Plumbers and cleaning experts say the popular baking soda and vinegar method rarely clears a blocked kitchen sink, and they recommend soda crystals as a natural alternative that works in about five minutes.
Clear Stream Drainage and cleaning expert Wendy Graham, who runs the eco-blog Moral Fibres, said the fizzing reaction between baking soda and vinegar creates water with a small amount of salt in it, and unblocking a drain with salty water is "rarely effective". Graham added, "You need something that will break down the fat and tackle the oil and grease that is lodged in your drain."
Why the fizzing reaction fails
Plumbing experts at Clear Stream said "baking soda and vinegar cannot unblock a drain in any meaningful way". They added, "The reaction shifts light, loose residue and can freshen a mild odour, but it has no power over the fat and scale that cause almost every real blockage. It is a light maintenance rinse, not a drain unblocker."
The fizz cannot shift a real blockage because drains are "an open system", the plumber explained. Any pressure generated by the reaction escapes straight back up the plughole and out through the vent pipe, meaning virtually no force reaches the blockage. The reaction is also short-lived and takes place in the sink rather than deep within the pipe where blockages develop. The experts added, "The visible foam stays up near the plughole. The blockage sits a metre or more further down. The two rarely meet."
Using soda crystals instead
For a more reliable alternative, Graham recommends "using soda crystals to help unblock drains naturally". Soda crystals have detergent properties, which help tackle dirt and grease, making them effective at dealing with fat-clogged drains in the kitchen.
To start, boil a full kettle of water and pour it carefully and slowly down the drain. This helps break down any fat blockages. Once the boiling water has fully drained away, tip a large cup of soda crystals down the plughole and allow it to sit for five to 10 minutes to break down fat and grease deposits. Then boil another full kettle of water and pour it down the drain to flush away the soda crystals along with the loosened fat and grease, being cautious of splashes of boiling water as the soda crystals tackle the blockage.
Repeat the first and last steps until the drain runs clear, with an improvement expected each time the process is repeated.
