Shower drain unblocking for hair and soap scum

Why a shower drain gets blocked so quickly

Every day a mix of hair, soap, shampoo, dead skin and limescale goes down the shower drain, yet the pipe itself is narrow. In most bathrooms the water runs through a PVC pipe of around 40 millimetres into the shared waste pipe or the soil stack. That's plenty for water, but a clump of hair and soap residue catches in it easily.

Then there's the fall. A horizontal waste pipe needs to slope slightly – the usual rule of thumb is about a centimetre per metre. If a pipe has been laid flatter, or sags under a heavy tiled floor, the water flows too slowly to carry dirt with it. The dirt settles, and every shower adds another thin layer.

Hair and soap scum

Most bathroom blockages start at the trap under the grate. Hair catches on its rim. Soap combines with the lime in hard tap water to form soap scum, a sticky grey deposit that holds the hair in place. Conditioner, bath oil and exfoliating beads make that layer even tougher. After a few months, the opening is only a fraction of its original size.

Renovation debris

In a new bathroom we see a different pattern. Tile adhesive, grout or plaster gets rinsed down the drain during the building work and then sets hard in the pipe. The design plays a part too. A walk-in shower with a flat linear drain often has a smaller water seal and a narrower passage than a conventional shower drain, and the pipe underneath is sometimes laid in the floor screed with very little fall.

Bath blocked but the shower's fine

A bath has its own waste: a plug, an overflow and a trap, which usually sits behind the bath panel. Hair gets caught around the plug mechanism and in the connection to the overflow. If only the bath is slow to empty, the cause is almost always in that short section, not further down the pipe.

Where is the blockage? How to read the signs

Before you start unblocking a shower drain, it helps to know where the blockage is. The way the water behaves tells you a lot:

• Only the shower drains slowly. The blockage is almost certainly in the drain itself or the trap.
• The shower and washbasin are both slow. The problem is in the pipe they share.
• Water rises in the shower when the toilet is flushed. The blockage is further down, in the shared waste pipe, the soil stack or the underground drain beneath the house.
• The drain gurgles or smells of sewage. Air is being forced back up because the water can't drain away freely, or the trap has dried out.

That third sign is the one to take seriously. In many homes the shower drain is the lowest point of the drainage on that floor, so if the pipe further along fills up, that's where the water comes up first. In a block of flats, a blocked soil stack affects the flats on the lowest floors, while residents higher up often notice nothing.

Doing it yourself: what's safe and what isn't

Safe to try yourself

If the blockage is just below the grate, there's a lot you can do yourself:

1. Remove the grate and pull out any visible hair with a gloved hand or a plastic drain hair remover.
2. Lift the trap out of the drain, rinse it under the tap and put it back properly, or you'll get a sewer smell.
3. Use a plunger with a few centimetres of water in the shower tray. On a bath, cover the overflow with a wet cloth so the pressure goes onto the blockage rather than escaping through the overflow.
4. Finish by running hot tap water down the drain. Don't use boiling water: PVC softens at high temperatures, and glued joints can start to leak.

Why we don't recommend chemical drain unblockers

A bottle of drain unblocker from the supermarket looks like a quick fix. The strong ones contain caustic soda or acid and get very hot inside the pipe, which can damage rubber seals and older metal pipes. If the product doesn't work, you're left with a corrosive liquid in the shower tray, and anyone who then uses a plunger or unscrews the trap risks splashes to the skin and eyes. Different products can also react violently with each other. A mild home remedy such as soda crystals and hot water, or baking soda and vinegar, will loosen a little soap scum at most; against a solid clump of hair it does very little.

When to stop and call us

Put the plunger down and call 085 333 4698 if:

• water is also coming up through another drain;
• two attempts with the grate and plunger get you nowhere;
• the trap can only be reached by removing a bath panel or tiles;
• dirty water is about to spill over the edge of the shower tray.

Unblocking a bathroom drain: how we work

When we unblock a shower drain, the engineer starts at the source, taking off the grate, trap or bath waste to see how far into the pipe the dirt goes. The drain itself can then usually be cleared from above, by hand or with a short hand-held drain snake.

If the blockage is further down, the next step is a thin drain snake or an electric drain machine with a spiral cable that can work its way round the bends of a narrow waste pipe. The rotating head breaks up the blockage and scrapes deposits off the pipe wall. Where a long horizontal pipe is coated in soap scum, we follow up with a narrow high-pressure hose. That leaves the pipe clean along its full length, rather than just punching a hole through the blockage.

If the problem is in the soil stack or the underground drain, we work through a rodding eye or the inspection chamber outside, not through the shower drain. That way the connection to your shower floor is left undisturbed. If the blockage keeps coming back in the same spot, a camera inspection of the pipe will show whether there's a sag, a badly fitted bend or hardened tile adhesive inside.

When we've finished, we run the shower and bath at full flow, even while the toilet is being flushed. We'll explain what caused the blockage and what you can do differently in future.

What shower drain unblocking costs

We charge from €129 to clear a blockage. That doesn't include the call-out charge, which we'll tell you separately before the engineer sets off. If you call in the evening, at night, at the weekend or on a public holiday, we charge the out-of-hours rate.

For bigger jobs, such as a recurring blockage in the soil stack of a block of flats, or cleaning every drain in a bathroom followed by a camera inspection, you can ask for a quote. Whatever the job, you'll always get a price estimate over the phone first, so you can decide before anyone heads your way.

Preventing repeat blockages

A few simple habits keep the shower and bath draining freely:

• Fit a hair catcher in the drain and empty it every few showers.
• Take the trap out once a month and rinse it clean.
• After a bath with bath oil or a body scrub, run some hot tap water down the drain.
• Never wash sand, paint water or leftover tile adhesive and grout down the shower.
• Run a rarely used shower, such as the one in a guest room, every so often so the trap stays full and no sewer smell gets into the house.

If the washbasin is slow to drain as well, the same mix of hair and soap is often sitting in its trap. Our page on washbasin unblocking explains how to tackle it.

Emergency: water in the bathroom after hours

A blocked shower is a nuisance, but it only becomes truly urgent when water spills over the edge of the shower tray or across the bathroom threshold. In a flat, it can be coming through your downstairs neighbours' ceiling before you know it. And if sewage is coming up out of the drain, you won't want to wait until Monday either.

Unblocking a shower drain in the evening, at night or at the weekend is routine work for us. We're available 24/7 on 085 333 4698, public holidays included, and the engineer is usually with you within the hour. In the meantime, use as little water as possible, switch off the washing machine and dishwasher, and lay towels along the threshold.

Our service area

Afvoer Ontstoppen works throughout the Netherlands, from Groningen to Nijmegen and from Haarlem to Zoetermeer. These and a number of other cities have their own page with local background, all listed in our overview of locations. For shower drain unblocking, the engineer brings the same equipment wherever you are, whether you live in a 1930s house or a new-build block of flats.

If several drains are blocked at once, see how our drain unblocking service checks an entire drainage system.