How Long Does Japanese Hair Straightening Last – And What Happens at New Growth?
Permanent on the hair it touches — but your new growth keeps its natural texture. Here's exactly what to expect long-term, and how maintenance really works.
What "Permanent" Really Means for Japanese Straightening
Japanese Thermal Reconditioning permanently restructures the internal bonds of the hair — the disulphide bonds that give your hair its natural curl or wave. Once those bonds are broken and reformed in a straight alignment, the treated portion of the hair remains straight. Forever. It does not revert. It does not gradually return to its natural texture over time the way a keratin treatment does.
This is one of the most important things to understand before booking the service. You are making a permanent decision about the hair that exists on your head today. That commitment is also what makes the result so liberating for the right clients — people who have spent years doing daily battle with a flat iron will genuinely walk out of the salon and never need one again on the treated lengths.
The nuance is new growth. Your scalp will continue producing new hair with your natural texture. This is what requires ongoing management — not the treated hair, which remains straight throughout its life on your head.
What Happens to New Growth After Japanese Straightening?
As your natural hair grows, new growth emerges from the scalp with your original texture. This creates a visible contrast at the root: natural curl or wave next to the permanently straightened treated hair. The transition line becomes more pronounced as growth accumulates.
This is normal and expected — it is not a flaw in the treatment. It's simply the nature of a permanent service on a naturally growing head of hair.
Managing new growth involves returning to the salon for a new growth application. Unlike a full re-treatment, only the new growth zone is processed — the already-treated lengths are not re-exposed to the solution. This makes new growth appointments both shorter and less costly than the initial treatment.
How Often Do You Need New Growth Appointments?
Most clients return every 4–6 months, depending on how fast their hair grows and how much contrast between their natural and treated hair they are comfortable with. Average human hair grows approximately 1.25 cm per month. A client with a notably different natural texture may prefer to return more frequently; someone with a looser natural wave might be comfortable waiting longer before the contrast becomes noticeable.
At Pierre Haddad Hair, we advise clients to track their own natural growth rate rather than adhering to a fixed calendar. Your stylist will help you determine your ideal maintenance rhythm at your initial appointment.
How Long Does the Initial Appointment Take?
Japanese Thermal Reconditioning is a multi-stage, precision service. The initial full treatment takes 4–6 hours depending on hair length, density and natural texture. This is not a treatment that can or should be rushed — the timing of the chemical solution, the temperature of the flat iron and the sectioning pattern are all calibrated precisely to your individual hair.
Pierre Haddad Hair has been performing Japanese Thermal Reconditioning since 2003, making the salon one of Australia's longest-running specialists in this technique. The experience behind that history is specifically relevant to this treatment — misjudgements in timing or temperature produce results that take months to correct.
How to Care for Your Hair in the First Week After Japanese Straightening
The first week after treatment is the most critical period for result preservation. The hair's restructured bonds are still setting during this time:
- Do not wash, wet, pin, tie or clip your hair for a minimum of 72 hours post-treatment
- Wear your hair completely down and loose for the first full week — any crease created while the hair is setting becomes permanent
- Avoid rain, sweat, steam and pools during the initial 72-hour window
- Switch permanently to a sulphate-free, sodium-chloride-free shampoo — both ingredients accelerate the breakdown of the treated structure
Following this care protocol is non-negotiable. Clients who skip the no-tie rule in the first week can develop permanent kinks in their straightened hair.
Read More at Pierre Haddad Hair
Frequently Asked Questions
Is Japanese hair straightening permanent?
Yes. The portion of hair treated with Japanese Thermal Reconditioning remains permanently straight. The treatment permanently restructures the hair's internal disulphide bonds — the new straight alignment does not revert over time. New growth (the hair that continues growing from your scalp) retains your natural texture and is managed through periodic new growth appointments, typically every 4–6 months.
How long does Japanese hair straightening treatment last?
The treated portion of your hair stays permanently straight. There is no gradual fade or reversion on the treated lengths. The maintenance requirement is managing new growth as your natural hair grows in — most clients do this every 4–6 months. The only limitation on permanence is the physical life of the hair itself: as treated hair grows and is eventually cut away over years, it is replaced by natural-texture new growth.
How long does a Japanese hair straightening appointment take at a salon?
An initial full treatment at Pierre Haddad Hair takes 4–6 hours depending on hair length and natural texture density. New growth maintenance appointments are shorter. Japanese Thermal Reconditioning is one of the most technically demanding services in professional hairdressing — the appointment cannot be rushed without compromising the result. Pierre Haddad Hair has been performing this treatment since 2003 and considers appropriate timing a non-negotiable part of safe, quality delivery.
What happens if I don't tie my hair after Japanese straightening?
In the first week after treatment, any crease, kink or indentation created while the restructured bonds are still setting can become permanent. This is why wearing the hair completely down and loose — without clips, ties, headbands or pins — is mandatory for the first seven days. A single night of sleeping with hair tied can create a bend that remains in the hair indefinitely.
How much does Japanese hair straightening cost in Sydney CBD?
At Pierre Haddad Hair, the Thermal Reconditioning treatment (Japanese-style) starts from $550. The Japatino Treatment (a premium variant) starts from $700. Pricing depends on hair length and density, and is confirmed at a complimentary consultation before any commitment is made. The salon is located at Shop 4, 255 Pitt Street, Sydney CBD. Pierre Haddad Hair has been specialising in Japanese Thermal Reconditioning since 2003.
Considering Permanent Straightening?
Book a complimentary consultation for Japanese Thermal Reconditioning at Pierre Haddad Hair, Shop 4, 255 Pitt Street, Sydney CBD. Your stylist will assess whether your hair is suited to permanent straightening and explain exactly what to expect — with a no-surprise quote.
