The Spring Drain MOT: 7 Post-Winter Checks Every London Homeowner Should Make

A British winter is harder on your drains than most homeowners realise. Freeze and thaw cycles, shifting soil and a whole autumn’s worth of decaying leaves all leave their mark, but the damage tends to stay hidden until the first heavy summer storm forces it into the open. The slow shower, the faint smell near the side return, and the leaves still wedged in the corner of the patio: these are easy to wave away once the weather warms up.

The good news is that you can get ahead of it in a single afternoon. What follows is a straightforward seven point spring drain check you can carry out yourself, with no special tools and no mess. We will show you exactly what to look for, when a bit of DIY is all you need, and when it is worth calling a professional to take a proper look below ground. The tone here is preventative rather than alarmist: most of these checks take minutes, and catching a small problem early is almost always far cheaper than waiting for it to surface on a wet weekend in July.

Why winter is hard on drains

Before the checklist, it helps to understand what the colder months actually do down there. Four things are usually at work:

• Freeze and thaw cycles. Water seeps into tiny cracks in the pipework, freezes, expands and slowly widens the damage. A hairline crack in November can become a real fault by April.
• Soil movement. Heavy rainfall and saturated ground shift the bedding around older clay and pitch fibre pipes, gradually pulling joints out of line.
• Stored debris. The leaves and grit that lodged in your gullies late last autumn have now broken down and packed together into a dense, water resistant plug.
• Heavier rainfall load. The wettest months push that debris deeper into the system, well beyond the reach of a set of DIY rods.

None of this is unusual and none of it is cause for panic. It simply means that spring, once the worst of the weather has passed, is the sensible time to look.

The 7-point spring drain MOT

Work through these in order. For each check we have flagged whether it is a job you can safely handle yourself or one worth handing to a professional.

1. Clear your gutters and downpipes

Start at the top. Look for moss caps, leaf dams and water stains on the render below the gutter line. This issue matters more than people think: an overflowing gutter dumps water straight at the foundation rather than carrying it safely into the drainage system. If you have a single storey extension and safe ladder access, this is a reasonable DIY job. For a two storey terrace, leave it to a professional. Falls from height are one of the most common causes of home maintenance injuries in the UK, and our team can clear gutters safely from the ground. You can read more on our gutter cleaning service page.

2. Walk-test every drain inside the house

Run every sink, bath and shower, plus the dishwasher, and time how long each takes to clear. A single slow shower is often the earliest warning sign of a partial blockage further downstream. If two or more fixtures on the same level are draining slowly, the problem usually sits past the appliance rather than being a simple hair clog. Repeat or stubborn blocked drains are worth investigating properly rather than living with.

3. Inspect outside gullies and channel drains

Lift each grate and clear away any visible debris, then run a hose into it for about thirty seconds. The water should disappear almost immediately. Standing water points to a blockage, while a smell suggests the problem sits further down the line. Channel drains across patios and thresholds are particularly prone to clogging with grit washed in over winter.

4. Check for foul smells around drain covers

Take a walk around the property after rain and have a sniff near every cover and gully. A persistent smell usually means a damaged seal, a dried out trap or a partial blockage. Pay particular attention to any odour that was not there in the autumn, as a new smell is a strong sign that winter has changed something below ground.

5. Look for sinking or depressed paving

Walk on your patios, paths and driveway, and press on kerbstones with your foot. Localised dipping along the line of a drain run is a classic early sign of a collapse underneath. It is easy to miss until it becomes severe, so do not ignore a patch that seems to be settling. You can read about the warning signs and what comes next on our collapsed drains page.

6. Test every toilet

Flush each toilet in turn and watch carefully. A slow refill, gurgling in a nearby bath or sink, or water rising before it drains away are all worth noting. Gurgling elsewhere when you flush usually points to a venting issue or a restriction further down the system rather than a problem with the toilet itself.

7. Walk the garden for boggy patches

Finally, walk the garden. Soft, sinking or unusually green patches over the line of a known drain run can indicate a leaking lateral pipe below. Clusters of small dark flies hovering over a single spot are another strong clue, as they are drawn to escaping waste. On a dry spring day, a patch of ground that stays damp deserves a second look.

When DIY rods are not enough

Plenty of minor blockages clear with a plunger or a set of rods, and there is no harm in trying these first. But some signs mean it is time to call in a professional rather than keep pushing:

• the same fixture blocks again within a few weeks
• several fixtures slow down at once, pointing to a shared problem downstream
• smells that survive a thorough clean
• visible cracks at an inspection chamber, or a cover that rocks when you step on it
• any sign of subsidence, a sinkhole, or vegetation suddenly thriving in one patch

In these cases, rodding often just pushes the blockage further along and buys you a fortnight at most. It is far better to find out what is actually going on.

Why a CCTV drain survey is worth it after a tough winter

A CCTV drain survey removes uncertainty about everything above. By feeding a camera through the system from an inspection chamber, our engineers can diagnose the issue exactly, with no exploratory digging. You get a clear record of the drain’s condition, which is invaluable for insurance and for future reference, and you find out whether a problem is something simple we can jet or descale or something that needs attention before it turns into a full collapse. After a hard winter it is one of the most cost effective things you can do, and every Drain 365 survey is carried out by fully trained engineers to NADC standards, with the reassurance of our £5 million public liability cover.

What we tend to see across London and the Home Counties at this time of year

Spring brings a fairly predictable set of problems. We see root intrusion in the older clay drains common to many Hertfordshire properties, surface water gullies collapsing under load on London’s Victorian terraces, and freeze damage on the pitch fibre runs found in a lot of post war housing across Bedfordshire and Buckinghamshire. Wherever you are in North London or beyond, the pattern is the same: winter does its damage quietly, and spring is when it shows.

A few checks now, big savings later

Seven checks, an afternoon of your time, and a much smaller chance of an expensive emergency when the summer storms arrive. If everything came up clear, brilliant: put a note in the diary to look again in the autumn. If anything made you hesitate, do not wait for it to get worse.

Book a CCTV survey or talk through what you found with our friendly team. Call us free on 0800 699 0922 or fill in our contact form, and we will get back to you as soon as we can. For anything urgent, our 24/7 emergency line is open every day of the year at 07534 199 005.