Why Homemade Laundry Soap is Bad For Long-Term Use

July 19, 2025
by Brodie Cook

You might think that homemade laundry soap is always safer and better for your health than commercial detergent. But that's not always the case. Homemade or DIY laundry soap has its downsides.

The downsides of using homemade laundry soap can leave a bad impact on your clothes, washing machine, and health. It might lead to controversy, as most people believe that homemade is always safe. But let's talk about the fact.

What Makes Homemade Laundry Soap Bad?

Basically, the homemade laundry soap or detergent has three main ingredients. These three ingredients have chemical characteristics that are beneficial for washing the laundry, but also harmful to your clothes.

1. Borax Sodium Tetraborate

You can find borax as the most used ingredient in the recipe for homemade detergent. It helps lift stains more effectively, gets rid of bad smells, and keeps the pH level in check while you wash. Borax can also function as a booster to help remove stubborn stains when combined with bar soap.

Borax works by raising the pH of the washing solution, making it more alkaline. This alkaline condition helps increase the effectiveness of soap in removing stains, especially those based on fat.

Borax also has the ability to bind metal ions such as calcium and magnesium in hard water, thereby helping to soften the water. In low concentrations, borax is also antiseptic and can help kill mild germs in laundry.

However, be careful if your homemade laundry soap contains borax. The Center for Environmental Health states that borax is harmful. In powder form, borax is easily airborne and can be inhaled or get into the eyes, which can irritate the respiratory tract, eyes, and skin. Repeated use without protection can also cause dry or itchy skin.

Besides, there were animal studies that showed that exposure to high doses of borax can disrupt the endocrine system, reproduction, and development. Although these effects have not been directly proven in humans, you must be aware of them.

2. Washing Soda (Sodium Carbonate)

Washing soda is also the most favourite ingredient in a DIY laundry soap recipe. It is super alkaline, meaning it is very basic, with a high pH. What is it used for? It helps dissolve stubborn stains, especially oily or protein-based stains such as food and sweat stains.

Besides, it helps neutralise minerals in hard water so that the soap is not overpowered by calcium or magnesium in the water. However, because it is so strong, it can cause skin irritation if you come into direct contact with it without protection.

On clothing, if you use too much or don't rinse thoroughly, it can make the fabric stiff or cause it to deteriorate quickly. So while it's powerful, its use must still be controlled.

3. Bar Soap

This is the star ingredient in many homemade soaps, bar soap! It is usually made from natural oils (such as coconut, olive, and palm) mixed with caustic soda (NaOH).

How's the result? Soap can remove grease and dirt because of its molecular structure. It has two sides, one that likes water and one that likes oil. So, dirt on clothes can be held by the soap and then washed away with water when rinsed.

Sounds good, right? But this soap has a major downside if you live in an area with hard water that contains ingredients like calcium and magnesium. The soap reacts with the minerals in the water and forms soap scum. This leaves white residue on clothes, dirty washing machines, and clothes that can smell musty or feel stiff. So, bar soap is fine if you use soft water.

The Disadvantages of Using Homemade Laundry Soap

1. Change the Origin Colour of Your Clothes

Have you ever noticed that your favourite clothes look dull after being washed several times with homemade laundry soap? At first, you'll see that your homemade laundry soap might work well. It removes stains from your clothes. But, month by month, you'll see a yellow spot in your clothes or even look dull.

How could that happen? That's because this DIY laundry detergent usually contains ingredients such as washing soda and borax, which have a high pH level (typically between 9 and 11.5), meaning they are very alkaline. If used too often, these ingredients can lift the dye from the fabric fibres, especially if the clothes are made of soft material or are light in colour. As a result, the colour of the clothes fades quickly or becomes patchy.

2. Damage the Fabric Fibres

Besides causing colours to fade, homemade laundry soaps can also damage fabric fibres. How is this possible? Because ingredients such as sodium carbonate (washing soda) and bar soap are very strong.

Think of it this way, they don’t just remove stains, but also gradually erode the fabric’s structure. If you keep using them, especially on delicate materials like spandex or thin cotton, the fabric can eventually become rough, tear easily, and even towels can lose their absorbency. So even though they look clean, your clothes are actually getting worn out from being constantly scrubbed with harsh materials.

3. Leaving Residue on Washing Machines and Clothes

Here's a common problem that you might not be aware of. The problem is residue. The soap bars are commonly used in a homemade laundry detergent recipe. It doesn't dissolve completely, especially if the water in your home is hard water. Hard water means that your water contains minerals.

This laundry soap can react with minerals and form a sticky white crust (scum). You can feel your clothes stiff, look dusty, and even smell musty, even after being washed. Besides, the residue can also leave soap buildup inside the washing machine.

The more residue and soap buildup, the riskier your washing machine is. It could damage your washing machine. You might save pennies, but it's not worth it if your clothes and washing machine are damaged.

