Underfloor Heating FAQs

Underfloor heating (UFH) is a method of heating a room using a heat source installed beneath the floor covering, rather than a wall-mounted radiator. It removes the need for wall-mounted heaters entirely — particularly useful in a wet room or bathroom, where wall space is often needed for the shower, screen and fittings.

It's especially effective in a wet room or bathroom, providing warmth underfoot the moment you step out of the shower or bath.

A thin heating wire is embedded beneath the floor covering — typically within tile adhesive or a self-levelling screed — and connected to a thermostat that controls temperature and, depending on the model, timing.

Unlike a radiator, which loses much of its heat to convection, electric underfloor heating is largely radiant, so less warmth is lost through windows and ceilings. It also doesn't dry out the air the way a radiator can, so the room doesn't feel stuffy.

Yes. Although water and electricity are naturally a concerning combination, Warmup underfloor heating is designed and tested specifically for use in wet environments.

Each heating cable is built in layers: twin conductor wires (their magnetic fields cancel each other out, reducing interference), an inner fluoropolymer insulation layer, a copper Earth Braid sleeve that safely conducts away any fault current, and an outer fluoropolymer layer. Every cable is individually tested at 5,000 volts before it leaves the factory, and the product range carries BEAB approval along with ETL, CSA and CSAus marks.

For guaranteed safety, always have the system installed by an installer experienced with underfloor heating, with electrical connections made only by a qualified electrician.

Warmup are the market leader in underfloor heating, ISO 9001:2008 accredited, UK-based, and trading for over 23 years — with more than 2.1 million systems sold in over 70 countries. Their heating cable is amongst the thinnest on the market (1.8mm diameter), so it won't raise floor levels, and it's BEAB approved to the highest electrical safety standard for the category.

Warmup also run a technical support helpline available to every customer, seven days a week, and back their electric and wet underfloor heating ranges with a lifetime warranty plus a SafetyNet™ installation guarantee — if a system is accidentally damaged during fitting, Warmup will replace it free of charge, subject to terms.

As Warmup authorised retailers, Wetrooms Online can advise on the most suitable system and specification for your specific project.

Three electric systems, plus a dedicated wall-heating mat:

• Loose Wire System — an ultra-thin (1.8mm), flexible heating wire, best suited to irregular-shaped rooms where precise, custom-spaced installation is needed.
• StickyMat System (150w & 200w/m²) — the wire is pre-spaced and fixed to a self-adhesive glassfibre mesh, making it the fastest and most secure installation method for regular-shaped rooms. Suitable for new-build, retrofit and refurbishment projects.
• DCM-PRO System — a decoupling system with a self-adhesive underside that removes the need for a separate adhesive layer, up to 40% faster to install than a standard membrane, with the cable spacing adjustable to set the system's wattage.
• StickyMat 3D wall heating mat — a self-adhesive wall-mounted heating mat with built-in earthing, ready to use straight out of the box for warming cold bathroom or wet room walls.

All three Warmup electric systems — StickyMat, Loose Wire and DCM-PRO — are compatible with stone, tile, hardwood, laminate, engineered wood, carpet and vinyl, and are fully tested for use with Karndean and Amtico. See our Guide to Wet Room Flooring for how flooring choice affects your wet room tray options.

Underfloor heating spreads warmth evenly across the whole floor at a lower operating temperature, with no cold spots and no bulky radiator taking up wall or floor space. Key benefits include:

• Suitable for new-build, refurbishment and renovation projects
• Lower running temperature for the same perceived warmth, reducing energy use
• Zone-by-zone temperature control with a suitable thermostat
• No exposed hot surfaces or metal edges — a safer environment for children, older people or anyone at greater risk of injury
• No routine maintenance required

It can. Underfloor heating typically has quicker heat-up times than a central-heating system and runs at a lower temperature for the same level of warmth in the room, which can bring running costs down.

Actual savings depend on your home's insulation, energy tariff, and how well the system is controlled. Fitting insulation board beneath the heating system is one of the most effective ways to reduce running costs — properly insulating the floor can cut heat-up time significantly and lower overall running cost by as much as 50%.

This depends on room size, insulation, heat loss and the flooring finish used, but a tiled bathroom can typically reach a comfortable temperature in as little as 20 minutes with a properly insulated installation.

Recommended maximum running temperatures are around 27°C for wood, carpet and vinyl finishes, and around 29°C for stone and tile.

Via a thermostat. Choosing the right type is important for both comfort and running costs. Warmup offer three:

• Smart — Wi-Fi connected and app-controlled, using your phone's location to manage heating automatically for the greatest efficiency and savings.
• Programmable — set target temperatures and times, and the thermostat manages the rest; some models include Active Energy Management™ to help trim energy use further.
• Manual — simple on/off control at a set temperature, best suited to rooms with consistent, predictable heating needs such as an infrequently-used guest bathroom.

Browse the full underfloor heating thermostat range.

The StickyMat and DCM-PRO systems are both designed for a quick installation — StickyMat has the wire ready-spaced on a self-adhesive mat, while DCM-PRO's self-adhesive decoupling mat lets the installer set cable spacing (and so wattage) as they go.

The system should always be laid over an insulated surface for the best energy efficiency, and connected to the mains only by a qualified electrician.

We recommend it in all cases. Insulation board sits beneath the heating system and prevents heat being lost into the cold subfloor or void below — particularly relevant on suspended timber floors. With insulation board fitted, a warm floor can be reached in around 20 minutes, compared with over two hours without it, which in turn saves on running costs.

The StickyMat, Loose Wire and DCM-PRO systems all carry a lifetime warranty, backed by Warmup's SafetyNet installation guarantee — if the heating system is accidentally damaged during fitting, Warmup will replace it with the same make and model free of charge. Thermostats carry a 3-year manufacturer's warranty, with an optional upgrade to an extended lifetime warranty on selected models.