Blocked Drain Myths in Horsham | What's Actually True

I had a call last month from a homeowner in Roffey who'd poured half a bottle of bleach down his kitchen drain every week for a month. The sink was still backing up. He genuinely couldn't understand why.

He's not unusual. There are a handful of beliefs about blocked drains that have lodged themselves in people's minds, and they spread because they sound plausible. I hear them on jobs across RH12 and RH13 every single week. Let me go through the ones that cause the most damage.

Myth 1: Bleach Will Clear a Blocked Drain

This one's everywhere. The idea is that bleach is a powerful chemical, so it must dissolve whatever's in the pipe.

It doesn't work like that. Bleach is a disinfectant. It kills bacteria and whitens surfaces. It is not a degreaser, it does not dissolve fat, and it won't shift a compacted mass of wet wipes, hair and grease. What bleach will do is sit on top of the standing water in your blocked pipe, do essentially nothing to the blockage, and then slowly corrode older clay or iron pipework if you keep doing it.

I've pulled apart junctions in Broadbridge Heath and Littlehaven where homeowners have been dosing their drains with bleach for years. The blockage is still there. The pipe looks worse.

What actually works: high-pressure water jetting. It physically breaks up and flushes the obstruction. No chemical workaround comes close.

Myth 2: If It Says Flushable, It's Fine to Flush

I know there's already a post on this site about wipes specifically, so I won't labour it. But it's so embedded in the blocked-drain mythology that I can't leave it out.

"Flushable" on a packet is a marketing claim, not an engineering standard. The Water Industry's own testing is clear: most so-called flushable wipes do not break down at anything close to the rate toilet paper does. They catch on root ingress, they snag on the lips of old clay joints, and they bind together with cooking fat into a solid mass that a plunger simply cannot shift.

I've seen this in properties all over Horsham, from new-builds on the Trafalgar estate to Victorian terraces near the town centre. The pipe age doesn't matter. The wipes don't care.

Myth 3: A Plunger Always Gets It Moving

A plunger is useful for a soft, partial blockage close to the fixture. A sink that's draining slowly because of a soap and hair build-up just inside the trap, for instance. Fine. Give it a go.

But a plunger creates hydraulic pressure. It shifts things by force. If the blockage is further down the line, compacted solid, or held in place by something structural like a collapsed joint or a root mass, you're not shifting it with a plunger. You're just pushing pressure into a system that can't move.

I've been called to jobs in Southwater and Warnham where the homeowner had been plunging for days. Occasionally they'd managed to move the blockage further along the pipe, where it settled somewhere harder to reach. That's not a win.

If the plunger hasn't shifted it in two or three attempts, stop. You're not going to wear the blockage down by persistence.

Myth 4: Boiling Water Fixes a Greasy Drain

Part true. A kettle of boiling water poured slowly down a kitchen drain can melt a fresh, minor grease deposit near the top of the system. If you've just cooked a fatty meal and the drain is draining slowly, it's worth trying.

The problem is when people use this as their main strategy for months. Grease doesn't just sit neatly near the top. Over time it coats the full length of the pipe, cooled and hardened. Boiling water at the top does nothing to the grease 3 metres further along. And if your pipes are UPVC, repeatedly pouring boiling water into them can soften joints over time.

For anything beyond the mildest build-up, descaling and jetting is the right call.

What You Should Actually Do

If your drain is blocked:

• One go with a plunger, if the blockage seems close and soft. Two or three at most.
• Don't add chemicals. They won't help and may make the pipe harder to work on safely.
• If it's not shifting, call a drainage engineer, not a general plumber. Plumbers deal with pipe fittings. Drainage engineers have the jetting equipment and the CCTV kit to find out what's actually going on.

If your drain keeps blocking, that's the key word: keeps. A recurring blockage is not bad luck. Something is causing it, whether that's root ingress, a displaced joint, a collapsed section, or a chronic fat build-up. A CCTV drain survey will tell you exactly what and where. Guessing with bleach and boiling water for six months costs more in time and frustration than the survey does.

Drainsco covers Horsham and the surrounding RH postcodes, from Billingshurst and Pulborough up to Rudgwick and Slinfold. Engineers are on call around the clock, there's no call-out fee, and you'll get a clear price before we start any work.