Common Causes For Blocked Drains

Common Causes For Blocked Drains

Most homes and businesses at some point will experience a drain blockage. Often, the blockage will be cleared but the underlying cause not dealt with. This will only lead to further blockages in the future if not investigated fully. With this in mind, here are the seven most likely causes for drain blockages:


When leaves get wet, they will clump together and can block drain water from flowing freely. This is especially common in the autumn when the volume of leaves on the ground is at its highest. Tree roots can also cause drainage problems as they can often split drain casing in their search for water.

Cooking oils/grease

Grease and fat cling to pipes when poured down the sink and are a major cause of drain blockages. Grease is often poured down the kitchen sink straight from pans or trays when it is still warm and liquefied. However, as the grease and fat cools, it solidifies and coats the inside of the drainpipes. Over time this layer of grease will thicken, restricting the flow of wastewater and cause a blockage.


Hair is often rinsed away down the plughole, often unknowingly, after a bath or shower. Seemingly small and innocuous, hair can cause a big problem in drains. Hair will stick together and collect into a large mass. This can cause problems with water flowing freely and, if left untreated, can block a drain altogether. This problem can be avoided if you use products designed to prevent the hair going down the plughole.

Bathroom Consumables

Foreign objects that are not designed to end up in drains are often a cause of blockages. Wet wipes or face wipes are a common culprit for blocking drains, as they don’t disintegrate like toilet paper is designed to do. However if an overly large amount of toilet paper is flushed, it can cause a blocked drain too. Other common objects guilty of causing blockages are sanitary towels, hair clips and cotton wool.

Adverse weather

Storms and heavy rainfall can cause blocked drains if they are not built to hold high levels of water. During a storm, pipes are often subject to higher water pressure as more and more rainwater enters them, which can lead to a burst pipe. Storms also wash extra debris, such as mud and leaves, into drains, also leading to blockages.

DIY problems

In an age where DIY is highly popular, many people attempt tasks that they don’t have the skills to complete. Bad workmanship can lead to pipes being installed incorrectly or the wrong pipes being used, this then results blockages as the water attempts to flow through badly aligned pipes or pipes that are too small.

Wear and tear

Drainpipes do not last forever and a broken or split pipe will result in water backing up and causing a blockage. A broken pipe should be replaced as soon as possible to prevent further blockages or possible flooding.

Once a professional diagnoses the root cause of the blockage, they should be able to offer you a solution to avoid the same problem in future. Drainage Consultants are UK drainage specialists leading the way in CCTV drain surveys and drains repairs.