For homes in more rural areas of the country, it is not uncommon for these properties to be using off-mains drainage systems, such as septic tanks, sewage treatment plants or cesspits. If you share your septic tank with your neighbour (or neighbours) it can often be a more cost-saving and effective solution, as opposed to an individual system. However, if you have a shared septic tank or are buying a property with a shared system, there are a few important things you need to know.

Keeping a Compliant Shared Septic System

For most homes in the UK, shared septic systems are shared between a couple of homes, usually semi-detached or terraced houses.

Usually, when a home is on a shared system, the maintenance works needed to ensure the smooth running of the septic tank, sewage treatment plant or cesspit will be noted in the deeds of the property. Each homeowner will have a responsibility to carry out regular works on the septic system, such as regular surveys, septic tank emptying or resolving issues that arise. They will also need to ensure that the waste they are putting into the septic tank is appropriate, meaning they will not cause any additional damage or blockages which would impact the other homes on the system. If you are unsure what can go into your septic tank, click here to read our guide. 

Sometimes, these agreements can be more informal and are a spoken agreement between neighbours. Although this works for some, it is much better to have a formal written agreement in place to avoid any misunderstandings later down the line.

Resolving Drainage Issues of a Shared Septic Tank

Just like with individual tanks, a shared septic tank can often run into a number of issues. Cracked pipes, blockages, overfilling and rodent infestations can all cause huge issues with your septic system. When it comes to resolving these, it is often the case that the responsibility is shared equally between the neighbours. 

This is the same for the costs. Most often, the cost of repairing a shared septic tank is shared equally between the homes; however you must check your deeds or signed paperwork to make sure this is the case. 

If you have run into problems with your shared septic tank, book your visit from our drainage experts below.

Common Septic Tank Problems


Shared Septic Tank FAQ’s

What do I need to do if I am buying a home with a shared septic tank?

If your new home does use a shared septic tank, a homebuyers drainage survey is recommended before any final sign off occurs. These surveys look into the health of the properties drainage system, including the shared septic tank. A CCTV camera feeds a live video to the technician carrying out the inspection, who will then offer a report of their findings. This is extremely important for a number of reasons. Firstly, a homebuyers drainage survey can be used when securing home insurance whilst also offering you peace of mind that the home you will be purchasing will not be subject to any messy situations in the near future. It is also recommended to read and understand the deeds of the tank.

How many homes can a shared septic tank support?

Septic tanks, sewage treatment plants and cesspits come in all shapes and sizes. The more homes which need to share the tank will naturally require a larger tank to ensure over filling does not occur. When you are buying a septic tank for the first time, or having once replaced, it is important to know how many people will be using it, so an accurate water output can be calculated.

Can I access a shared septic tank which is not on my property?

If your shared septic system is situated on a neighbour’s property, your deeds should outline what access you have to the tank. Although the tank is not on your land, you do still have the responsibility to look after the tank, which may require access.

Who pays for a shared septic tank?

As we have covered, the cost of maintenance, repairs, emergency call outs or replacements should be split equally between all homes, as should be detailed in your deeds.


Benefits of Proseptic

No obligation sewage treatment plant advice

  • If you are have any questions about installing a sewage treatment plant or are unsure if your existing septic system meets the latest regulations, please get in touch. Our friendly, expert team are always happy to share our drainage expertise to help you make the right decisions.

Fitted by expert engineers

  • Our engineers have extensive experience in the sewage treatment industry. Therefore, you know that all sewage treatment surveys, inspections, installations and on-going maintenance will be conducted professionally. We pride ourselves on our customer service which is why most of our work actually comes from client referrals.

What you can expect from Proseptic

  • Our customers are more than a sales opportunity. We want your sewage treatment plant to work for you. Therefore, we deliver all sewage treatment plant installations with quality, efficiency and minimal hassle.
  • We endeavour to explain all sewage treatment options to you so that you can feel confident and make an informed decision, armed with all the information available.