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I’ve been crafting my own soap for over 20 years now, and during all this time, I haven’t felt the need to buy soap from the store.

Recently, I decided to take my passion for natural products a step further by moving away from commercial shampoos. I’ve done this by crafting solid shampoo bars. The process is the same as soap, but with different ingredients that are better for hair.

I’m absolutely in love with this basic shampoo bar recipe I’ve been using. It’s beautifully simple and allows for so much creativity, especially when it comes to infusing oils with herbs.

For this recipe, I’m using olive oil that I’ve infused with rosemary, but I’ve also had great success with calendula, nettles, mint, and blends like rosemary mint. Each herb brings its own unique touch to the shampoo bars, turning every wash into a truly natural and personal experience.

The Difference Between Bar Soap for Body vs. Bar Soap for Hair

In the world of natural, homemade products, the distinction between bar soap for the body and bar soap for hair is a topic of much interest and importance. While many enthusiasts of cold process soap also use these bars as shampoo, it’s crucial to understand that hair and skin have different needs. To achieve the best results, a few key differences should be considered.

Tailoring the Recipe for Hair

The Choice of Oils: The formulation of a shampoo bar should differ from that of a body soap. This is because hair, unlike skin, requires a specific balance of oils and nutrients. When crafting a shampoo bar, the choice of oils is critical. Each oil contributes differently – some add moisture, some provide strength, and others contribute to overall scalp health. Additionally, the additives in shampoo bars should be chosen with hair in mind, focusing on ingredients that nourish and strengthen hair.
Superfat Percentage: Another aspect to consider is the superfat percentage. Superfat refers to the excess fat in the soap that is not saponified by the lye. In shampoo bars, this percentage might need to be adjusted to ensure that the hair is not left too greasy or too dry. Finding the right balance is key to a successful shampoo bar. This recipe is calculated at 5% superfat.
Vinegar or Citric Acid Rinse: After using a shampoo bar, it’s often recommended to follow up with an apple cider vinegar or citric acid rinse. This helps to balance the pH of your scalp and hair, leaving your hair smoother and shinier. It also assists in removing any soap residue, which can be particularly helpful in areas with hard water.
- - 1 cup vinegar (apple cider or white) to 2 cups water or
  - 1 tbsp. citric acid powder to 3 cups water

Personal Hair Compatibility: It’s essential to recognize that real soap might not work for everyone’s hair. Factors like the hardness of your water and your specific hair type play a significant role in how well a shampoo bar works for you. Some people’s hair might respond better to standard surfactant-based shampoos, and that’s perfectly okay. The beauty of natural hair care lies in finding what works best for you and your hair.

Why Use Homemade Shampoo Bars?

This DIY Shampoo Bar Recipe offers a variety of benefits that align perfectly with a lifestyle that values simplicity, health, and harmony with nature. Here’s why I like them so much:

Free from Harsh Chemicals: One of the primary reasons I switched to (and now make) shampoo bars is their clean ingredient list. They don’t contain sodium lauryl sulfate or other questionable ingredients found in many commercial shampoos. This means they’re gentler on your hair and scalp, and you’re not exposing yourself to potentially harmful chemicals.
Customizable for Your Hair Needs: When you make your own shampoo bars, you have the freedom to choose oils and ingredients that specifically cater to your hair type and color. This personalization ensures that your hair receives the exact nutrients it needs, whether it’s extra moisture, strength, or color protection.
Personalized Fragrance: There’s something deeply satisfying about being able to scent your shampoo bars exactly as you like. Using essential oils, you can create a sensory experience that resonates with your personal preferences. Whether you’re drawn to the calming scent of lavender or the refreshing aroma of peppermint, your shampoo bar can be a reflection of your favorite fragrances.
Travel-Friendly: Shampoo bars are a traveler’s best friend. Their solid form means they’re spill-proof, making them ideal for packing in luggage, especially when flying. They’re also space-efficient, as one bar can last as long as several bottles of liquid shampoo, reducing the bulk in your travel bag.

The Oils Used in this Recipe

Let’s explore the benefits of each of the oils used in this recipe and why they are chosen for making shampoo bars:

Olive Oil Infused with Herbs: Olive oil is a fantastic moisturizer for hair, rich in antioxidants and vitamins that promote scalp health and prevent hair damage. When infused with herbs like rosemary, it gains additional properties. Rosemary is known for stimulating hair growth and improving scalp circulation. Other herbs can add their unique benefits, such as nettles for strengthening hair or mint for a refreshing scalp treatment. This makes the oil a powerful ingredient in shampoo bars for nourishing and revitalizing hair.
Coconut Oil: Coconut oil is a staple in hair care due to its deep moisturizing properties. It penetrates the hair shaft, reducing protein loss and keeping hair strong and flexible. In shampoo bars, coconut oil helps create a rich lather and leaves hair feeling soft and silky.
Sunflower Oil: Sunflower oil is packed with essential fatty acids, including oleic acid and linoleic acid, which are beneficial for managing frizz and combating dryness. It’s also lightweight, making it a great oil for nourishing the hair without weighing it down. In shampoo bars, it contributes to a smooth texture and helps in conditioning the hair.
Castor Oil: Known for its hair growth-promoting properties, castor oil is a popular choice in hair care formulations. It also adds luster and can help in controlling hair loss. In shampoo bars, castor oil contributes to a creamy lather and helps in hydrating the scalp and hair.
Sweet Almond Oil: Sweet almond oil is a light, easily absorbable oil that’s rich in vitamin E, a natural antioxidant. It’s known for its softening and strengthening properties. It can help to smooth the hair cuticles, adding shine and making hair less prone to tangling. In shampoo bars, sweet almond oil adds a touch of luxury, making the bar more conditioning and gentle and is great in hair care products.

