How much does a rainwater tank cost including installation

When you Google a rainwater tank, the first price you see is for the tank itself. For a five-cubic-metre plastic one, this is usually around thirty thousand Kč. However, the actual investment in a functional system is roughly four times that, and the difference isn't in the margin, but in everything that must be done to make the tank work underground.

Breakdown by item

A complete turnkey system typically costs 90 to 160 thousand KčThe tank itself accounts for roughly a third of this.

What drives up the price the most

Inaccessible plot of land

An excavator that cannot access the site is the most expensive item in the entire contract. If manual digging is required, or if machinery must be brought in via a neighbour's property or after dismantling a fence, add twenty thousand Kč and two days to the cost. For terraced housing and properties with narrow driveways, we address this immediately during the survey.

High groundwater level

It means a concrete slab under the tank, anchoring against uplift and often encasing in concrete. All three items at once. Where the groundwater is one metre below ground level, the difference compared to dry subsoil can easily be thirty thousand Kč.

Rocky or clayey subsoil

Skála means more digging and sometimes using a hammer on the excavator. Clay does not absorb water, so you cannot divert overflow into an infiltration pit; instead, you must connect to the sewer or construct a larger infiltration facility with soil replacement.

Water for the house, not just for the garden

The setup is simple: pump, hose, valve. Using it for flushing and laundry means a second distribution system in the house, separation from drinking water according to standards, automatic refilling when the tank is empty and finer filtration. This typically costs an extra fifteen to twenty-five thousand Kč - and is significantly cheaper in a new build than in a completed house where the distribution system has to be added later.

Where to save sensibly and where not to

Sensibly: A smaller tank volume if you won't use it anyway. A fill point instead of distribution throughout the house. Implementation outside the season: from autumn to spring, dates are more available. Preparing the route yourself (removing the fence, lifting paving slabs) where you have the capacity.

Unreasonably: omitting filtration (within a year you will have sludge and foul-smelling water in the tank), postponing the overflow ("we'll sort it out later" – meanwhile, water will find its way to the foundations), concreting where necessary, and using a cheap tank without documentation, this will cause you to lose the subsidy, which is many times higher than the few thousand Kč saved.

How to arrive at a specific figure

A fair offer is prepared after the site survey, which determines the groundwater level, access for equipment and the overflow route. Anything stated beforehand is an estimate based on similar jobs. We are happy to give it over the phone, but please do not treat it as a binding price. The difference between the estimate and the post-survey offer can easily be thirty per cent for this type of work.