypotheticals. They're the calls we get every week.

Commercial and landlord drainage is different from a domestic blocked drain, and not just in scale. The obligations are different, the liability is different, and the way you should be thinking about maintenance is completely different. A homeowner can reasonably wait until something goes wrong before calling anyone. A landlord or business owner who does that is gambling with their tenants' habitability, their food hygiene certificate, and in some cases their insurance cover.

So here's an honest run-through of what you actually owe, what you should be doing, and where people go wrong.

The grease trap problem, and why it's worse than you think

If you run any food operation in Kingston, whether that's a full kitchen on Clarence Street, a café in Surbiton, a takeaway in Tolworth, or a deli in Thames Ditton, you almost certainly have a grease trap. Or you should have one.

Fats, oils and grease (FOG) don't behave in a drain the way water does. Hot grease runs freely. The moment it cools in contact with the pipe wall, it solidifies and sticks. Every service produces more. The layer builds. Eventually you get a FOG blockage that can be genuinely spectacular in scale, and it's almost never cheap to clear because no amount of jetting alone removes hardened fat from a length of 100mm pipe without some serious descaling work.

A properly installed grease trap intercepts FOG before it enters the drain run. The food waste and grease settle out. The relatively clean water passes through. That's the theory. The practice is that grease traps need regular emptying and cleaning, and most operators leave it far too long.

How often? It depends on your throughput, but as a rough guide:

• A busy Kingston restaurant might need the trap emptied every four to six weeks.
• A café or sandwich bar, probably every two to three months.
• A low-volume operation, quarterly at minimum.

If you can't remember the last time your trap was serviced, it's overdue. An overloaded trap stops intercepting FOG and just becomes an obstacle in the drain run. At that point you're worse off than if you had no trap at all.

Environmental health officers in Kingston upon Thames know what a neglected grease trap looks like, and it can contribute to a failed inspection. Thames Water also has enforcement powers under the Water Industry Act 1991 for FOG discharges that cause problems in the public sewer. You don't want a notice under that Act.

High-pressure water jetting will clear a FOG blockage. Jetting plus descaling will do a more thorough job. But neither replaces a properly maintained trap. If you haven't got one, or yours is undersized for your operation, that's a conversation worth having before the blockage happens.

Planned maintenance contracts versus reactive calls

There's a common mindset among small business owners and landlords that goes: if it's working, leave it alone. I understand the logic. Cash flow is tight, and a drain that isn't blocked isn't a cost centre.

Here's the problem. Drainage doesn't usually fail suddenly. It fails slowly, then all at once. By the time a drain is backing up into your kitchen or your tenants' bathroom, you're in emergency territory, and emergency calls cost more than planned ones, at any hour.

A commercial drainage maintenance contract changes the calculation. We schedule regular CCTV drain surveys so you can see what's actually happening inside the pipework before it becomes a crisis. Regular jetting keeps grease accumulation, silt and debris from reaching blockage levels. Gullies and manholes stay clear. You know what's there.

For landlords with HMOs in Norbiton, Canbury or Kingston Gate, shared drainage is particularly worth watching. Multiple households sharing a single stack or a single drain run means multiple sources of grease, wet wipe accumulation (yes, the ban is coming, but the pipes are still full of wipes that went in before it), and sanitary waste. The more households, the faster things build up. An annual CCTV survey and a jetting visit or two per year is genuinely cheap compared to an emergency call at 11pm because the ground-floor flat's toilet is backing up.

For commercial landlords, there's also the question of what the previous tenant left behind. A CCTV survey before a new tenant takes occupation tells you the condition of the drains, documents it, and gives you a baseline for any dispute later about who caused damage. That alone is worth the cost of the survey.

Landlord obligations: what the law actually says

This is the bit people get wrong most often, so I'll be specific.

Section 11 of the Landlord and Tenant Act 1985 requires landlords of residential properties to keep in repair and proper working order installations for sanitation, including pipes, drains and sewers. That obligation applies to drains within the boundary of the property. Drains that become shared public sewers further down the run are Thames Water's responsibility, but everything on your side of the boundary is yours.

