Hair Porosity 101


Porosity [por-ros-i-tee]

Your hairs ability to absorb moisture.

A measure of the voids (empty spaces) in a material, over the total volume of voids.

The state of being porous (having small holes that allow liquid to pass through).


It might sound a bit scientific Beauties, but bear with us and keep reading whilst we break it down. Armed with this knowledge you’ll get to understand your curls and kinks a bit better and be able to create effective routines. And who doesn’t want to get the best results from their products and their hair? (no hands should be raised here)

Put simply, porosity is ‘how many empty spaces you’ve got in your strand’ and thus ‘how well do your strands absorb and retain water’. Ta-da! And there you have it.

The science-y bit: The outer layer aka ‘the cuticle’ is formed of scale-like cells, which overlap and protect the inside of the strand. A bit like tiles on the roof of a house, which control the water that gets in. Some of our ‘tiles’ are packed really close together, not letting much water in, and other ‘tiles’ have bigger spaces in between that create space to let loads of water pass through. With the rest of us being somewhere in between. Actually, the tile analogy didn’t quite work out for that last bit, because no one wants a leaky roof. But we didn’t lose you right? Phew.

So, how do you know what kind of porosity you have and how it affects how to get the best from your kinks and curls? Easy! It’s a case of sink or swim…


Grab a glass of water at room temperature. Take two strands of CLEAN hair and drop into the water, watch for 2-4 minutes.


Low Porosity: Hair still floats after 4 minutes

Medium/Normal Porosity: Hair sinks slowly

High Porosity: Hair sinks quickly, almost immediately


Low Porosity Hair:

Sticking with our previous analogy (it works here, promise), if the tiles on your roof are really close together, your roof will not let water in when it rains, right? Water aka moisture has a hard time penetrating low porosity hair, because the cuticles are so tightly packed together. But the bonus with low porosity hair is, once you get that moisture in your hair will stay moisturised for longer because it’s just as hard to get back out. Low porosity Beauties will find that products and water droplets tend to sit on the hair more, and you might find colour “doesn’t take” or hair takes a long time to dry.

Targeted curl care for low porosity beauties:

– Be light-handed with products to allow for maximum absorption
– Use lighter leave-in products which can penetrate easier
– Apply heat when deep conditioning to speed up and aid absorption

BHB recommends:

CLEAN SLS Free Shampoo (£14)
DEEP Conditioning Clay Mask (£20)
MILK Leave In Moisturiser (£16)


High Porosity Hair

High porosity hair is the opposite. Your cuticles are loosely packed, so let in loads of water, which is great (initially). However, it lures you into a false sense of security that you can just do nothing, when in reality it loses just as much water as it absorbs and hair dries quicker than you can say “leave in conditioner”. But on the flip side, it also means you can achieve that extra puff and fluffiness on day 1 hair. Yay! High porosity Beauties will find that hair tangles easily because the cuticles are raised and snag on each other, so extra care should be taken when handling your curls and kinks.

Targeted curl care for high porosity beauties:

– Regular deep conditioning to lock in moisture
– Look out for more acidic ingredients like aloe vera to flatten cuticles
– Use rich butters that coat the strand and seal in all that moisture



BHB recommends:

MILK Leave In Moisturiser (£16)
WHIP Moisturising Butter (£20)
DEEP Conditioning Clay Mask (£20)


Normal/Medium Porosity Hair:

You’re good. There’s nothing more for you here…

Just kidding! We’ve got you Beauties too. But honestly, there’s not much to tell as you’ve got it pretty good. Your cuticles create the perfect space to let just enough moisture in, but are also close enough to limit what gets back out – which creates the perfect balance and needs the least amount of maintenance.


Targeted curl care tips for normal/medium porosity beauties:

– Occasionally add a protein treatment to your deep conditioning routine
– Avoiding proteins in daily leave on products
– Avoid over doing processes such as colour treatments and heat, as porosity     changes when the outer cuticle becomes damaged


BHB recommends:

CLEAN SLS Free Shampoo (£14)
WHIP Moisturising Butter (£20)
DEEP Conditioning Clay Mask (£20)



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Peace, Love & Curls


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