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What is a Soil Stack?

What is a Soil Stack?


Every building that has drainage pipe systems: toilets, sinks, and baths, are connected to a series of interconnected pipes. Together, they all connect to a network of horizontal pipes called waste pipes, or soil and vent pipes. These horizontal pipes transport any wastewater from a property by joining with a vertical pipe outside of the building.

It is the vertical pipe located outside the building that is known as the soil stack – characterised by an occasional sound from the flow of water as wastewater flows downwards from an upper drain. 

Once any wastewater from a property hits the vertical soil stack, any solid waste and wastewater travel down the pipe and gases travel up through the soil stack vent and air admittance valve which prevents smells. At the bottom of the soil stack, an exit to a waste-removal system can be found. This exit could lead to a sewer is located in an urban area, or to a septic tank if the building is in a rural area. 

If any gases are not allowed to vent through the top of the pipework’s air admittance valve because it has somehow become blocked, the gases will eventually vent through the easiest opening in the building due to the increase of pressure in the pipe. This will alleviate the pressure within the pipe, however, the building will be filled with harmful and foul-smelling gases. 

blocked soil stack

How do Waste and Soil Pipes Become Blocked? 

There are numerous ways that waste and soil stack pipes can find themselves becoming blocked, and when this does happen; you may need to hire a professional to carry out a soil stack repair service. In the event your soil stack does become blocked or requires a professional to service the pipe, Coastal Drains is always here to help in this situation.

Horizontal waste pipes frequently become blocked and blocked due to non-flushable items being flushed down the toilet, as well as fats, oils, and grease being washed down sinks in kitchens. The vertical soil stack pipe can also be affected by these blockages, as well as the build-up of uratic salt. Uratic salt can narrow the soil stack pipe, blocking waste from flowing through the pipe. There are a few common signs that signify a problem within your soil stack pipe system. These can include:

  • Toilets draining away far more slowly than usual
  • Toilets becoming blocked when flushing
  • Sinks, showers, and baths not draining water efficiently
  • Foul-smelling gases coming from drains within the property

It often rings true that blockages are worse at the bottom of the soil stack. This is because the bottom of the stack is where refuse, waste, and non-flushable items can collect, which causes the crux of the problem. If you have a blockage at the bottom of the soil stack, there are further signs that can alert you to this. This includes:

  • Water bursting or leaking from the joints of the soil stack pipe
  • Overflowing dirty water and wastewater at the bottom of the pipe

If you notice any of these telltale signs as listed above, this is a sign for you to act fast before the problem becomes even worse and causes an even more costly problem in the future. Don’t wait around before it is too late, get in touch with the friendly experts at Coastal Drains. 

How Can You Prevent Soil Stack Blockages?

Blocked waste pipes and soil stacks can pose a significant problem to any property. For commercial properties and businesses, daily duties can grind to a halt whilst the problem is dealt with, and for homes, the health of the entire household can be put at risk. A simple blockage can create significantly worse problems later down the line if it is not dealt with in its initial stages. 

In order to remove this threat, a routine maintenance plan for soil stack cleaning can prevent the need for emergency callouts or any costly reactive services. This is because the problem will be identified before it arises, and solved there and then – keeping the build-up of uratic salt and any debris at bay. 

If you would like to set up a regular soil stack service with our experts at Coastal Drains, please do get in touch, as the problems that occur when a soil stack is left unattended can be extremely costly. We offer free on-site assessments, no-obligation quotes, as well as routine maintenance from the first point of contact. 

At Coastal Drains, our expert drainage engineers can advise, and provide, the most effective services for the soil stack on your property. These include: 

  • High-pressure water jetting with state of the art equipment
  • CCTV drain surveys
  • Drain repairs

Soil Stack and Soil Pipe Repairs

In the event your soil stack and waste pipes have suffered any structural damage due to tree root growth, flooding, or other natural causes, Coastal Drains are always on hand to provide the best possible resolutions. We can arrive on your property to assess and repair the problem in a swift and efficient manner. We always aim to provide non-invasive solutions to problems, only digging where absolutely necessary. 

When it comes to soil stack repairs, we aim to use no-dig drain repairs and pipe lining services, where a new pipe is essentially wrapped over the inside of the existing pipe, sealing any structural damage and providing a sturdy solution. This eliminates the need to dig and ruin any landscaping on your property, as well as removing the need for a complete replacement of the soil stack unit. 

Contact Coastal Drains Today For Soil Stack Services

Does your soil stack have a blockage that needs to be dealt with? Does your soil stack pipe have a structural weakness that is compromising the integrity of your entire soil stack system? If so, waiting for the problem to resolve itself won’t work – it’ll only create a problem that is even more costly to fix. 

For a no-obligation quotation, get in touch with Coastal Drains today.