Myvenusbeautysalon — A local beauty salon

How long does each service actually take?

A colour is 90-150 minutes, balayage is 2.5-3.5 hours and keratin is 2-4 hours.

A full-head colour is built from timed stages: 20-30 minutes to lift, 30 minutes developing, 15-45 minutes processing, then a rinse, tone and dry. Added together with application, the appointment lands between 90 and 150 minutes.

Balayage and other freehand lightening take longer because the product is painted on by hand, section by section: block out 2.5-3.5 hours. A keratin or smoothing treatment needs 2-4 hours, and that figure already includes the wash, the treatment itself and a 10-15 minute blow-dry at the end.

The wide ranges exist because hair does not behave uniformly. Hair lifts unevenly from root to ends, and roots on a previously lightened base take colour faster than virgin hair, so the same service runs shorter or longer depending on what is already on the head.

What happens during a full-head colour, minute by minute

Five timed stages, with two safety tests before any of them begin.

The developer is matched to the target depth before anything is mixed: 10 vol (3%) tones up to 10 levels, 20 vol (6%) gives 3-4 levels of lift and 30 vol (9%) gives 5-7 levels. Stronger is not faster in a useful sense — 30 vol left on the scalp for over 40 minutes is the main cause of irritation burns.

The named failures of a colour appointment all have clocks attached. An irritation burn comes from high-volume developer sitting too long on the scalp. Banding comes from skipping the strand test, because hair lifts unevenly from root to ends. Early fade comes from colouring over a previously lightened base, whose roots take colour faster and lose it sooner than virgin hair.

48 hours before: a PPD patch test goes on the skin; a reaction can keep developing for up to 72 hours after it appears.
Before the lightener: a strand test on a 5 x 5 cm (2 x 2 in) section, checked every 10 minutes.
Lift: 20-30 minutes with the developer matched to the target depth.
Developing: 30 minutes.
Processing: 15-45 minutes, then rinse, tone and dry.

Hair grows 1-1.25 cm a month, and that single number sets every return date in this guide.

Thirty-volume developer left on the scalp for over 40 minutes is the main cause of irritation burns.

The service file

How often do you need to come back?

Every interval is the same sum: 1-1.25 cm of new growth a month.

Colour has to be renewed every 4-8 weeks because new hair grows in without pigment. At 1-1.25 cm of growth a month, that is roughly 1-2.5 cm of visible root by the time the refresh is due. Roots on a previously lightened base take colour faster and fade sooner than virgin hair, so they sit at the short end of that window.

Cuts follow the same arithmetic. A fringe needs cutting every 4-6 weeks because even a centimetre of growth puts it in the eyes; a longer cut holds its shape for 8-10 weeks. A keratin or smooth finish is the long cycle: it holds a blow-dry for 3-4 months before it needs redoing.

Nails run on their own calendar. A full fingernail grows out in 4-6 months and a toenail in 9-18 months, and that growth rate is what sets how often a gel or shell manicure needs redoing as the bare nail emerges at the base.

The first 48 hours: what protects a new colour or smooth finish

What happens in the first two days decides how long the result holds.

The 48-hour figure is not arbitrary: it is the same window a PPD patch test needs before colour, and a skin reaction can keep developing for up to 72 hours after it first appears. The days around the appointment are when the scalp and skin deserve the most attention.

The biggest controllable risk is the shampoo bottle. Washing with sulfates strips a smooth or keratin finish in about three washes at 12-15 °C water temperature, turning a 3-4 month result into a three-wash one. Previously lightened roots fade sooner than virgin hair under the same washing, so the refresh interval shrinks too.

Skip sulfate shampoos: they strip a smooth or keratin finish in about three washes at 12-15 °C water.
Watch the skin: a PPD reaction can keep developing for up to 72 hours after it appears.
Expect previously lightened roots to fade sooner than virgin hair, and plan the refresh at 4-8 weeks.
Book the next visit before the finish fades: a keratin result holds 3-4 months, not longer.

Why the tests come before the colour

Because hair lifts unevenly and skin can react late.

A strand test is checked every 10 minutes on a 5 x 5 cm (2 x 2 in) section before lightener goes on the whole head. The reason is mechanical: hair lifts unevenly from root to ends, so the only way to know the timing for a particular head is to watch a small piece of it first.

A PPD patch test has to sit on the skin 48 hours before any colour. A negative test is not a lifetime pass — a reaction can keep developing for up to 72 hours after it appears — so the test is repeated rather than assumed.

One more scheduled return worth knowing: head lice live 7-10 days on the head, so a second treatment 7-10 days after the first is needed to kill eggs that had not hatched the first time. A single treatment leaves the cycle running.

Time in the chair, time between visits

Time in the chair and time between visits for the main salon services
Service	Time to block out	When you are due back
Full-head colour	90-150 minutes	Every 4-8 weeks
Balayage or freehand lightening	2.5-3.5 hours	Every 4-8 weeks, as unpigmented roots grow in
Keratin or smoothing treatment	2-4 hours	Every 3-4 months
Blow-dry finish within a keratin service	10-15 minutes	Holds 3-4 months if washed without sulfates
Fringe trim	—	Every 4-6 weeks
Longer haircut	—	Every 8-10 weeks
Gel or shell manicure	—	Set by nail growth: a fingernail grows out fully in 4-6 months

Time in the chair and time between visits for the main salon services

The numbers on the wall

Every figure shown here is a standard reference value: growth rates, processing times and test windows, not a measurement of any one salon.

The key terms of this guide, drawn to one scale

Where these numbers come from

The figures cited are standard industry reference values for hair growth, processing times and test windows, not measurements taken at any particular salon.