Ask How-To: Everything You Need To Know About Dry Hair

Hair Health

Ask How-To: Everything You Need To Know About Dry Hair

Strands drier than the Sahara Desert? Read on.


Maddy Koo

Hairhouse Senior Stylist


In this article
1. What causes dry hair?
2. What are the typical signs of dry hair?
3. What is ‘porosity’ and how does it relate to dry hair?
4. Ways to address dry hair
5. The difference between dry and damaged hair
6. A simple routine to manage dry hair

What causes dry hair? 

  • Hot styling tools: they’re responsible for some 10/10 hair looks, but they can also dry out your strands due to their heat which strips hair of its natural moisture. 

  • Incorrect haircare: products not formulated for your hair type are another leading dry hair cause. 

  • Too many washes per week: put down the shampoo! If you wash your hair too often (read: daily) it removes the natural oils resulting in dehydrated hair. 

  • Harsh chemicals: using sulfates or alcohol-based styling products can also strip the hair of its natural oils, leading to dryness.

  • Environmental conditions: overexposure to the sun, extreme heat and cold, and low humidity can all cause dry hair symptoms.

What are the typical signs of dry hair?

Hair that’s flat, dull, difficult to manage or has a brittle texture that tangles easily is in need of a big drink. If you also notice your hair isn’t maintaining a blow wave this can be a sign hydration is lacking. Then there’s the really obvious sign: split ends. Ugh! Depending on hair length, split ends are inevitable due to the hair cuticle's nature and the tendency for the older cuticle to shed from the cortex of the hair shaft. However, this should be happening to no more than a quarter of your hair ends. 

What is ‘porosity’ and how does it relate to dry hair?

When we talk about dry hair, the term ‘porosity’ is also thrown around – more specifically, your hair’s porosity levels – which indicate the cuticle’s ability to absorb and retain moisture. Knowing this will help you figure out much moisture your hair needs. High porosity is dry and needs the most moisture, whereas low porosity needs the least.

Turns out there’s a handy at-home test you can do to measure your hair’s porosity no matter your hair type. After you’ve shampooed, rinsed and dried your hair completely, take a single strand and drop it in a bowl of water. After letting it sit for up to four minutes, see if the strand sinks to the bottom of the bowl or floats at the top. Low porosity hair will stay on top of the water. Medium porosity hair will float and stay suspended in the middle. High porosity hair will sink to the bottom of the bowl. Funnest time you’ve ever had with a bowl of water, right? Now you’ve determined your hair’s porosity, picking the right product and treatment your hair needs to stay hydrated will be a breeze!

Low porosity hair has a tightly bound cuticle layer with overlapping scales that lay flat. If you’re in the low category your hair likely repels moisture when you try to wet it. It's also prone to build-up from deep conditioning products, making it feel stiff and straw-like. Opt for lighter, liquid-based products like hair milk that won't sit on your strands and leave them oily or greasy.

Medium porosity hair has a slightly looser cuticle layer allowing just the right amount of moisture to enter while preventing too much from escaping. If your hair floated and stayed suspended in the water then it’s likely your strands hold styles and colours with ease – lucky! Occasional protein-rich conditioning treatments to maintain hair’s hydration levels are a good idea.

High porosity hair has gaps in the cuticle due to damage. This means your hair loses moisture easily and also lets too much moisture in – leaving it prone to frizz. The aim of the game here is to restore hydration, like, yesterday. Layer on plenty of leave-in conditionerhair oil, sealer and hair butter (not all at once!) to help fill the gaps in your damaged cuticles – and help them retain moisture.

What are some ways to address dry hair?

Like most hair concerns, swapping out your shampoo and conditioner is a great first step – and easy to do. Use a shampoo and conditioner combination designed to infuse hair with moisture. By adding moisture molecules each time your wash, you’re helping to restore the natural moisture balance in your hair. There are plenty of hydrating duos to choose from at Hairhouse, our picks include Matrix BIOLAGE Hydrasource Shampoo and Conditioner: both products are inspired by the moisture-rich aloe plant which helps optimise moisture balance and prevent future damage and dryness. Sexy Hair also offers hydrating options with their Smooth Moisturizing Shampoo and Conditioner which harness citric acid to balance hair’s pH to improve its appearance, manageability, softness and strength. You could also try Kerastase’s Nutritive Bain Satin 2 Shampoo which is formulated with lipids to improve natural oil production, proteins to nourish and soften hair fibres, and iris rhizome extract to provide lasting nutrition which is vital for dry hair.

The next way you could help rehydrate dry hair is with a leave-in conditioner – look for one that contains hydrating ingredients that will lock in moisture. REDKEN’S All Soft Mega Rich Hydramelt is infused with aloe vera to hydrate, strengthen and lock in moisture all day long. Simply apply to damp hair prior to heat styling or air drying.

A deeply moisturising treatment is dry hair’s best friend – once a week is all you need to increase moisture levels and impart shine. Our pick is Maria Nila True Soft Masque. It uses a colour guard complex to protect and preserve colour from UV and environmental stressors like pollution; a standout ingredient is sunflower oil which helps hair retain moisture and reduce breakage. Coloured hair is often more prone to dryness, FYI.

ou may have heard of “slugging” in skincare (the technique of applying an occlusive product as the last step of your nightly routine) but did you know hair slugging also exists? Essentially it’s the process of running a few drops of hair oil through your scalp and massaging it in – repeat the process and then leave it in overnight if you can.

Dry vs. damaged hair – what’s the difference?

Dry and damaged hair are often confused for the same thing, but damaged hair needs protein to fortify damaged cuticles and deeply moisturising formulas to bring back elasticity and shine. On the other hand, dry hair needs deep conditioning and long-lasting moisture to bring back suppleness, elasticity and shine. And how can you tell the difference between damaged and dry/dehydrated hair? It’s time to grab another strand of hair – this time wet. Gently pull it at both ends and see if it stretches. If it’s able to expand by around a third and then return to its original length it’s a fair sign that your hair is healthy. If there is no give, your hair is likely damaged and needs a protein boost and some love. If the hair stretches but doesn’t return to its original length, then it’s dry and needs some moisture, stat!

A simple routine to address dry hair

There are plenty of ways to give your hair the drink it’s crying out for – here are a few you could incorporate into a routine.

Step 1: Swap in a hydrating shampoo and conditioner to replenish and hydrate your dry strands. 

Step 2: Incorporate an oil into your weekly routine – one that’s rich in omegas and argan will help to stimulate hair growth and soften brittle strands. Our pick is 
REDKEN’s All Soft Oil as it contains both of these ingredients plus a moisture complex that acts as a protective primer before heat styling. 

Step 3: Get into the habit of a hair mask once a week – it’s the perfect Sunday self-care activity. A mask does the heavy lifting when it comes to hydration and nourishment. 

Shop the look
1. Matrix BIOLAGE Hydrasource Shampoo and Conditioner

2. Sexy Hair Smooth Moisturizing Shampoo and Conditioner

3. Kerastase’s Nutritive Bain Satin 2 Shampoo

4. REDKEN’S All Soft Mega Rich Hydramelt

5. REDKEN’s All Soft Oil

6. Maria Nila True Soft Masque