A massive open-plan kitchen and living space heated evenly

Open Plan Extensions

Massive spaces, perfectly even warmth.

Q: Can I combine kitchen plinths with wall skirting?

Yes, seamlessly. ThermaSkirt can be run along the wall as a traditional skirting board profile and then transition perfectly into a kitchen kickboard profile under the cabinets using standard connections. It acts as one continuous heating circuit.

Q: Will it cope with the heat loss from 5 metres of glass bi-folds?

Yes. ThermaSkirt emits heat very effectively. By surrounding the perimeter of the extension and utilising the kitchen island, you deliver a massive surface area of warm aluminium into the room to counteract the glazing's heat loss. Heated threshold kits are also available for door openings.

Q: Can I zone the open plan space differently?

If you plumb the kitchen run and the living area run onto separate legs of a manifold, you can use smart TRVs (like Heatmiser, Hive, or Tado) to control the temperature of the two zones independently.

Q: How does it compare to underfloor heating for extensions?

ThermaSkirt delivers comparable comfort (less than 1°C variance, BSRIA tested) but installs in 2–3 days with zero floor build-up, vs weeks of screeding and drying for wet UFH. It heats up in 10–15 minutes vs hours for screed-encased UFH. And critically for knock-throughs, it ignores the floor level differences between old and new builds.

Q: Does it work with heat pumps in open-plan spaces?

This is where ThermaSkirt excels. It retains ~48% output at heat pump flow temperatures (dT20), compared to ~30% for standard radiators. Distributed across 15–30 metres of room perimeter, it delivers more than enough output without the oversized 2400mm radiators that heat pump conversions usually demand.

Q: Can I add ThermaSkirt to supplement existing radiators?

Yes. Add2Rad connects ThermaSkirt in series with your existing radiators to boost room output at low temperatures. If your open-plan room needs 3kW but existing radiators only deliver 2kW at heat pump temperatures, you add 1kW of ThermaSkirt rather than replacing everything.

Q: How much does an open-plan installation cost?

An open-plan kitchen-diner typically costs £1,000–£2,000 depending on perimeter run length and heat demand. This replaces skirting, plinths, and radiators. Compare this to wet UFH retrofit at £15,000–£25,000 for an equivalent space.

Knocking through a Victorian terrace into a single open-plan kitchen-diner creates a stunning space, but a nightmare for traditional central heating. ThermaSkirt distributes the heat evenly along the entire perimeter, banning cold spots and freeing your expansive walls.

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<1°CTemperature variance across 40m²+BSRIA tested

0mmFloor build-up requiredvs 75–150mm for UFH

48%Output retained at dT20vs 30% for radiators

5 minHeat-up time from cold

Open Plan Skirting Board Heating

ThermaSkirt is a highly responsive radiant heating system tailored for large open-plan extensions. By acting as the room's skirting board or kitchen plinth, it operates exactly like continuous low-temperature wet underfloor heating (35–45°C), ensuring BSRIA-certified temperature gradients with less than 1°C variance across massive 40+ square metre rooms.

Heat Distribution

Solving the Point-Source Problem

The fundamental flaw with using radiators in open-plan living spaces is that they are point sources of heat. To warm a vast 8-metre long knocked-through lounge/diner, you are forced to deploy two massive double-panel convectors running at a scorching 70°C. Sitting near them is unbearably hot, while sitting in the middle of the room remains freezing cold due to aggressive convection drafts.

ThermaSkirt deconstructs the radiator and spreads its surface area horizontally around the entire room. Because the highly-conductive aluminium profile generates radiant heat at floor level across 10, 20, or 30 linear metres, the room is enveloped in a gentle cocoon of warmth. This is why independent thermal imaging confirms ThermaSkirt provides the exact same even comfort profile as premium, screed-encased underfloor heating.

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Bi-Fold Doors & Floor Changes

Seamless Integration with Modern Glazing

Large rear extensions often feature wall-to-wall bi-fold or sliding patio doors. This creates a secondary problem: massive heat loss exactly where you have zero structural wall to hang a radiator. Homeowners are often forced to install ugly, expensive trench-heaters sunk into the floor.

