Bathroom heating and ventilation buying guide
The best way to heat a bathroom depends on what you want to warm: the air, the floor or the towel. For most bathrooms the right call is a 3-in-1 ceiling unit, which combines heat lamps, an exhaust fan and a light, plus a heated towel rail. Add underfloor heating if the room is being tiled. A bathroom also needs to lose moisture, so a fan is part of the plan from the start, not an extra.
What each option does
| Option | What it warms | Best for |
|---|---|---|
| Heat lamps and bathroom heaters | The person under the lamps, with instant heat | Getting out of the shower into warm air |
| Exhaust fans | Nothing: they clear steam and damp air | Every bathroom, whatever else is installed |
| Heated towel rails | The towel | Dry, warm towels and less damp in the room |
| Underfloor heating | The floor | Cold tiles underfoot, in a bathroom being tiled |
Heat lamps and 3-in-1 heaters
A heat lamp is an infrared bulb in the ceiling. It heats the person and the surfaces under it instead of the whole room, which is why it feels warm straight away. A 3-in-1 unit puts the lamps, an exhaust fan and an LED light in one ceiling fitting. That is the usual choice for a bathroom where the ceiling has room for one opening, because a single cut-out does the work of three.
The 3 in 1 bathroom heater lights and bathroom heaters collections hold the full range. Two ranges show the differences that matter:
- The Martec Forme comes in 2 heat and 4 heat. It has a 45W turbo fan, 275W infrared lamps, a 10W tricolour LED, a back draft stopper and thermal overload protection. It moves 300 cubic metres of air an hour at under 40dB, takes 125mm ducting and suits small to medium bathrooms.
- The Eglo Vesuvius also comes in 2 heat and 4 heat. It has 275W E27 lamps, a 25W motor that moves 260 cubic metres of air an hour, a 6W LED and side ducting with a 1.5 metre duct. It suits smaller bathrooms.
Choose 2 heat for a small ensuite and 4 heat where more people use the room at once. Both ranges need a ceiling cavity of at least 200mm for the Forme and 250mm for the Vesuvius, so check the depth above the ceiling before you order. The Forme is IPX4 rated and comes with a cut-out template, and the Vesuvius has a 300mm by 300mm cut-out. A 4 heat unit of either range comes with a four-switch wall control.
The lamps are standard 275W E27 bulbs, and replacement heat lamps are sold in this collection. A Martec replacement lamp suits the Forme, Striker and Uno, has an aluminium reflective coating and is rated for 5,000 hours. Use one only in a heater where each lamp holder is rated up to 275W. The Eglo bathroom heating and Martec Forme collections keep each range together.
Exhaust fans and moisture
A fan removes the steam a hot shower produces. Left in the room, that moisture settles on mirrors, walls and ceilings and encourages mould and mildew. Heat without extraction leaves the room warm and damp, so a bathroom needs both.
Four specifications decide which fan fits:
- Duct size. Fans take 100mm, 125mm or 150mm ducting, and the new fan should match the duct already run through the ceiling.
- Airflow. The Martec Saturn Round 335mm moves 443 cubic metres of air an hour, and the Fanco Hybrid 250 moves 482 cubic metres an hour.
- Noise. The Fanco Hybrid 250 runs at 36 dB(A) and the Martec Saturn at under 45dB.
- Ceiling depth. The Saturn and the Hybrid 250 both need at least 220mm above the ceiling.
Both of those fans carry an IPX4 rating and include a back draft damper that stops cold outdoor air returning through the duct while the fan is off. Some fans include an LED light, and the Fanco Hybrid 250 comes with a lead and plug. The bathroom exhaust fans collection holds the full range, and the Martec Saturn and Fanco Hybrid 250 collections keep each range together.
Fans come in three layouts, and the layout decides where the noise and the bulk end up:
- Ceiling fans sit in the ceiling opening. The Martec Flow Round 265mm is 175mm high, takes 125mm ducting, moves 390 cubic metres of air an hour and has a side ducting outlet with a draft stopper.
