Science & Performance
The easiest way to unlock low-temperature heating performance.
Add2Rad improves how radiators emit heat — making homes warmer, systems more efficient and heat pumps more viable in real-world UK housing stock.
🔥 The Science Behind Add2Rad
Traditional radiators waste a surprising amount of heat because of a cool boundary layer of air that clings to their surface. This slows convection, reduces useful heat output and forces systems to run hotter than they need to.
Add2Rad fixes that by altering the radiator’s thermal behaviour in three key ways:
🌬 1. Enhances Radiation
Add2Rad adds a high emisivity surface spread along the full length of the wall, enhancing the distribution of a systems radiated heat.
- Encourages faster, more even heat distribution.
- Targets the cold, damp, external corners.
- Helps the radiator deliver more useful heat into the room
Enhanced convection = more comfort at lower temperatures.
🧱 2. Reduces Boundary Airflow Resistance
Radiators normally lose effectiveness when:
- airflow is restricted behind furniture
- the room creates cold downdrafts
- the radiator sits in a boxed or recessed location
Add2Rad reduces the insulating effect of trapped air, improving efficiency even in difficult spaces.
🔥 3. Boosts Useful Heat Output
By improving heat transfer to the room:
- More of the heat generated actually reaches the room
- The system can maintain comfort at a reduced flow temperature
- Rooms feel warmer, faster, with less cycling
This is especially valuable for heat pumps, which depend on low flow temperatures for high COP.
📈 Performance Concepts
Add2Rad ties directly into the key metrics of modern low-temperature systems.
Lower Flow Temperatures
- Deliver improved comfort at 35–45 °C
- Reduce heat pump running costs
- Minimise boiler cycling and overshoot
More Stable Comfort
Improved convection leads to:
- fewer cold corners
- reduced draught sensation
- more consistent whole-room warmth
Reduced Cycling
A system that can meet demand at lower temperatures:
- stays on gently instead of spiking on/off
- increases emitter efficiency
- prolongs heat pump and boiler lifespan
🧪 Testing Summary
To verify these performance benefits, Add2Rad has been validated through:
Thermal Cycling
Simulates years of heat-up and cool-down behaviour to confirm:
- material stability
- long-term durability
- consistent performance
Output Benchmarking
Comparative tests examine:
- radiator output with vs without Add2Rad
- low-temperature emissions
- improvements in useful heat output
These findings support the system’s use in PAS 2035 and SHDF retrofit pathways.
🏁 Why This Matters
- Heat pumps perform best when radiators work at lower temperatures
- Boiler systems run more efficiently with steady-state convection
- Housing providers benefit from fewer radiator swaps and less disruption
- Residents enjoy better comfort without changing how they use their heating
Add2Rad makes existing radiators behave like emitters designed for the future — not the past.
For more detail, visit: