ThermoSphere Self-Adhesive Mesh 150W/m² Underfloor Heating Mat 4m² TSM-150-0400
- SKU
- EDDTSM1500400
Our Expert's Opinion
"A common pick for larger bathrooms and utility rooms. At 600W it sits comfortably on a standard floor thermostat."ThermoSphere 150W/m² Self-Adhesive Mesh Mat, 4m²
If you are tiling over a room and want warm floors without raising the floor level, this is the mat to price up. The ThermoSphere TSM-150 heats 4m² at 150W per square metre — a total of 600W — and sits in the tile adhesive at just 3.5mm thick, so the finished floor height barely changes.
At 4m² it suits a typical family bathroom or utility room. Measure the free floor area, not the room: leave out the space under baths, shower trays, kitchen units, and fixed furniture, then choose the mat closest to, but not over, that figure. The heating cable cannot be cut to length, so it is far better to go slightly under than over.
Why 150W/m²
150W/m² is the output most installers reach for in tiled rooms. It is enough to act as the primary heat source in a well-insulated room with most of the floor covered, and it warms a cold stone or ceramic floor quickly as a comfort system alongside radiators. For a poorly insulated room or a conservatory, look at the 200W/m² mesh instead.
How it installs
The fibreglass mesh is self-adhesive, so it rolls out and sticks straight down to a primed subfloor, wire side down. Turn the mat at walls by cutting the mesh — never the cable — and tile over it in a flexible adhesive. The cable is twin-conductor with a single 5m LayFlat cold tail, so there is only one end to bring back to the thermostat. Insulation boards under the mat make a real difference to warm-up time and running costs on a concrete slab.
It draws about 2.6A, so it sits comfortably on a 16A thermostat and a standard fused spur or dedicated circuit. A floor-sensing thermostat is required — it is what limits the floor temperature and keeps the running cost under control.
Warranty
ThermoSphere manufacture their mesh in Marden, Kent and back it with a lifetime warranty once the system is registered online. Register it straight after installation — it is the step most often missed.
Not sure which size to order, or which thermostat to pair it with? Call our team on 01934 253600 with your room measurements and we will work it out with you.
Specification
| Product code | TSM-150-0400 |
| Heated area | 4m² |
| Output | 150W/m² |
| Total load | 600W |
| Current | 2.6A |
| Voltage | 230V AC 50Hz |
| Mat thickness | 3.5mm |
| Heating cable | Twin conductor, FEP and HR-PVC insulated, earth screened |
| Cold tail | 5m LayFlat, single ended |
| Mesh | Self-adhesive fibreglass |
| Protection rating | IP68 — suitable for bathrooms, showers, and wet rooms |
| Max floor temperature | 27°C (recommended, limited by thermostat) |
| Warranty | Lifetime, on registration |
| EAN | 5056257300306 |
| MPN | TSM-150-0400 |
|---|---|
| Product Code | EDDTSM1500400 |
| Brand | ThermoSphere |
| Power (Watts) | 600 |
Delivery Information -
Standard delivery for all orders over £150 ex-VAT are free of charge.
If we can speed this up, we will, but you can also select Express Delivery when you check out and get your purchase more quickly (usually the next working day, subject to a 1pm cut-off): there is an extra charge for this ranging from £5 to £29.99 depending on the products you are buying.
We partner with several of the best UK carriers (such as TNT, Royal Mail, DPD etc) depending on the type of product and the warehouse it is coming from, and also with some pallet companies for larger items. All of these operate during normal Monday – Friday working hours, and we expect all deliveries to arrive in 5 days. For more details checkout this page.
Gledhill Cylinders – Delivery Charge -
For all Gledhill Cylinders, a flat delivery charge of £33.00 (ex-VAT) applies, regardless of order value or delivery method. This will be added automatically at checkout.
Returns Information -
Having to return a product because it doesn’t fit, or is not what you wanted, is really annoying! To try and make sure this isn’t necessary we have lots of helpful advice on our site, and you should feel free to call our experts on the number above to check if you are in any doubt at all – we’re always happy to help.
