Septic Tank Installations
If your residential home or commercial premises is not attached to the main sewer line, you are very likely to have a septic tank system attached to your home or building. Septic tanks handle wastewater collection, treatment and disposal in place of it running off to the sewer line. Septic tank systems require being installed underground to hold wastewater and a soil absorption system to disperse clean wastewater back to the land. Often, it can be difficult to predict the cost of a septic tank installation and there is a very good reason for that. There are many different factors that can affect the actual cost of having a septic tank installed – including tank size and material, permitting requirements, soil makeup and installation charges, which can all affect the cost of a septic system.
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We only serve customers within a 40 mile radius of our Halifax base – please see the map for more information. We may be able to help on larger jobs further afield, however we do not offer a nationwide service.
On This Page:
- How do septic tanks work?
- Installing a septic tank
- Septic tank prices
- Cost of a septic system for a 3-bedroom house
- Septic tank emptying costs
- Septic tank replacement costs
How Do Septic Tanks Work?
Septic tanks use a combination of nature and proven technological methods to treat household plumbing wastewater from bathrooms, laundry and kitchen drain. Typically, a septic tank system will consist of a septic tank, a drain field or soil absorption field. The tanks digest organic matter and separate out floatable materials, like oils and grease, from solids in the wastewater. Soil-based systems are used for the discharge of liquid, effluent, which channels clean wastewater from the septic tank into perforated pipes. The pipes are buried in specialised units like leaching chambers that are designed to slowly release the effluent into the surrounding soil or surface water.
There are also alternative systems that utilise pumps or gravity to help the clean wastewater to trickle through less coarse materials like sand, organic matter (peat, sawdust etc.) or constructed wetlands to remove or neutralise pollutants like disease-causing pathogens and minerals like nitrogen or phosphorus that can contaminate the area. These systems can also be used in conjunction with ones that are designed to evaporate wastewater or even disinfect it before it is released into the surrounding soil or surface waters.
Installing A Septic Tank
The very first step in a septic tank installation is performing a survey on the site, including a soil test on the area where the system is going to be installed. Following the results of the survey, the septic tank system can be designed, pending the appropriate permits and approvals that need to be applied for.
Once the necessary permits are approved, the ground can be broken on your septic tank installation. A hole at least 2 feet deep must be excavated for your septic tank to sit in. It should be planned for the wastewater to flow downhill from here if you are installing a gravity fed system. This is because there are no mechanical means to expel the water as gravity is used to discharge it to the drain field.
4” Sch. 40 should be piped a foot through the trench wall or the floor, if you’re choosing that method of wastewater dispersion, to a minimum of five feet outside the building toward the tank. Make sure it is set to level through the wall or ground and run about 1/8” per foot of slope toward where the septic tank will lay.
A hole should then be excavated and be large enough to set the large concrete aerobic tank below ground. Layout and determine your leach field which has been determined in the survey and approved by the planning officer. During the process, remember to maintain a positive flow between the tank itself and the appropriate drain field. Finally, cover up the pipes and tank once you have a green tag from the health inspector.
Alternatively, if a pump chamber system is being installed, a small chamber next to the where the septic tank will lay should be excavated. The pump chamber should be installed after the septic tank, it will be used to move effluent from place to place and into the drain field for its final disposal.
Septic Tank Prices
Contacting a reputable septic tank installation professional for a consultation and quote is the first step you should take when looking at installing a septic tank. The cost of installing a septic tank will depend on the size required and the labour costs of the company that is installing it.
Typical cost for a Septic Tank for One House:
- Tank Cost: From £790 (depending on tank size)
- Installation Cost: From £1,500 (depending on tank size)
- Soakaway System: From £5,200 (starting at 100m of drains)
- Total Cost: From £7,490
If it is found that a septic tank and land drainage system is unsuitable to treat the sewage from your home, then there are several sewage treatment systems available that can remove substantial amounts of pollution that are contained in the wastewater and help protect the environment.