Each of these oils brings its own set of benefits to shampoo bars, creating a well-rounded and effective hair care product that caters to a variety of hair needs.

Before You Start: Infuse Your Oil With Herbs

Before diving into the creation of these nourishing shampoo bars, the initial step is to prepare a herb-infused oil. This oil forms the heart of the recipe, imbued with the natural benefits of herbs like rosemary or nettles, renowned for their hair-enhancing properties.

Begin by combining about one cup of olive oil with a quarter cup of dried herbs such as rosemary, nettles, or even mint. Allow this mixture to infuse in a cool, dark place for a minimum of two weeks, letting nature do its work.

If time is of the essence, you can opt for a quicker method by gently heating the oil and herbs on the stove top. Once the infusion process is complete, and you’re ready to make your shampoo bars, simply strain the herbs from the oil using a fine mesh sieve, and your herbal oil is ready to transform into a luxurious hair care product. Learn more about infusing herbs in oil here: How to Make Infused Herbal Oils the Easy Way

Using a Soap Calculator

For any recipe, you can adjust the ingredient quantities to fit the specific soap mold you have. Remember, all soap recipes are adaptable to the size of your mold.

To calculate the correct amounts, I recommend you use a favorite tool of mine, this soap making calculator from SBM Crafters. It’s super simple to use.

It’s crucial to note that whenever you alter a recipe, the amount of lye (sodium hydroxide) needed will change too. Therefore, employing a soap calculator is essential to determine the precise amount of lye required for your soap or shampoo bar batch. Never overlook this step, especially when tweaking a recipe or crafting one from scratch.

Just enter the ingredients and their quantities from this recipe into the calculator, then choose the ‘Resize your recipe to fit Any Mold‘ option and input your mold’s dimensions. The calculator will then provide the exact measurements needed for your specific mold, ensuring your soap turns out just right.

Here are a few of my favorite soap and lye calculators to help you easily find the one you like best:

Homemade DIY Shampoo Bar (Cold Process)

A word of caution: When working with lye in soap making, it’s crucial to exercise caution, as lye is a caustic substance. Direct contact with skin or inhalation can be harmful, so it’s important to wear protective gear like gloves and goggles and work in a well-ventilated area.

However, it’s also important to understand that lye is integral to soap-making. Through the saponification process, a chemical reaction between lye and fats or oils, lye is completely transformed. This reaction creates soap and glycerin, rendering the lye harmless in the final product. As a result, the finished soap bars are safe and gentle for use.

Equipment

Safety Goggles
Rubber Gloves
Kitchen scale
Glass Measuring Cups
Thermometer
Stainless steel pot for melting oils
Immersion Blender
Silicone Spatula
Soap Mold – This one is the perfect size to fit this recipe.
Freezer Paper for lining molds if not using silicone

Ingredients

9 oz coconut oil
9 oz olive oil (herb infused)
4 oz sunflower oil
3 oz castor oil
3 oz sweet almond oil

I had some rosemary-infused olive oil that I’d been saving to use in my shampoo bars, but plain olive oil would be fine. (Here’s how to infuse herbs in oils.)

Liquids and Lye

3.9 oz lye
8.9 oz water

Essential Oils

1 oz. essential oil of preference. I am using rosemary and peppermint

When it comes to adding essential oils to your shampoo bar recipe, the amount you use can vary based on personal preference and the strength of the essential oil’s scent. However, a general guideline for soap making is to use about 0.5 to 1 ounce of essential oil per pound of soap. Other essential oils such as lavender or tea tree are good choices.

Instructions

Preparation and Safety Gear: Put on gloves, goggles, and long sleeves for protection.

Weighing the Liquid: Measure cold water and pour it into a heatproof pitcher.

Weighing and Mixing the Lye: Next, weigh the lye. Gradually sprinkle and stir it into the water. Once mixed, place the solution in a safe area to cool down. (I do this outside to cut down on fumes).

Cooling the Lye Solution: Allow the lye solution to cool for 30 to 40 minutes until it reaches a temperature of about 100 to 110°F (38 to 43°C). To speed this up, you can place the pitcher in the sink filled with ice water.

Measuring and Preparing the Oils: Weigh the oils accurately. Melt the coconut oil in a stainless pot on the stove, then add in the other oils. This should warm the oil mixture to approximately 90 to 100°F (32 to 38°C).

Adjusting Oil Temperature: If necessary, gently warm the oils in a stainless steel pot to achieve a temperature between 90 to 100°F (32 to 38°C).

Combining Lye Solution and Oils: Carefully pour the cooled lye solution into the oil mixture. Mix them by alternating between hand stirring and using a stick (or immersion) blender until the mixture reaches ‘trace’.

Adding Essential Oils and Molding: Stir in the essential oils. Then, pour the soap mixture into a mold. You can use a spatula or the back of a spoon to create a design on the soap’s surface if you like. Cover it (I use a piece of cardboard) and insulate with a towel or blanket.

Setting and Cutting the Soap: Let the soap set in the mold for 1 to 2 days. Afterward, remove it from the mold and cut it into bars.

Curing the Shampoo Bars: Place the bars in an open area to cure for 4 to 6 weeks before they are ready for use. And voilà! You have made your very own shampoo bars.