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Buying a house with a septic tank

The Septic Tank Sizing Scam

A guide to help avoid one of the common survey scams. To arrange a home buyers survey for your new property please call us on 0800 3101092 or via our contact form.

The Septic Tank Size scam

The implementation of the General Binding Rules has bought a lot of change. This has attracted a lot of new companies and traditional mains drainage companies to start operating in this area. Many are now offering Septic Tank Surveys. It has been seen recently, especially with home buyers surveys, a lot of incorrect assessments being made. Some stipulate that old systems need to be replaced at the cost of £10’s of thousands of pounds. Some of this advice may be misplaced but certainly, some of it is intentional. 

Tips for avoiding issues with a survey:

  • Avoid free surveys or assesments. If a company is coming out for “free” to assess your tank for compliance then you should expect issues to be found.
  • Avoid drainage companies that do not specialise in off mains drainage.
  • Look for a reputable LTD company.
  • Please check our homebuyers survey page to get other hints and tips.

The too Small Scam

The latest scam being seeing in the industry is companies telling Septic Tank owners that their tanks are too small.  Then, as a result, a new tank needs to be installed. If this has been presented to you as fait accompli then please read the following advice. In all cases, the first step should be to make an EA permit application. If you believe your tank to be too small and you are worried about this.

The Rules

The `Building Regulations 2010’ document part H dictates that septic tanks for domestic dwellings should be designed for the maximum potential number of occupants. The method of calculating whether a septic tank is correctly sized is as follows:

The first two bedrooms of a property can have a maximum of 2 people each. One person should then be added for every bedroom thereafter, (number of bedrooms + 2 = maximum occupancy). Septic tanks are usually sized in litres with the minimum size allowed being 2,700 litre capacity below the inlet pipe of the tank for the first two bedrooms (4 people), then an additional 180 litres should be added for every bedroom (1 person) after this.

An Example

 For example, A 5-bedroom property per British Water flows and Loads should have a system designed to deal with an occupancy of 7 people which works out at 2,700 litres for the first 4 people (2 bedrooms) plus 3 additional people (2 additional bedrooms) at 180 litres each person = 2,700 + 3 x 180 litres = A minimum capacity of 3,240 litres below the inlet pipe of the tank.

When a tank is undersized for a property, the settlement and separation processes within the tank won’t have time to function efficiently. If a tank is slightly undersized for a property and is used at the maximum occupancy for a prolonged period, then the solid waste will build up in the tank faster than usual. This means that the quality of the effluent leaving the tank can be compromised, and there will potentially be a requirement to empty the system more frequently.

What does this mean?

The ‘General Binding Rules for small sewage discharges to ground’ state that your treatment system must be large enough to handle the maximum amount of sewage it will need to treat. If the amount of sewage the system needs to treat increases (for example, because you’ve extended your property or connected an additional property), you must make recalculate to sure the treatment system is still big enough.

In either case, if a system is thought to be undersized a permit application would be recommended. If the tank is only slightly undersized, in our experience this would not usually affect the performance of the system. Unless it is used at the maximum occupancy for an extended period and an EA permit will likely be issued if the system is in good working order. If the capacity required has increased due to expansion to a property since 2015 then a permit is less likely to be issued.

Want to learn more?

We have a large collection of articles containing the answer to all of your questions. Check out our Blog Page 

Our Core Services: The Sewage Treatment expert Installers

On the 1st January 2020, all Septic Tanks that discharge to a Stream, Watercourse or Drainage Ditch will become illegal and will require replacing with a Sewage Treatment Plant. Please see here for more details.

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Expert wastewater treatment engineers who specialise in Septic Tank and Soakaway replacements as well as Sewage Treatment Installations. We are based in the New Forest, Hampshire but operate across the South Coast as well as Wiltshire, Somerset, Devon, Sussex, Surrey, Oxfordshire, and Berkshire.

The Home of Septic tank and private drainage system solutions. 

Based in the New Forest, Hampshire on the border with Dorset and Wiltshire we operate an expert team of off-mains drainage specialists. This encompasses Septic Tank, Soakaway and drainage system problems, installations, blockages, and servicing. In addition, any issues relating to cesspits and sewage treatment plants.

Homeseptic offers high quality, professional advice, repairs and installation for all aspects of effluent cleansing and disposal across the south of England. Whether you’re looking for septic tank installation, sewerage treatment plants or systems, piping or soakaway solutions, Homeseptic employs only the most competent engineers in the drainage and treatment industry and knows exactly which solutions suit each property.

We only install and offer quality systems we believe in, from suppliers we know and trust.

New Forest Philosophy

As we have said Homeseptic is based in the New Forest. A great location in between the cities of Southampton, Salisbury and Bournemouth. We are a group of good friends who grew up together in the area.  Individually we all have grown tired of the way other Drainage firms are run. As a result, this is why we set up Homeseptic. If you want to know more please check out our About Page

We want to actually put the customer first and turn up to do a great job that we can be proud of. Unfortunately, this is not the case in the market, with most companies pressuring their workers to sell unnecessary works on a visit. Due to this, we offer upfront quotations with any variations discussed before we start work.

We are honest hard working professionals, which we hope you will agree with. As a result, it will certainly not turn up in flash sales vehicles and give you a load of chat and then do a terrible job. Our team will come with the job in mind and the aim of giving you the best value we can in order to facilitate a quality installation. 

We cover all of Hampshire, West Sussex, Dorset, Somerset, and Wiltshire. Please get in touch and see what you think.

The Septic Tank sizing Scam
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The Septic Tank sizing Scam
A guide for new homeowners who are looking to sell their property.
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