With her silky brown hair and well-groomed appearance, event organiser Cammie Chua, 23, looks the consummate professional.

What is not obvious is that she has hair extensions. They do not lengthen her shoulder-length hair, but incorporate subtle highlights of light brown and ash blonde.

She opted for this service at Hairdreams Couture Salon in Cuppage Road last month, because it was a way to try new hair colours in a conservative work environment.

Her job at a company selling luxury cars requires her to make a good first impression.

"I can't have loud colours in my hair, I have to look natural and presentable. It's a form of respect for our clients," says Ms Chua, who is married to a 25-year-old executive in the car rental industry.

While relatively few hairdressing salons in Singapore offer hair extensions services, those that do are reporting a rise in the number of clients seeking customised looks using hair extensions.

Traditionally, extensions are used to lengthen hair for people who have no time or cannot be bothered to grow their tresses out.

Hair extensions involving tightly braiding sections of hair can last three months or longer, while extensions tightened using metal micro beads may need repositioning every three months as hair grows.

Hair extensions can be made of synthetic hair, natural hair or a mix of both.

Now, more people are using extensions to thicken hair or to experiment with hair colour.

Mr Steve Koh, 29, style director at Number 76 hairdressing salon in OrchardGateway, says he has seen an increase of at least 20 per cent in the number of clients who want hair extensions.

"They don't necessarily want to make their hair longer, they use extensions for coloured highlights so they don't have to bleach their own hair," he says.

At his salon, he uses blonde tape in natural hair extensions, which he colours with on-trend hues such as blue, grey and purple.

Such extensions last about two months before the client is asked to return to the salon to ensure the extensions are still in place, as the client's hair has grown.

Each "bundle" of hair extension - a little patch about 2cm wide - costs at least $9.

The number of hair extensions used depends on the customer's preference regarding length, thickness or colour. The process of affixing 80 bundles of tape-in hair extensions, for instance, can take about two hours and cost about $720, he adds.

Another type of hair extensions is used at Hairdreams Couture Salon. It is made of human hair sourced from South Asia and Europe.

Hairdreams, which started partnering other salons early last year to use its proprietary Hair Creations system in Singapore, has seen a spike of at least 30 per cent in clients seeking customised hair extensions in the past year, says salon manager Yvonne Seah, 33.

Used in more than 10 other salons here, the Hairdreams system has a machine that affixes hair extensions using a kind of crystal polymer, which can last about six months.

To keep the extensions in good condition, customers should avoid using shampoos or hair products with alcohol or oil, which can loosen the hair extension bonds.

Hairdos involving hair extensions cost a few hundred to a few thousand dollars at Ms Seah's salon.

"People seek thickening extensions because their hair is thinning. Or they say, 'I want to change my look, but I don't want a drastic change,'" she says.

In such cases, she might advise clients against colouring their hair and to use highlighted hair extensions instead.

Ms Seah, who has 17 years of hairdressing experience, estimates that about 10 per cent of salons in Singapore offer hair extension services.

But these hair services are in demand due partly to the influence of social media and celebrities, and also thanks to the discreet nature of hair extensions these days.

Ms Jessi Timm, 34, director of The Parlour hairdressing salon in the Kovan area, says: "A lot of the pull has to do with Instagram, with bloggers with long, beautiful hair extensions."

She can take two hours to put extensions in and the service can even be done during customers' lunch break, depending on what they want. Thickening extensions is currently her most popular service.

Looking as if one's hair is natural, even with added colour, is important to many customers.

Operations manager Ms Teo, 50, who declined to give her full name, recently had black hair extensions put in for lengthening and thickening purposes.

"I don't want people to know I have extensions. My hair was thinning and I looked haggard. I want people to have the impression that I have naturally beautiful long hair," she says.

Mr Ivan Seah, 35, a freelance hairstylist based at Queen's Cut salon in Far East Plaza, says hair extensions provide instant gratification.

"Some people don't have hair that grows fast, but they want the length," says Mr Seah, who does not offer hair extension services, but sometimes styles and trims the hair of customers who have had them put in.

Ms Jae Wang, 23, a customer services executive, did not want to wait months for her hair to grow and put in lengthening hair extensions, extending her hair from mid-back to her waist late last month.

After experimenting with bleach and colours such as turquoise and silver in the past, her hair was in poor condition and some hair even broke when she combed it after the processed treatments. She opted for hair extensions to change her look.

Her braided hair extensions take some getting used to. For example, she is not able to comb all the way to the roots of her hair on account of the braids. But she is glad she has them.

"People didn't notice until I told them I had extensions. It looks natural and long. It boosts my confidence," she says.