BIAB has become one of the most requested treatments in Irish and British nail salons. The name is everywhere, but it is often confused with gel polish and shellac. Here is what BIAB actually is, how it differs, and who it suits.
What does BIAB stand for?
BIAB stands for Builder In A Bottle. It began as a brand name for a builder gel that comes in a bottle with a brush, rather than in a pot. Today people use "BIAB" loosely for any soft builder gel applied in the same way, in the same way that "shellac" has become shorthand for gel polish.
A builder gel is thicker than gel polish. Applied to the natural nail, it adds a thin layer of strength and lets the technician build a gentle curve (an apex) that helps protect the nail from breaking.
How is BIAB applied?
A typical appointment goes like this:
- Preparation: cuticles are pushed back and tidied, the shine is lightly buffed off the nail surface, and the nail is cleansed.
- Base layer: a thin layer of builder gel is applied and cured under an LED or UV lamp.
- Building: a second layer is applied and allowed to self-level, creating a smooth, slightly thicker structure, then cured.
- Colour: BIAB comes in clear, nude, milky and pink shades, and can be finished with gel polish colour or nail art.
- Top coat and cleansing for shine.
Because builder gel adds structure, BIAB can also be used to repair small breaks or add a little length.
BIAB vs gel polish vs shellac
| Gel polish / shellac | BIAB (builder gel) | |
|---|---|---|
| Thickness | Thin, like polish | Thicker, adds strength |
| Purpose | Colour and shine | Strength, protection, some shaping |
| Length | None | Small amounts possible |
| Typical wear | Around two weeks | Around three to four weeks |
| Removal | Soak-off | Soak-off or infill |
| Best for | Healthy nails, colour changes | Weak, bendy or breaking nails; growing nails out |
Shellac is the brand name of a well-known gel polish. In practice, "shellac" and "gel polish" both mean a thin, lamp-cured colour coat. Neither adds real strength.
BIAB sits between gel polish and extensions. It strengthens without the length or thickness of acrylic or hard gel. Our guide on gel vs acrylic nails explains the extension options.
Who is BIAB good for?
- People with weak, thin or peeling nails who want them to grow.
- Those who bite or pick, because a smooth, strong surface can make biting less tempting.
- Anyone who wants a natural, polished look that lasts longer than polish.
- People growing out acrylic extensions who want to keep some protection.
It is less suited to those who want very long, dramatic extensions.
Infills instead of removal
One reason BIAB is popular is that it can be infilled. Instead of removing everything at each appointment, the technician files back the top layer, fills the regrowth at the cuticle and rebalances the nail. Avoiding repeated full removal is gentler on the nail plate. Read how long BIAB nails last for more on infill timing.
Is BIAB bad for your nails?
Not when it is applied and removed properly. Problems usually come from aggressive filing during preparation, peeling the product off, or forcing it off with tools. If you want to take it off yourself, follow a careful soak-off method; see how to remove BIAB at home.
As with all gels, BIAB contains acrylates. A small number of people develop an allergy, especially if uncured gel touches the skin. Our gel nail allergy guide explains the signs.
Questions to ask in the salon
- Is this a builder gel or a gel polish?
- Will you infill at my next appointment or remove and reapply?
- Which lamp do you use with this product?
- How should I care for my nails between appointments?
Caring for BIAB between appointments
Builder gel lasts longest when the nails around it are looked after. Wear gloves for cleaning and washing up, use cuticle oil every day to keep the nail and skin flexible, and avoid using your nails to open cans or peel labels. If an edge lifts, do not pick at it; file it gently or ask for a repair.
How much does BIAB cost?
Prices vary from salon to salon and depend on whether you have a new set, an infill, colour or nail art. Most salons charge differently for a full set and a refill. Ask for a current price list before booking, and check whether removal is included if you are switching from another product.
Frequently asked questions
Is BIAB the same as gel?
BIAB is a type of gel, but it is thicker than gel polish and is designed to strengthen the nail as well as colour it. Gel polish and shellac are thinner and mainly add colour and shine.
Is BIAB better than shellac?
It depends on what you want. Shellac or gel polish is ideal for colour on healthy nails. BIAB is better if your nails are weak or break easily and you want them to grow.
Can BIAB add length?
A small amount. Builder gel can extend the nail slightly or repair a break, but for significant length an extension such as acrylic or hard gel is usually used.
Can you get BIAB on toes?
Some salons apply builder gel to toenails, though gel polish is more common for pedicures. Ask your technician what they recommend.