Underfloor heating in the bathroom – types, costs and key rules

Is it worth installing underfloor heating in the bathroom?

Underfloor heating in the bathroom is becoming a standard in modern houses and flats. The comfort of a warm floor after stepping out of the shower, even heat distribution throughout the room, or the ability to forgo unsightly wall radiators are just some of the benefits. It is no wonder that bathroom underfloor heating is gaining popularity even in smaller flats. Does it have only advantages? What are its potential disadvantages?

Advantages of bathroom underfloor heating

• Thermal comfort – a warm floor is pleasant to the touch, especially in winter.
• Even heating – heat rises from the floor over its entire surface, not from radiators.
• No radiators – more space for an aesthetic interior design.
• Fast heating – electric underfloor heating in the bathroom can warm up the floor within a dozen or so minutes.
• Moisture reduction – a heated floor accelerates the drying of towels and minimises the risk of mould growth.

Disadvantages and limitations

• Higher investment cost compared to a classic bathroom radiator.
• Necessity to plan the installation earlier, preferably at the renovation or construction stage.
• Installation limitations – there are places where underfloor heating cannot be laid for technical or safety reasons.
• Higher electricity consumption if you choose an electric system without a programmer and temperature control.

Types of underfloor heating for the bathroom

Two systems are most commonly used in bathrooms: water-based and electric. Although both have a similar goal, their construction and method of operation are completely different.

Water-based underfloor heating is installed mainly in detached houses. It ensures very cheap operation, but its installation requires significant interference with the floor structure.

Electric underfloor heating for the bathroom – installed in the form of mats or heating cables, ideal for renovations, flats, and small bathrooms. It reacts quickly to temperature changes and does not require a high floor build-up.

If you are wondering what types of underfloor heating exist, these two systems are used in 99% of cases in domestic bathrooms.

Underfloor heating in the shower – is it a safe solution?

Underfloor heating in the shower is an increasingly common practice, especially in modern bathing areas. When properly executed, it is fully safe – both in the wet and dry zones. Key factors, however, are the right materials, insulation, and the use of heating mats designed for such demanding conditions.

Underfloor heating in a walk-in shower

Underfloor heating in a walk-in shower acts not only as an element enhancing the comfort of using such a cabin but also prevents water from standing on the floor for a long time. In bathrooms where the shower is completely integrated with the floor, heating the spray zone facilitates water drainage and accelerates its evaporation.

Underfloor heating under a shower tray

In the case of shower trays, the matter looks different. If the structure is built-in, heating mats are installed next to the tray, not under it. If the tray is flat and flush with the floor, it is possible to install the system partially under it, provided the manufacturer allows it.

Underfloor heating under the bathtub – does it make sense?

Although technically possible, underfloor heating under a bathtub usually has no practical application. Heat is blocked by the casing or acrylic, and installation costs do not translate into real benefits. Most often, mats are only used in front of the bathtub, in the usable area.

Where not to lay underfloor heating in the bathroom?

The heating installation under the tiles should avoid places where there is no air circulation – there, heating will not be effective, and sometimes it can lead to overheating of equipment elements.

Safe and prohibited zones

Underfloor heating is not installed under:

• cabinets without legs;
• washing machines and dryers;
• free-standing bathtubs and classic built-in tubs;
• permanent fixtures mounted to the floor.

Minimum distances from sanitary ware and walls

For the system to work optimally, the following must be maintained:

• 10–15 cm distance from walls;
• minimum 20 cm from the toilet, bidet, and furniture housing;
• properly planned gaps between cables, especially in the wet zone.

Cost of underfloor heating in the bathroom – how much does it really cost?

The installation cost depends on the chosen system and the size of the room. How does the average cost look depending on the mentioned factors?

Electric heating mats in 2025 cost on average from 90 to 400 PLN/m² for materials and installation (mats, cabling, controller). In practice – especially in small bathrooms, where minimum labour costs are added – the real cost is most often around 200–350 PLN/m², and in premium variants up to approx. 400 PLN/m².

Water-based underfloor heating when installed throughout the house is currently 120–150 PLN/m² for labour and basic materials. In the case of a single bathroom (without a large area, with additional works, more difficult access), the cost may rise to 200–250 PLN/m², and with complicated floor layers even 300 PLN/m².

In a flat, the cost of the electrical installation itself is higher, but operation can be cheap thanks to programmers and zonal temperature control. A heated floor – bathroom in a block of flats – works great as an additional heat source, especially in winter.

Most common mistakes when installing underfloor heating in the bathroom

Installing mats in places where underfloor heating should not be laid due to safety reasons.

• Lack of damp-proof insulation.
• Too low cable density, resulting in poor efficiency.
• Installation without a temperature controller.
• Inappropriate selection of mat power for the room size.

Summary – when is underfloor heating in the bathroom the best choice?

Underfloor heating is ideal if you care about comfort, aesthetics, and even heating of the room. It will work well in new homes, flats, and small bathrooms where every centimetre of space counts.

Checklist No. 1: Is your bathroom suitable for underfloor heating installation?

• The floor will be renovated, or you have access to its structure.
• You have the possibility to perform damp-proof waterproofing.
• You want to increase the comfort of using the bathroom.
• You know where not to lay heating (under furniture, bathtub, appliances).
• You have chosen the type of system suitable for the flat (water-based or electric).

Checklist No. 2: What to remember during underfloor heating installation?

• Use mats and cables designed for wet zones.
• Maintain required distances from walls and sanitary ware.
• Thorough execution of damp-proof insulation.
• Installation of a temperature controller to save energy.
• Check the installation before laying tiles.

FAQ: Underfloor heating in the bathroom – types, costs and key rules

1. Is underfloor heating in the bathroom safe?

Yes, provided the installation is carried out in accordance with standards and using certified components. Special attention must be paid to damp-proof insulation and proper cable layout.

2. Can you install underfloor heating in the shower?

Yes, there are systems designed for installation in wet zones. However, it is important to use mats with increased resistance and tight waterproofing.

3. Can underfloor heating in the bathroom be the only heat source?

It can, if its power is appropriately selected for the square footage and heat loss of the room. In small bathrooms, it often replaces traditional radiators perfectly.

4. What to choose: water-based or electric underfloor heating?

Water-based works best in houses with a low-temperature heat source. Electric is ideal for flats and renovations because it has a quick installation and does not require raising the floor level.

5. How much does underfloor heating in the bathroom cost?

Electric systems usually cost 250–500 PLN/m² including the controller. Installing water-based heating is cheaper per metre but requires more construction work.

6. Does underfloor heating increase the floor height?

A water-based system raises it by a few centimetres. Electric mats raise the floor level minimally — most often by a few millimetres.

7. Can underfloor heating be installed under a bathtub or furniture?

No, because heat has no way to dissipate there. This can lead to overheating and damage to both the installation and the equipment.

8. Is underfloor heating expensive to run?

It doesn’t have to be — modern controllers allow energy consumption to be kept to a minimum. The key is the correct setting of heating schedules.

9. Can you install underfloor heating in a bathroom in a block of flats?

Yes, electric heating mats are most often used. They are thin, quick to install, and do not require changes to the central heating installation.

10. How long does underfloor heating installation take?

Electric mats can be laid in one day, and the remaining time is taken by finishing the floor. Water-based systems require more work and time for floor layers to be executed.