Infrared heating is often misunderstood. This guide explains how infrared heats building fabric (not just air), why smart control avoids inefficient heat-down/heat-up cycles, and how “shadow” areas are still warmed—helping reduce condensation and mould risk.
How Infrared Heating Works
Infrared heating transfers energy directly into solid objects—walls, ceilings, floors, furniture, and people— rather than heating the air first. These surfaces absorb infrared energy and store it as thermal mass, then release it slowly back into the room, supporting stable comfort.
By comparison, many air-based systems primarily heat the air. Warm air can cool and escape quickly through ventilation, infiltration, and draughts—allowing the building fabric to cool faster than many people expect.
Why Fabric Temperature Matters More Than Air Temperature
Condensation forms when surface temperatures fall below the dew point—not simply when air temperature drops. A room can feel warm while corners and external walls remain cold, which is where moisture can condense first.
Because infrared heating targets surfaces and building fabric, it helps maintain higher, more stable surface temperatures—supporting comfort and reducing the conditions that lead to condensation and mould.
Why Infrared Heating Doesn’t Switch Fully Off
Allowing a room to cool to around 5 °C and then reheating it typically takes more time and energy than maintaining a stable background temperature (for example, around 14 °C). Reheating cold building fabric is slow because the fabric has thermal mass.
Well-designed infrared systems are therefore run to maintain stability rather than deep heat-down/heat-up cycles. This helps:
- reduce peak energy demand
- improve comfort recovery time
- keep surfaces warmer and more stable
- reduce condensation risk
What Smart Control Does in Infrared Heating
Smart control manages infrared heating continuously—modulating output to maintain a steady background condition rather than simply switching fully on or off. This supports stable fabric temperatures and avoids unnecessary reheating.
In practice, smart control improves efficiency by reducing temperature swings, lowering peaks, and helping keep room surfaces above the dew point in cold weather.
Will Infrared Heat “Shadow” Areas?
Yes—even without direct line-of-sight. Infrared panels heat the surfaces they “see” directly, but shadowed areas are warmed indirectly through:
- heat stored and released from surrounding warmed fabric
- natural air movement within the room
- conduction through walls, floors, and ceilings
With correct system sizing, placement, and background temperature control, the room’s fabric remains warm and stable—so shadowed zones do not remain “unheated.”
Does Infrared Heating Increase Condensation Risk?
No. Condensation is driven by cold surfaces. By maintaining warmer, more stable fabric temperatures—and avoiding deep cool-down cycles—infrared heating can reduce the conditions that cause condensation and mould.
Infrared vs Air-Based Heating (Quick Comparison)
| Air-based heating | Infrared heating |
|---|---|
| Heats air first | Heats fabric/surfaces directly |
| Heat can be lost quickly via ventilation/infiltration | Fabric retains warmth longer (thermal mass) |
| Fabric can cool rapidly when heating stops | More stable surface temperatures |
| Often relies on frequent reheating | Smart control modulates to maintain stability |
Performance depends on insulation, ventilation, system design, and control settings. Always size and place system appropriately.
Frequently Asked Questions
Does infrared heating warm walls and floors, or just the air?
Infrared heating primarily warms surfaces such as walls, floors, furniture, and people. The air warms secondarily through contact with these warmed surfaces.
Why does fabric temperature matter for condensation and mould?
Condensation forms when surface temperatures drop below the dew point. Keeping surfaces warmer and more stable reduces the conditions where moisture can condense and encourage mould.
Should infrared heating be turned fully off overnight?
Deep cool-down cycles can make reheating slower and less efficient because building fabric holds thermal mass. Many systems perform better by maintaining a stable background temperature.
Do “infrared shadows” stay cold?
No. Shadowed areas can warm indirectly through stored heat in the surrounding fabric, natural air movement, and conduction through building materials.
Does infrared heating increase condensation risk?
No. Condensation risk is driven by cold surfaces. By helping maintain warmer, more stable surfaces, infrared heating can reduce the conditions that lead to condensation and mould.