Pipe & Drain

Drain Cleaning Checklist: What to Try Before You Call a Plumber

November 14, 2025·5 min read

A slow drain is the most common plumbing complaint there is, and most of the time it is not a serious problem. Before you call anyone, it is worth five minutes of diagnosis — partly because some of these you can resolve yourself, and partly because the answers change what the right repair is.

Work through these five questions first

Is it one fixture or several? One slow sink is local to that fixture. Several at once, or the lowest drains in the building, points at the shared line rather than the trap.
Does it gurgle? Gurgling means air is being pulled past a partial blockage, or that a vent is restricted. Either way it usually sits further down the line than the fixture you are standing at.
Has it worsened gradually over weeks, or did it stop suddenly? Gradual points to buildup narrowing the pipe. Sudden points to an object, or to something shifting in the line.
Have chemical drain cleaners been used? Say so when you call. They can mask the symptom while attacking older pipe, and they make the line hazardous for whoever opens it.
Which room is it? Kitchen drains clog with grease and food solids. Bathroom drains clog with hair and soap scum. The cause differs, and so does the right method for clearing it.

What is worth trying yourself

For a single slow bathroom sink or tub, pull and clean the pop-up stopper or strainer first. A startling proportion of the slow drains we get called for are a stopper carrying a season's worth of hair, and clearing it takes two minutes with no tools.

A cup plunger works on sinks and tubs, but only if you block the overflow opening first — otherwise you are just moving air around. For a toilet, use a flange plunger, which is the one with the extra rubber sleeve.

Boiling water and dish soap can move a light grease clog in a kitchen sink. Skip that on a toilet or on anything with plastic traps, and never chase chemical drain cleaner with boiling water.

Why we keep telling people to skip the chemicals

Chemical drain cleaners work by generating heat and reacting with the blockage. In a modern PVC system with a light clog, that is usually survivable. In the older housing stock across most of this city, the pipe is often original galvanized steel or cast iron that has already lost wall thickness to decades of corrosion, and the chemical attacks that thinned metal as readily as the clog.

The second problem is that they rarely clear the blockage completely. They open a channel through it, the drain runs again for a week or two, and the remaining material catches the next thing that comes down. Meanwhile the standing chemical sits in the trap for whoever opens the line next.

If you have used one and are calling for service, just tell us. It is not a scolding — it genuinely changes how the technician opens the line.

Cabling versus hydro-jetting

Cabling, or snaking, drives a rotating cable through the line to break up or retrieve the blockage. It is the right tool for a solid obstruction, for hair, and for most single-fixture clogs, and it is what the majority of drain calls need.

Hydro-jetting uses high-pressure water to scour the full circumference of the pipe wall. On a grease-heavy kitchen line or a lateral with years of accumulated buildup, this is the meaningful difference: cabling punches a hole through the grease and restores flow, while jetting removes the grease. That is why a cabled grease line often backs up again within months and a jetted one does not.

Jetting is not right for every pipe. A line that is already structurally compromised — badly corroded cast iron, cracked clay — is not a good candidate, which is one of several reasons a camera inspection comes first when the history suggests the line itself is failing.

The signs that this is not a drain problem

More than one fixture slow or backing up at the same time
Water rising in a tub or shower when a toilet is flushed
Gurgling from a toilet when the washing machine drains
Sewage odor at a floor drain or in the cellar
A line that has needed clearing several times, with each clearing lasting less time than the last

Any of those move the conversation from drain cleaning to the main line, and the right next step is a camera inspection rather than another clearing.

Keeping drains clear afterward

The single most effective habit is not putting grease down a kitchen sink — not hot, not followed by hot water, not at all. Grease goes down warm and liquid and cools into a solid coating on the pipe wall a few feet along, and it is the reason multi-family kitchen lines clog as reliably as they do.

Beyond that: strainers in every sink and tub, no wipes down a toilet regardless of what the packaging claims, and run water through rarely-used fixtures every few weeks so the trap does not dry out and let sewer gas back into the room.

Frequently Asked Questions

We would rather you did not, especially in an older building. They can damage thinned galvanized and cast-iron pipe, they usually open a channel rather than clearing the blockage, and they leave standing chemical in the trap. If you already have, tell the technician — it changes how the line is opened.

Count the affected fixtures and check the lowest ones. A single slow sink with everything else draining normally is local. Multiple slow drains, a tub filling when a toilet flushes, or gurgling when the washing machine runs all point at the shared line.

Better for the right problem. Jetting scours the pipe wall and is the right answer for grease and heavy buildup. Cabling is better for solid obstructions and most single-fixture clogs. Jetting is also not appropriate for a pipe that is already structurally compromised.

Most single-family homes do not need scheduled drain cleaning at all — they need it when there is a symptom. Multi-family buildings with several kitchens on a shared line, and restaurants, are the exception and do benefit from a regular interval.

A partial clog occasionally passes. More often it collects material and gets worse, and the longer a kitchen line runs slow the more grease accumulates on the restriction. Waiting rarely improves the situation and sometimes turns a cleaning into a repair.

Not automatically — most single-fixture clogs do not need one. We recommend it when the history suggests the line itself is the problem: repeated backups, shrinking intervals between clearings, or multiple fixtures involved.