ThermaSkirt is incredibly versatile. It can be mounted directly onto the kitchen island kickboards, wrapped down the party walls, and even installed on short stub-walls next to the glazing. Crucially, if you are knocking through an old room into a new extension, ThermaSkirt installs completely above ground, ignoring the height differences and screed complexities of joining two separate floors, a nightmare scenario for retrofit underfloor heating.

Heat Pump Ready

The Ideal Emitter for Open-Plan Heat Pump Installations

Open-plan extensions are frequently the rooms where heat pump conversions fail. At 45°C flow temperatures, a standard radiator loses ~70% of its rated output. To compensate, installers are forced to recommend impossibly large 2400×600mm panels, heavy, visually intrusive, and often requiring structural wall reinforcement.

ThermaSkirt retains ~48% of its output at dT20 (vs ~30% for radiators) and distributes it across 15–30 linear metres of room perimeter. This eliminates the need for oversized radiators entirely. It can also work alongside existing radiators via Add2Rad, boosting room output at low flow temperatures without replacing anything.

Cost & Installation

Open-Plan Installation Costs

An open-plan kitchen-diner typically costs between £1,000 and £2,000, depending on perimeter run length and heat demand. This replaces both the radiators and the skirting board/plinths. Compare this to wet underfloor heating retrofit costs of £15,000–£25,000 for an equivalent space. For a detailed breakdown, see our cost guide.

Professional installation is recommended for open-plan spaces due to the longer pipe runs and plinth transitions. Our 120+ registered installers typically complete an open-plan project in 2–3 days. See our DIY or Professional guide.

"Every room is beautifully toasty and the top strip was replaced which makes the skirting look brand new."

Lisa Stevenson•Whole Home•

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Frequently Asked Questions

Everything you need to know

Can I combine kitchen plinths with wall skirting?

Yes, seamlessly. ThermaSkirt can be run along the wall as a traditional skirting board profile and then transition perfectly into a kitchen kickboard profile under the cabinets using standard connections. It acts as one continuous heating circuit.

Will it cope with the heat loss from 5 metres of glass bi-folds?

Yes. ThermaSkirt emits heat very effectively. By surrounding the perimeter of the extension and utilising the kitchen island, you deliver a massive surface area of warm aluminium into the room to counteract the glazing's heat loss. Heated threshold kits are also available for door openings.

Can I zone the open plan space differently?

If you plumb the kitchen run and the living area run onto separate legs of a manifold, you can use smart TRVs (like Heatmiser, Hive, or Tado) to control the temperature of the two zones independently.

How does it compare to underfloor heating for extensions?

ThermaSkirt delivers comparable comfort (less than 1°C variance, BSRIA tested) but installs in 2–3 days with zero floor build-up, vs weeks of screeding and drying for wet UFH. It heats up in 10–15 minutes vs hours for screed-encased UFH. And critically for knock-throughs, it ignores the floor level differences between old and new builds.

Does it work with heat pumps in open-plan spaces?

This is where ThermaSkirt excels. It retains ~48% output at heat pump flow temperatures (dT20), compared to ~30% for standard radiators. Distributed across 15–30 metres of room perimeter, it delivers more than enough output without the oversized 2400mm radiators that heat pump conversions usually demand.

Can I add ThermaSkirt to supplement existing radiators?

Yes. Add2Rad connects ThermaSkirt in series with your existing radiators to boost room output at low temperatures. If your open-plan room needs 3kW but existing radiators only deliver 2kW at heat pump temperatures, you add 1kW of ThermaSkirt rather than replacing everything.

How much does an open-plan installation cost?

An open-plan kitchen-diner typically costs £1,000–£2,000 depending on perimeter run length and heat demand. This replaces skirting, plinths, and radiators. Compare this to wet UFH retrofit at £15,000–£25,000 for an equivalent space.