In short
- Heat damage occurs above 180°C on wet or damp hair; above 220°C on dry hair.
- Damage is cumulative — daily flat-ironing at 200°C compounds within weeks.
- Bond repair helps but does not fully reverse structural heat damage.
- Recovery requires temperature reduction, heat protectant, and patient growing-out.
Heat damage is different from bleach damage. Bleach breaks bonds chemically; heat cooks them. The resulting damage is largely irreversible — recovery is a combination of protecting what remains, supporting the cortex with bond work, and growing out the worst.
The temperature and moisture rules
- Never heat-style truly wet hair — steam damage is instant.
- Fine hair: max 160°C.
- Medium hair: max 180°C.
- Coarse hair: max 200°C.
- Curly/coily hair: max 190°C, and one pass only.
- Always use a silicone-containing heat protectant.
Recovery routine
Weekly bond mask, weekly hydrating mask (alternating), leave-in with silicone and ceramide, monthly salon trim. Reduce heat styling to twice a week maximum. Full visible recovery: 4–8 months.
When to cut
If more than 4–5cm of the length feels straw-like when wet, a graduated cut over 2–3 salon visits accelerates recovery more than any product routine.
The best heat damage repair is prevention. The second-best is scissors.
Frequently asked
Common questions
Do heat protectants really work?+
Yes — silicone-based protectants reduce cuticle damage by ~50% at moderate temperatures.
Are ceramic irons safer than titanium?+
Ceramic distributes heat more evenly. Titanium heats faster and hotter — riskier for fine hair.
Can I still get a keratin treatment on heat-damaged hair?+
Yes, once bond structure is stabilised. It smooths the cuticle and reduces the need for daily heat styling.
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