Sparks of 2026: # 10 Add2Rad
The retrofit breakthrough ready to unlock heat pumps in 2026
Add2Rad solves what many see as the biggest bottleneck in the UK’s low carbon heating transition: the venerable radiator. With roughly 25 million homes still relying on legacy radiators that are poorly suited to low flow heat pump systems, retrofit projects often stall because upgrading means ripping out radiators, lifting floors, and weeks of disruptive building work.
Add2Rad changes that calculus. Instead of swapping out radiators wholesale, it uses slim, high efficiency skirting level emitters, developed by DiscreteHeat and derived from the ThermaSkirt system, that connect directly into existing radiator circuits. That additional output, often up to 90 W per metre, can be enough to bring a home up to the heat output required for modern heat pumps operating at flow temperatures of around 35 to 45°C.
The advantages are immediate and tangible. There is no need to remove radiators, no need to lift floors, and no messy building work. Most rooms can be upgraded in under two hours, with a whole house often completed in around a day. That makes retrofit faster, cheaper, and far less disruptive than conventional emitter replacement.
For homeowners, landlords, and installers, Add2Rad offers a practical route to lower bills, improved comfort, and heat pump readiness without aesthetic compromise. For landlords and social housing providers, it addresses one of the hardest operational challenges in retrofit by reducing void time and avoiding the need to decant tenants during works.
Put simply, Add2Rad does not just make heat pumps possible for millions of UK homes. It makes them realistic.
Why this matters for 2026
As pressure grows to decarbonise housing, EPC requirements tighten, and heat pump deployment accelerates, Add2Rad looks like a missing link in the UK retrofit puzzle. By removing one of the most common practical barriers, it opens a credible path for large scale adoption in homes that would otherwise be written off as too hard or too disruptive.
That is why Add2Rad earns its place in our Sparks of 2026 list.
And there is more to come.
We have an exclusive interview with Ethan Wadsworth from DiscreteHeat on how Add2Rad came to be and where it is going next. Even better, we have direct feedback from installers on what this solution is really like to work with on site.
Find out more tomorrow. Subscribe for more.