For commercial leases it's different, and the specifics depend entirely on the lease terms. Many commercial leases put drainage maintenance on the tenant under the repair covenant. But that doesn't mean you as a landlord can ignore the structure. If drain runs are buried in the fabric of the building, or shared between multiple units, the position can be more complex. If you're not sure where your responsibility ends and your tenant's begins, the lease wording and a property solicitor are the places to go, not a drainage company.

What I can tell you from the field is that arguments about who's responsible for what almost always happen after a blockage, not before. Getting a baseline CCTV survey done, keeping records of what maintenance has been carried out, and having a clear understanding of the drain layout of your property puts you in a much stronger position in any dispute.

For HMO licence holders in Kingston upon Thames, the council's licensing conditions typically require that the property is kept in a good state of repair, and drainage is part of that. A serious blockage that makes the property uninhabitable even temporarily is a licensing issue, not just a maintenance one.

CCTV surveys: what they actually show you

A CCTV drain survey isn't just for finding blockages. That's the least interesting thing it does.

Push a camera through a drain run in a Victorian terrace in Ham or a 1930s semi in Coombe Vale, and you might see:

• Root ingress from trees or shrubs growing over the pipe
• Cracked or collapsed sections, common in older clay pipe systems
• Displaced joints where pipes have shifted, often from ground movement or tree root pressure
• Incorrect falls where pipes have sagged and silt accumulates
• Illegal connections where surface water has been connected to a foul drain or vice versa
• Evidence of FOG accumulation that hasn't yet caused a blockage but will

For a landlord buying a commercial or residential investment in KT1 or KT2, a pre-purchase CCTV survey is one of the most useful bits of due diligence you can do. A collapsed section of 150mm pipe under a car park costs a lot to repair. Knowing about it before you exchange is considerably cheaper.

For an existing landlord or business owner, an annual survey gives you documented evidence that you're maintaining the property properly. If a tenant causes damage through misuse (and it happens), you have the before-and-after to show it.

Root cutting and descaling: the underused options

Roots in drains are very common in Kingston upon Thames. Coombe Hill, Coombe Vale and Kingston Vale have substantial mature tree cover. Hampton Wick and Teddington have streets lined with trees whose roots have been working their way into clay pipe joints for decades. Even newer PVC pipe runs can be compromised if a joint fails.

Root ingress starts small. A hairline crack, a root tip finding its way in, more roots following. Over time you get a root mass that catches toilet paper, wipes and grease, and you end up with a recurring blockage that jetting clears but doesn't cure. The roots grow back.

Root cutting removes the root mass from inside the pipe. It's not a permanent fix if the pipe is cracked, because the crack remains and the roots will return. But combined with a drain liner, it can give you a repaired, sealed pipe that roots can't penetrate. That's a long-term solution rather than a recurring maintenance cost.

Descaling is the equivalent for limescale and FOG. High-pressure jetting breaks it up. A descaling head removes it more thoroughly. For commercial kitchen drains that have been in service for years without proper maintenance, descaling before regular jetting starts gets the system back to a proper baseline.

When a liner is the right answer

I spend a lot of my time arguing against digging things up unnecessarily. A drain liner installs from inside the pipe. No excavation, no disruption to a car park, no lifting of kitchen flooring, no closure of a commercial unit while work takes place.

The liner is impregnated with resin and inverted or pulled into place, then cured. The result is effectively a new pipe inside the old one. It bonds to the host pipe, seals cracks and joints, and stops root ingress. On remedial work like this, we back it with a 20-year guarantee.

For commercial properties in Kingston Town Centre where any excavation would require a road closure or planning consent, or for a rental property where a tenant is in occupation, the no-dig approach isn't just convenient. It's often the only practical option.

Not every pipe is reliably lineable. A completely collapsed section usually needs excavation. But a cracked, root-infiltrated or displaced-joint pipe that's still fundamentally in its original position is a good candidate. A CCTV survey tells you which situation you're in.

What to do next

If you've read this far and you're thinking about a property in the KT postcodes, the sensible starting point is a CCTV survey. It tells you what you've got. From there, maintenance requirements and any repair work become obvious rather than guessed at.

Drainsco covers Kingston upon Thames and the surrounding KT postcode areas. Engineers are available 24/7 for emergencies, but planned work is priced and scheduled in advance with a clear price before we start. There's no call-out fee. If you want to talk through a maintenance contract for a commercial property or a portfolio of rentals, a phone call is the right place to start.