Clear a sluggish drain with soda, vinegar and hot water
Skip the caustic drain cleaner: a scoop of bicarb, a splash of vinegar and a kettle of hot water shifts most everyday clogs safely, cheaply, and without harsh fumes pouring down your pipes.
Commercial drain unblockers are some of the harshest chemicals we casually keep under the sink — strong enough to burn skin and corrode pipes, sold to fix what’s usually just a build-up of hair, soap scum and grease. For everyday slow drains, you rarely need them. The humble combination of bicarbonate of soda and vinegar tackles the problem from two angles: the fizzing reaction physically agitates and loosens the gunk, and a follow-up flush of hot water melts and carries away the greasy film that’s narrowing your pipe.
It works best as maintenance and on early-stage clogs — the sink that’s draining a bit sluggishly, the shower that’s starting to pool. Catch it at that stage and a 30-minute fizz-and-flush will usually sort it, for a few cents instead of a fiver, with no fumes and nothing nasty heading to the treatment plant.
Be realistic about its limits, though. A completely blocked drain with water sitting on top is a mechanical problem that fizzing won’t solve — that’s when a plunger, a drain snake or a call to the plumber is the right move, and reaching for ever-stronger chemicals just risks your pipes and your lungs. The real long-term fix is prevention: a cheap hair-catcher over the plughole and the occasional hot-water rinse will keep most drains running freely and spare you the whole performance.
How to do it
- Clear standing water from the sink or basin and fish out any visible hair or gunk from the plughole first — a bent wire or a cheap plastic drain claw works well.
- Pour roughly half a cup of bicarbonate of soda (Natron / baking soda) straight down the drain, pushing it in if needed.
- Follow with about half a cup of plain white vinegar. It'll fizz energetically — that bubbling action helps loosen grease and grime on the pipe walls.
- Cover the plughole with a cloth or plug to keep the reaction working downwards, and leave it to do its thing for 15–30 minutes.
- Flush it through with a full kettle of just-off-the-boil water (use hot tap water, not boiling, if your pipes are plastic or you have a ceramic basin) to wash the loosened debris away.
- Still slow? Repeat once, or try a sink plunger or drain snake before you reach for anything stronger.
Pro tips & pitfalls
- Never mix this with a shop-bought chemical drain cleaner — if one's already in the pipe, the combination can release dangerous fumes. Choose one approach, not both.
- Prevention beats cure: a €2 drain hair-catcher over the plughole stops most clogs forming in the first place, and a weekly hot-water flush keeps grease moving.
- For a fully blocked, standing-water drain this gentle method often isn't enough — that's a job for a plunger, a drain snake, or a plumber, not stronger chemicals.
What it's good for
Good for the planet
- Fewer toxins Avoids caustic soda and bleach-based drain cleaners that burn skin, give off fumes, and send harsh chemicals straight into the water system.
- Cuts waste Two pantry staples in cardboard or refillable packaging replace single-use plastic bottles of one-job chemical cleaner.
- Protects nature Keeps corrosive cleaners out of wastewater and waterways, where they're tough on treatment systems and aquatic life.
Good for you
- Saves money Bicarb and vinegar cost a few cents per use versus €5–10 a bottle for branded drain unblockers — and a hair-catcher saves the lot.
Find your next hack
Browse more home hacks, or jump to another part of your life.
More home hacks All categories