As a beauty editor it’s my job to test beauty treatments but there are only a handful that I’m really obsessed with. Sure, there are tons of interesting ones out there, like laser facials and hair botox, but few are genuinely innovative and game-changing (the single most overused phrase in the beauty industry, in my opinion). 

Without a doubt, one of those innovations and my can’t-live-without product is builder in a bottle, which you may also know as BIAB nails. I’ll even bet money on you trying it and loving it. Here’s everything you need to know about the new nail treatment sweeping UK salons.

What are BIAB nails? 

BIAB (also known as builder gel) was developed by the brand The Gel Bottle. “It’s a gel nail enhancement designed to add strength and structure to your natural nails,” explains creative nail expert and content creator Sadie Jordan, “and to help them to grow out without breaking as easily.” Sadie adds that BIAB is more viscous than gel polish. “It allows you to build an apex — the highest part of a nail enhancement, most visible from the side angle — which is what makes your nail more durable.” 

BIAB is so versatile because you can use it to create a tip, which adds length to your natural nails, much like this style by @gellybeannails on Instagram. If long nails aren’t for you, you can also layer BIAB on top of your natural nail (whatever the length) to lend strength and prevent breakage. BIAB comes in many different colours but the most popular tends to be clear or neutral pink. It can be used as a base coat (with gel polish layered over the top) or applied on its own. 

What are the benefits of builder in a bottle? 

The main benefit of BIAB is the ability to grow your natural nails underneath. Even long-term nail-biters or those whose nails are prone to breakage have success with growth. What’s more, countless BIAB nail looks can be achieved without glue or plastic tips, says Sadie, which means you can have long-lasting manicures with the same removal process as regular gel. Another benefit of BIAB is that it can be used alongside nail forms (a paper or foil tip) to repair chipped corners.

What’s the difference between BIAB nails, gel nails and acrylics? 

It can be hard to tell but there are differences between the three. Gel nail polish was developed by CND under the brand name Shellac and is a liquid polish that is cured (basically hardened) under a UV lamp. Curing makes gel polish chip-resistant and gives it a longer wear. 

BIAB is a form of gel polish, which has a stronger base — this is why it assists growth. An upside of BIAB is that it can be soaked off just like gel polish. Both gel polish and BIAB give that incredible, long-lasting shine that regular nail polish can’t achieve, as you can see on these nails by @gel.bymegan on Instagram.

Acrylics are created using liquid monomer and powder polymer, which should be mixed carefully by your nail tech. Acrylics don’t need curing under a lamp and harden within a few minutes. If you’re someone who loves really long nails, acrylics tend to be a sturdier option than BIAB extensions. One similarity between BIAB and acrylics is that once the nail starts to grow out, you can get an infill (where product is applied to the nail growth area). 

So what’s the best technique? It all depends on your budget, what your nail tech offers, the outcome and length you’re looking for, as well as your activity level or how much you use your hands.

How long does BIAB last?

Luxury nail artist and beauty professional Charlotte Emily explains that most of her clients come in every three weeks to maintain their BIAB nails. But she noted that if there’s proper nail prep, a BIAB set can last for much longer. During lockdown, many of her clients’ nails lasted eight weeks, which she says is proof of the quality of the product. However, keeping BIAB nails on for this long isn’t recommended. After three or four weeks, BIAB nails can either be infilled or soaked off. 

Is there anyone who shouldn’t have BIAB nails?

Both Charlotte and Sadie noted that those with extremely damaged nails (for example very thin, extremely brittle and lifting away from the nail bed) shouldn’t get BIAB nails. In some cases, those with conditions like psoriasis may also want to avoid BIAB nails. “Applying BIAB directly to a severely damaged nail bed can cause heat spikes — a stinging sensation on the nail bed — and the product should not come into contact with skin,” says Sadie. A qualified nail tech will let you know whether you’re a suitable candidate for BIAB and can create a treatment plan that’s best suited to your nails. In fact, Charlotte said she’s never had to turn anyone away from BIAB nails. 

How much do BIAB nails cost? 

The cost of nails always depends on where you live, with city centres being the most expensive. The typical price range is £25 to £50. Charlotte charges £45 to £50 for a luxury manicure and includes BIAB as standard for her manicures in north Leeds.

Are there any downsides of BIAB nails?

“BIAB does take a little longer to soak off compared to gel polish,” says Sadie, but as long as the top coat is filed and broken down, this isn’t a major issue. “It can also make your nails grow out very fast,” she adds, “so you may need to have manicures more frequently if you don’t like the look of regrowth.” At present, BIAB has no downsides for Charlotte. “My clients and I are happy with the results and it has created a low-maintenance manicure which is great for a busy lifestyle,” she says.  

Where can you get BIAB nails in the UK? 

Although BIAB nails are becoming more popular, the treatment is not as easily accessible as gel polish so not every salon will offer it. Salons in London that offer BIAB nails include Paint, Shian Nails and Shoreditch Nails. Salons in Manchester that offer BIAB include Create and Coat and By Kristie Ltd. If you’re unsure, just call ahead and ask for the treatment specifically — you never know, high demand might influence the salon to offer it.

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