Heated floors: water-based or electric — honest price comparison

To ensure a fair comparison, one should consider not just the pipe and cable but the entire system: the base, installation, automation, wiring, power source, and potential repairs. Most importantly, it’s necessary to determine right away where the underfloor heating will be installed—whether in a regular apartment bathroom or throughout the entire first floor of a private house.

Let’s take a standard bathroom with an area of 6 m². Heating is usually not feasible under the bathtub, cabinets, and plumbing fixtures, so the usable space may be around 4 m².

If a heating mat with a power density of approximately 150 W/m² is used, the total installed power will be around 600 W. The mat can be placed on a layer of tile adhesive, so a new thick underlayment isn’t always necessary if the surface is flat.

The cost estimate will include:

• heating mat;

• thermostat and temperature sensor;

• preparation of the surface;

• waterproofing if needed;

• electrical installation and protective wiring;

• laying and connecting the components;

• tile adhesive and the tile covering itself.

For a small bathroom, such a project usually costs tens of thousands of rubles. If the foundation is already ready and there’s a suitable electrical line nearby, the expenses will be closer to the lower end. If a new line has to be run from the panel, along with redoing the flooring and waterproofing, the installation cost increases significantly.

This is exactly the situation where electric underfloor heating is convenient: the area is small, no complex collector is needed, and the temperature can be easily regulated separately from the rest of the apartment.

Now consider another scenario — the first floor of a private house with an area of 60 m².

Here, not only pipes are needed. The system includes insulation, damping tape, several circuits, a collector, fittings, automation, compression devices, and depending on the design, pump and mixing equipment as well. Usually, a leveling layer is applied on top, so its thickness and the future floor level must be taken into account during the design phase.

Approximately, a system for 60 m², including installation, can cost around 150–300 thousand rubles, though the boiler, final flooring, and some preparatory work may not be included in this amount.

In a space of 4–5 square meters, such a setup is almost always unnecessarily complicated. A collector and connections are needed in any case, so for just one bathroom, the water-based option rarely results in savings.

However, when a significant portion of the house is heated by underfloor heating, the equipment costs are spread over dozens of square meters.

For the bathroom in our example, the installed power is 0.6 kW. If the system is heated for a total of three hours per day: 0.6 kW × 3 hours × 30 days = 54 kWh per month. If the actual heating time increases to six hours, it will be around 108 kWh. To determine the cost, simply multiply the consumption by your electricity rate.

The cable does not have to run continuously. The thermostat turns off heating once the desired temperature is reached. The actual consumption depends on insulation, outdoor temperature, flooring, settings, and whether the floor is used solely for comfort or needs to significantly warm up the room.

In bathrooms, such consumption is usually manageable. For 80 m² with constant electric heating, the calculations need to be done with extra care.

The water circuit itself does not make heating cheaper. The cost depends on the heat source.

• If the house is heated by a gas boiler, the cost per kilowatt-hour of heat generated is usually lower than with direct electric heating. Heat pumps also work well with water floors: the system is designed for a relatively low temperature of the heat transfer fluid.
• If the water is heated by a regular electric boiler, the cost advantage may be minimal or non-existent. Electricity still has to be purchased; it first heats the water, which then heats the floor.

Therefore, for a private home, one first determines the heating source and the building’s heat loss, and then chooses the method of transferring heat to the rooms.

In a standard apartment, it is not allowed to connect the floor heating circuit to the central heating manifold on one’s own.

Such intervention alters the parameters of the indoor system: an additional circuit affects circulation and thermal balance, and thus potentially the heating of neighboring units as well. Modifying the heating system constitutes a renovation and requires compliance with established procedures. Therefore, the scenario of “taking hot water from the radiator and running it across the floor” cannot be considered a normal option for a standard apartment.

If one wants warm flooring in the bathroom, kitchen, or hallway, electric mats or cables are generally preferred in practice. A water-based floor makes sense only in buildings originally designed with such a system or where there is a legal independent heating system.

When comparing systems, people often focus on the heating elements and forget everything around them. For example, in an old apartment, uneven subflooring may be discovered after removing the tiles. In that case, the cost of an electric heating mat will include leveling, waterproofing, and a new layer of finishing.

In a private home, a water-based floor may require:

• insulation;

• a new subflooring layer;

• a distribution manifold;

• a cabinet for it;

• automation controls;

• setting up the circuits.

This is why two quotes for the same area can differ by a factor of several: one only includes the equipment, while the other covers the fully finished floor. Before signing the contract, it’s useful to ask the contractor to show what exactly is not included in the price per square meter.

After finishing, both systems end up hidden under a covering.

• In the case of an electric floor, the most affordable part remains the thermostat. If the cable itself is damaged, the faulty area must be located first, after which the tile or other covering needs to be locally removed.
• In a wet floor system, the collector, actuators, and pumping equipment remain accessible, while the pipes are located inside the floor. Therefore, the circuits must be checked thoroughly before pouring, and the collector cannot be completely hidden behind finishes.

For both systems, it’s advisable to keep photographs and layout diagrams. They will be useful in a few years, for example, when it’s necessary to drill through the floor or locate a damaged area.

Here, it’s simpler to divide the options into four scenarios.

• Standard apartment with central heating. Electric underfloor heating is more practical for the bathroom, kitchen, or hallway. It doesn’t interfere with the building’s overall heating system, takes up less vertical space, and is easier to control.
• Apartment with a separate, independent heating system. A water-based option can be considered, especially if the design includes such a system. But for a small bathroom, electric underfloor heating is often simpler and cheaper to install.
• Private home, underfloor heating only in the bathroom or hallway. If it’s just a few square meters, electric underfloor heating is usually more sensible—there’s no point in building a separate water system for such a small area.

Therefore, there is no universal answer such as “water-based is cheaper” or “electric is more cost-effective.” For a small area, cost and ease of installation are most important, while for a large house, the cost of heating over many years matters. It makes sense to compare these two scenarios rather than just the price per meter of pipe and heating cable.