But if you do, don’t worry, just contact us and we’ll get it sorted (note that for trade customers there may be a restocking fee). If you need it, we can usually arrange the carrier to pick it up.
For full details of our policy, check out the small print here.
ThermoSphere 150W/m² Self-Adhesive Mesh Mat, 4m²
If you are tiling over a room and want warm floors without raising the floor level, this is the mat to price up. The ThermoSphere TSM-150 heats 4m² at 150W per square metre — a total of 600W — and sits in the tile adhesive at just 3.5mm thick, so the finished floor height barely changes.
At 4m² it suits a typical family bathroom or utility room. Measure the free floor area, not the room: leave out the space under baths, shower trays, kitchen units, and fixed furniture, then choose the mat closest to, but not over, that figure. The heating cable cannot be cut to length, so it is far better to go slightly under than over.
Why 150W/m²
150W/m² is the output most installers reach for in tiled rooms. It is enough to act as the primary heat source in a well-insulated room with most of the floor covered, and it warms a cold stone or ceramic floor quickly as a comfort system alongside radiators. For a poorly insulated room or a conservatory, look at the 200W/m² mesh instead.
How it installs
The fibreglass mesh is self-adhesive, so it rolls out and sticks straight down to a primed subfloor, wire side down. Turn the mat at walls by cutting the mesh — never the cable — and tile over it in a flexible adhesive. The cable is twin-conductor with a single 5m LayFlat cold tail, so there is only one end to bring back to the thermostat. Insulation boards under the mat make a real difference to warm-up time and running costs on a concrete slab.
It draws about 2.6A, so it sits comfortably on a 16A thermostat and a standard fused spur or dedicated circuit. A floor-sensing thermostat is required — it is what limits the floor temperature and keeps the running cost under control.
Warranty
ThermoSphere manufacture their mesh in Marden, Kent and back it with a lifetime warranty once the system is registered online. Register it straight after installation — it is the step most often missed.
Not sure which size to order, or which thermostat to pair it with? Call our team on 01934 253600 with your room measurements and we will work it out with you.
Specification
| Product code | TSM-150-0400 |
| Heated area | 4m² |
| Output | 150W/m² |
| Total load | 600W |
| Current | 2.6A |
| Voltage | 230V AC 50Hz |
| Mat thickness | 3.5mm |
| Heating cable | Twin conductor, FEP and HR-PVC insulated, earth screened |
| Cold tail | 5m LayFlat, single ended |
| Mesh | Self-adhesive fibreglass |
| Protection rating | IP68 — suitable for bathrooms, showers, and wet rooms |
| Max floor temperature | 27°C (recommended, limited by thermostat) |
| Warranty | Lifetime, on registration |
| EAN | 5056257300306 |
| MPN | TSM-150-0400 |
|---|---|
| Product Code | EDDTSM1500400 |
| Brand | ThermoSphere |
| Power (Watts) | 600 |
Delivery Information -
Standard delivery for all orders over £150 ex-VAT are free of charge.
If we can speed this up, we will, but you can also select Express Delivery when you check out and get your purchase more quickly (usually the next working day, subject to a 1pm cut-off): there is an extra charge for this ranging from £5 to £29.99 depending on the products you are buying.
We partner with several of the best UK carriers (such as TNT, Royal Mail, DPD etc) depending on the type of product and the warehouse it is coming from, and also with some pallet companies for larger items. All of these operate during normal Monday – Friday working hours, and we expect all deliveries to arrive in 5 days. For more details checkout this page.
Gledhill Cylinders – Delivery Charge -
For all Gledhill Cylinders, a flat delivery charge of £33.00 (ex-VAT) applies, regardless of order value or delivery method. This will be added automatically at checkout.
Returns Information -
Having to return a product because it doesn’t fit, or is not what you wanted, is really annoying! To try and make sure this isn’t necessary we have lots of helpful advice on our site, and you should feel free to call our experts on the number above to check if you are in any doubt at all – we’re always happy to help.
But if you do, don’t worry, just contact us and we’ll get it sorted (note that for trade customers there may be a restocking fee). If you need it, we can usually arrange the carrier to pick it up.
For full details of our policy, check out the small print here.
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