Traditional Sewage Treatment Plant for a Single Home:
- Plant Cost: Between £1,800 and £3,200
- Installation Cost: Between £2,000 and £3,000+ (depending on which model you require)
- Land Drainage System Cost: £5,200 (for 100m of drains)
- Total Cost: £4,000 to £11,400+
Modern Extended Aeration Sewage Treatment Plant for a Single Home:
- Plant Cost: Between £1850 and £2400
- Installation Cost: Between £600 and £3,000
- Drainage System: £25 per metre of drain run
- Total Cost: Between £2,260 and £5,400
Filter Sewage Treatment Plant for a Single Home:
- Plant Cost: £2,500
- Installation Cost: Between £2,000 and £4,000
- Drainage System: £20 per metre of drain run
- Total Cost: Between £4,500 and £7,500
Reed Bed Sewage Treatment for a Single Home:
- Septic Tank Installed Price: £2250
- Total Supply and Installation Cost: £8,500
- Land Drainage System: £5,200 (for 100m of drains)
- Total Cost: £15,950
Cost of a Septic Tank System for a 3-Bedroom House
A Cesspool or Cesspit is the most commonly required for a family home with 3-bedrooms or more. They are among the biggest and most expensive tanks to install and are very expensive to run. This is because emptying them requires removing each litre from the sealed tank.
Typical Costs for a Single 3-Bedroom House:
- Tank Cost: £3,500
- Installation Cost: £6,500
- Total Cost: £10,000
Septic Tank System for a 3-Bedroom House Typical Maintenance Costs:
- Average Family of 4 Peoples x 200 Litres Per Day: 800 litres per day volume discharged
- Minimum tank capacity: 18,000 litres storage capacity: 18,000 / 800 = 22.5 days
- Therefore, a tank will require emptying 365 / 22.5 = 16.2 times per year
- Average Emptying Cost is Around £180 per 4,500 litres, a complete emptying of 18,000 litres would cost £720, 16 times per year
- Average Annual Cost: £11,520
Septic Tank Emptying Costs
One of the biggest cost for septic tanks is the emptying of the vast amounts of liquid but if you go with the right tank you can balance the costs much more. Below is a list of the typical costs for emptying tanks which breaks down the costs into emptying and other maintenance that needs to be done to septic tanks and sewage treatment.
Reed Bed Sewage Treatment for a Single Home Typical Maintenance Costs:
- Tank Emptying: £180 per year
- Power Consumption: £290 per year
- Maintenance: £450
- Total reedbed replacement required every 10 years
- Average Annual Cost: £2,515 per year
Filter Sewage Treatment Plant for a Single Home Typical Maintenance Costs:
- Tank Emptying: £100 per year
- Power Consumption: £0
- Maintenance Service: £100
- Replacement Filter Bags: £50
- Average Annual Cost: £250 per year
Modern Extended Aeration Sewage Treatment Plant for a Single Home Typical Maintenance Costs:
- Tank Emptying: £100 per year
- Power Consumption: Between £25 and £180 per year (depending on which model you require)
- Maintenance Service: Between £100 and £130 (depending on which model you require)
- Average Annual Cost: Between £225 and £410 per year
Septic Tank for One House Typical Maintenance Costs:
- Emptying once per year: £150 per year
- Percentage cost of replacement soakaway (every 10 years average): £520
- Average annual cost: £670
Sewage Treatment Plant for a Single Home Typical Maintenance Costs:
- Tank Emptying: Between £100 and £400 (depending on frequency)
- Power Consumption: Between £80 and £180 (depending on which model you require)
- Maintenance Service: Between £100 and £375 per year (depending on which model you require)
- Average Annual Cost: Between £285 and £955 per year
Septic Tank Replacement Costs
If you notice unpleasant smells in your garden, it may be down to your septic tank being damaged. Often, people will think that the tank simply needs emptying but if you get a company out to empty your septic tank you will soon find out that the whole thing needs to be replaced. Unfortunately, this means that damaged septic tanks can cause both troubles for your nose and your bank balance. At this point, you will be wondering how much exactly your septic tank will cost to be replaced.
There is also no straightforward answer to how much your septic tank will cost to be replaced. A lot of the cost depends on why your septic tank needs to be replaced. There’s a chance that the replacement could be covered under your building insurance, meaning you only have to pay the excess – typically around £100. Which is much less than what you’d have to pay for a brand new septic tank for your replacement.