Open Hours

24 hours a day

What is a Soil Stack, and How to Unblock it?




July 11, 2023



Soil Stack

Table of Contents

Sanitary pipes hold a key significance in making a building functional and habitable. Joined through specific interconnections, these pipes, on the one hand, ensure a continuous supply of water. On the other hand, they drive wastewater from bathrooms, kitchens, etc., to the main sewerage supply.

A critical component of these complicated sanitary pipes is soil stack. A soil stack, also known as a soil pipe or waste stack, is an essential pipe of a building’s plumbing system outside the building.

It is a vertical pipe that carries waste and wastewater from toilets, sinks, and other plumbing fixtures to the sewer or septic system. It connects to horizontal branch pipes on various building floors, allowing for the proper disposal of waste without causing blockages or backups.

Why Is A Soil Stack Significant?

The soil stack is significant in many aspects of a building’s plumbing system. First, it efficiently disposes of waste by transporting it from toilets, sinks, and other fixtures to the sewer or septic system.

Moreover, the soil stack provides ventilation by incorporating vent pipes that release odours, gases, and pressure build-up from the drainage system. This ventilation maintains proper air pressure, prevents traps from being siphoned, and ensures uninterrupted waste flow.

Besides this, the soil stack offers structural support to the plumbing system, distributing the weight of waste and preventing misalignment or damage. Lastly, building regulations ensure that the soil stack meets safety and sanitation standards which means the plumbing infrastructure is reliable.

What is a Soil Stack, and How to Unblock it

Key Issues with the Soil Stack

Several issues are associated with the soil stack regarding its functionality, maintenance, and fitting. Let’s look at some of these:

  • Blockages: Soil stacks can experience blockages due to the build-up of solid waste, debris, or foreign objects. Blockages can lead to backups, slow drainage, or even complete obstructions, causing inconvenience and potential damage to the plumbing system.
  • Ventilation Problems: Inadequate ventilation or blockage of the vent pipes connected to the soil stack can cause problems. Insufficient ventilation can lead to foul odours and decreased drainage efficiency.
  • Leaks: Leaks in the soil stack can occur for various reasons, such as corrosion, deteriorated seals or joints, or physical damage. Such water leaks can cause lead to mould growth causing severe damage to the building structure and its integrity.
  • Misalignment or Damage: Soil stacks can experience misalignment or damage due to building settling, poor installation, or external forces.
  • Lack of Maintenance: Neglecting regular maintenance of the soil stack can contribute to various issues. Lack of cleaning, inspection, and maintenance can lead to blockages, reduced efficiency, and increased vulnerability to leaks or other problems.

Blockage is a very common issue among these problems that every person faces now and then. Let’s discover the reasons for pipe blockage and how you can deal with those problems.

Why Does a Soil Stack Get Blocked?

Several reasons for blocking a soil stack are associated with its maintenance or obstruction due to foreign objects. Below are some of the key reasons for a soil stack:

  • Accumulation of Solid Waste: One of the primary reasons for blockages is the build-up of solid waste materials within the soil stack. This can happen if items like sanitary products, wet wipes, or excessive amounts of toilet paper are flushed down the toilet. These materials can accumulate and create blockages within the pipe, impeding the flow of the pipe.
  • Grease and Fat Deposits: Pouring grease or fat down kitchen sinks can lead to blockages in the soil stack. Over time, grease and fat can solidify and stick to the pipe’s inner walls, ultimately narrowing the pipe’s diameter.
  • Accumulation of Mineral Deposits: Persistent presence of hard water leads to mineral deposition inside the soil stack. With time, these deposits harden to block the pipe’s diameter, restricting the continuous flow of waste.
What is a Soil Stack, and How to Unblock it

How to Unblock Your Soil Stack?

By following the below useful tips, you can resolve the blockage issue of the soil stack.

  • Firstly, attire properly with protective clothing and a face mask to protect yourself from waste or trash in the pipe
  • Now carefully spot the ‘cleaning eye’; the large hinge where all the adjacent pipes join the main stack.
  • Once you locate it, unscrew it and pass the auger through it.
  • Crank the handle of the auger that will release a coiled wire.
  • Now push and pull the auger that will break apart the blocking mass of the waste.
  • When water starts flowing easily through the pipe, disinfect the pipe using an anti-bacterial spray and place the pipe components back.

The soil stack is the main pipe joined with the complicated network of all the waste pipes of the building. Unblocking it demands a careful approach. Therefore, it is better recommended to approach professionals for a reliable service.

Tips to Avoid Blockage Problems

To clear blockage issues, you can take preventive measures to ensure a continuous waste flow from the soil stack.

  • Clearing Blockages: It is pertinent to clear the obstruction to restore the proper flow of waste material using chemical drain cleaners. Remember that these chemical drainers are harsh, so be careful.
  • Proper Waste Disposal: It is another key tip to prevent future blockages. Items like sanitary products, wet wipes, or excessive toilet paper should not be flushed down the pipe. Additionally, kitchen sinks should not be used for disposing of grease or fat. Instead, collect and dispose of them in the appropriate waste containers.
  • Regular Maintenance: Implement a regular maintenance schedule for the soil stack. This can include periodic inspections, cleaning, and preventive measures such as using effective drain cleaners to prevent the build-up of grease, fat, or scale. Apart from this, hire professional plumbers who will maintain your soil stack and guide you to keep it functioning.
  • Avoiding Foreign Object Disposal: Encourage your employees to effectively use waste disposal systems and avoid flushing foreign objects (that cause potential blockages) down toilets or sinks. Also, install trash bins at appropriate points in the building to reduce careless dumping of waste items.

Briefly, soil stack is the key pipe that carries away all the waste from your residential or commercial property; therefore, keeping it clear for an easy flow of waste is paramount. If it gets blocked, it is recommended to hire the services of the professional staff of Fast Drains. They are skilled, well-trained, and well-equipped to quickly clear your pipe. Therefore, next time you’re facing a blockage issue with your pipe, get in touch with us and have peace of mind by getting our insured services at reasonable costs.