Fat, Oil and Grease (FOG): The Silent Drain Killer

When it comes to blocked drains, one of the biggest culprits is something many of us pour down the sink every day without giving it a second thought – fat, oil and grease (FOG).

Whether it's leftover cooking oil, melted butter, meat fat, or greasy food residue washed from plates, these substances can cause serious damage to your drainage system over time. While they may go down the drain as liquids, they quickly cool, solidify, and begin to stick to the inside of your pipework, gradually restricting the flow of wastewater.

Drain Full of Solid Grease

What Is FOG?

FOG stands for Fat, Oil and Grease and includes common kitchen waste such as:

• Cooking oils

• Fat from meat and bacon

• Butter and margarine

• Gravy and sauces

• Dairy products

• Food scraps coated in grease

Although these materials may seem harmless, they are one of the leading causes of blocked drains in both domestic and commercial properties.

Why Is FOG So Harmful?

As fat, oil and grease travel through your drainage system, they begin to cool and harden. Over time, they build up along the walls of the pipes, reducing the available space for wastewater to flow.

Eventually, this build-up can lead to:

• Slow-draining sinks

• Unpleasant odours

• Recurring drain blockages

• Overflowing gullies

• Backed-up sinks and appliances

• Expensive drainage repairs

In severe cases, FOG combines with other debris, such as wet wipes and food waste, to form large solid masses often referred to as "fatbergs." These can completely block drainage systems and require specialist equipment to remove.

Grease Build Up in Drain

Commercial Properties Are Especially at Risk

Restaurants, cafés, hotels, pubs, schools, and food production facilities produce significantly more grease than the average household. Without proper maintenance, grease can quickly accumulate in drainage systems, leading to frequent blockages and costly disruption to business operations.

Regular grease trap maintenance and routine high-pressure water jetting are essential to keep commercial drainage systems operating efficiently and to prevent unexpected emergencies.

How Can You Prevent FOG Build-Up?

Preventing grease-related blockages is much easier than dealing with the damage they cause. Some simple steps include:

• Never pour cooking oil or fat down the sink.

• Allow grease to cool before disposing of it in the bin.

• Scrape food waste into the rubbish before washing dishes.

• Use sink strainers to catch food particles.

• Schedule regular grease trap maintenance if you operate a commercial kitchen.

These small habits can significantly reduce the risk of blocked drains and extend the lifespan of your drainage system.

Professional Drain Cleaning

If your drains are already showing signs of a blockage, it is important to act quickly. Professional high-pressure water jetting is one of the most effective ways to remove grease build-up and restore your drains to full working order.

For recurring blockages, a CCTV drainage survey may also be recommended to ensure there are no underlying structural issues contributing to the problem.

Need Help with a Blocked Drain?

If you're experiencing slow-draining sinks, unpleasant smells, or recurring blockages, don't ignore the warning signs. Fat, oil and grease build-up can become a serious problem if left untreated.

Contact Drain Doctor today on 1800 946 366 to arrange a professional drain inspection or high-pressure water jetting service. Our experienced team is available 24 hours a day, 365 days a year, helping homeowners and businesses keep their drainage systems flowing freely.