- Wall and ceiling fans, such as the Fanco Dynamic, fit either surface. The 150mm model runs at 34 dB(A) and moves 280 cubic metres an hour. Its thin draft shutter limits backdraft but is not fully airtight, and a ceiling fitting needs enough roof space to run the duct above the fan.
- Inline kits put the motor in the roof space. The Fanco Designer 150mm moves 520 cubic metres an hour at 44 dB(A), comes with 6 metres of flexible duct and a frameless vent, and the inline fan needs 250mm of height. That keeps the noise and bulk out of the room.
A 3-in-1 unit already includes a fan, so a separate one is not needed. A separate fan is the right choice when the heating comes from the floor and the rail, or when you want a larger fan than a 3-in-1 unit carries. The Martec Saturn and the Forme both work with the Martec bathroom remote, which is sold separately.
Heated towel rails
A heated towel rail dries towels and keeps them warm. It does not heat the room: most rails here draw 30 to 250 watts, which is enough for a towel and not for the air in a bathroom. That makes a rail the partner to a ceiling heater, not a substitute for one.
The rail also helps with moisture. A wet towel left on a hook adds damp back to the room, and a warm rail dries it between uses. The heated towel rails collection breaks the range down by style, size, finish and voltage, and the controllers and thermostats and Thermogroup timers and thermostats collections match a switch or timer to the rail.
Underfloor heating
Underfloor heating warms the surface you stand on, and it leaves the wall and ceiling clear. For a bathroom the usual choice is an electric Thermonet mat at 200 watts per square metre laid under the tiles, run by a programmable thermostat with a floor sensor. Kits start at 1 square metre, so a small ensuite heats only the floor it has. A mat takes about an hour to reach temperature, so it suits a timer set ahead of the morning.
The heating goes down before the tiles, so the decision belongs to the renovation stage, not the finishing stage. The underfloor heating collection explains the choice of mat or cable in full, and the Thermogroup underfloor heating kits collection holds the kits. A dual controller can run the floor and a heated towel rail on separate schedules from one wall plate.
Matching the options to the bathroom
| Bathroom | A sound combination | Why |
|---|---|---|
| Small ensuite, one person at a time | A 2 heat 3-in-1 unit and a single rail | One ceiling opening gives heat, extraction and light, and the rail dries the towel |
| Family bathroom with several users | A 4 heat 3-in-1 unit and a larger rail | More lamps for the room, more bars for the towels |
| Bathroom being tiled in a renovation | Underfloor heating, a separate fan and a rail | The floor is open now, and the fan can be sized on its own |
| Finished bathroom with a fan and no heat | A heated towel rail, then a heat lamp unit if the ceiling can take one | The rail is the smallest job, and a plug-in rail needs only a power point |
Planning the order
Three jobs have to happen before the room is closed in, and the order matters:
- Ceiling. Check the cavity depth against the unit and run the duct before the plasterboard goes up.
- Floor. Rough in the conduit for the thermostat and the sensor before the tiles go down, and keep the mat clear of the floor under the vanity and the bath.
- Walls. Decide where the rail's cable and the switches sit before the wall is lined.
A shared timer or smart control helps in the same room. The room warms ahead of use, and the fan runs for a set period afterwards, instead of relying on separate manual switches for each fitting.
What is the best type of heater for a bathroom?
A 3-in-1 ceiling unit, because the lamps warm you immediately and the fan clears the steam in the same fitting. It suits most bathrooms, and the Forme and the Vesuvius both suit smaller rooms.
Is a bathroom heater worth it?
For cold mornings, yes. Heat lamps give warmth in the first minute, and a timer on the rail or the floor keeps the room comfortable without running all day.
How do I warm up a cold bathroom?
Start with the surface you stand on and the air you step into. A heat lamp unit heats the air for the minutes you are in the room, underfloor heating warms the tiles, and a rail leaves a warm towel waiting.
Outdoor heaters
This collection also lists outdoor heaters for patios. They are not bathroom products. The outdoor heaters collection keeps them together.