4. Risk of Microorganism Growth (Bacteria & Fungi)

You might think homemade laundry soaps are clean and natural, but there's one thing that you'd forgotten. Mostly, the homemade laundry soaps don't contain preservatives. This means that, when you make the liquid version, the homemade laundry soap can become a breeding ground for bacteria and fungi. It becomes worse if it's stored at room temperature.

What's most dangerous? The soap becomes a breeding ground for microbes. If that happens, you’re not just washing your clothes, but also spreading bacteria throughout your laundry. This can be a problem for sensitive skin or baby clothes. You'd think that because you've a baby, you should use homemade laundry soaps.

5. Potentially Harmful to the Environment if Not Processed Properly

Many people think that using homemade detergent is always environmentally friendly because of its natural ingredients. However, this is not always the case.

Ingredients such as borax and washing soda can have a negative impact if they are disposed of directly into waterways without being treated. Borax, for example, contains boron, which can harm plants and soil microorganisms if it accumulates. Besides, a pH that is too high can disrupt the balance of aquatic ecosystems.

So, if you want to use homemade detergent to protect the environment, make sure your washing waste is also properly processed. Remember, it’s not just about the base ingredients.

6. Lead the Contact Dermatitis Allergy

You've come to the end. What makes homemade detergent bad is not only that it can damage your clothes and washing machine, but also it can trigger allergies. Because homemade detergent usually has a high pH and often leaves residue on clothes, your skin can react immediately.

Those who are prone get allergies are those with sensitive skin or children. Symptoms can range from itching, dryness, redness, to the appearance of a rash. It could be more severe if you use essential oils that are not suitable for you. Even though this soap is "homemade," you should still be aware of the risks before using it daily.

Homemade Detergent vs Commercial Detergent

You have a good intention in using homemade laundry is to protect the environment. But you've learned the risks behind homemade laundry. There is a choice right now, whether to continue using homemade laundry or mix it with commercial laundry. Commercial detergent isn't always harmful if you can understand the ingredients.

What if you're still worried about the safety of commercial detergent for your sensitive skin or baby? We've got an option. You can use the Lucent Globe Laundry Detergent Sheets. This detergent sheet is safer than homemade detergent or conventional detergent.

You can use a detergent sheet; simply put the sheet in your washing machine or bucket of water. Then, you'll see the result of it. It could remove your stubborn stains without damage to your clothes and the washing machine. It's safer and better for long-term use.

Curious about how homemade detergent, regular detergent, and Lucent Globe’s laundry sheets compare? Let’s break it down.

Aspect	Homemade Detergent	Conventional Detergent	Lucent Globe Laundry Sheets
Main Ingredients	Bar soap (fatty acid salts), borax, washing soda	Synthetic surfactants, enzymes, builders (e.g., zeolite, EDTA), bleach, fragrance	Sodium dodecyl sulphate, polyvinyl alcohol (PVA), starch, glycerine, glyceryl cocoate, trisodium citrate, saponins, fragrance, protease
Surfactant Type	Natural soap (anionics)	Synthetic anionic and non-ionic surfactants	Biodegradable surfactants (e.g., SDS) plus plant-based saponins
Enzymes	None	Often contains multiple enzymes: protease, amylase, lipase, cellulase	Contains plant-based protease
Hard Water Performance	Struggles in hard water (forms scum), unless washing soda is added	Designed with builders and chelating agents to prevent residue	Contains trisodium citrate as a softener and chelating agent
Residue & Dissolution	May leave residue, especially in cold or hard water	Low residue, easy to rinse	Fully dissolvable PVA base, leaves no residue
Cleaning Effectiveness	Good for light stains but not tough stains	Highly effective on tough stains and greasy residue	Effective for light to moderate stains, and protease improves protein stain removal
pH Level	Highly alkaline (pH ~10–11), can fade colours or irritate fabric over time	Formulated with balanced pH (typically 7–10)	Moderate pH, buffered by chelating agents
Skin & Environmental Impact	Natural but may irritate skin. Borax poses potential reproductive toxicity	Some variants are gentle on the skin, but may contain allergens and synthetic chemicals	Non-toxic, septic-safe, phosphate-free, and biodegradable; no harsh chemicals
Packaging	Typically, no packaging or reused containers	Mostly plastic bottles or refill sachets	Plastic-free, compostable cardboard packaging
Cost per Load	Very cheap (homemade ingredients)	Around $1 AUD per load, depending on the brand.	Around $0.32 AUD per sheet/load

When Can Homemade Detergent Be Used?

How about if you still want to use homemade laundry soap or detergent? In what situation can you use that homemade detergent? To prevent any downsides of the homemade detergent, here is a situation you can use.

When you have soft water (low in calcium and magnesium). If you have hard water, you can add a water softener to make it soft. When you're using soft water, the detergent dissolves properly and doesn’t form soap scum or residue on fabrics and washing machines.
When you're not washing delicate fabrics. Homemade detergent is suitable for cotton or linen, but not recommended for delicate fibres like wool, silk, or elastane blends.
If used in small amounts and thoroughly rinsed. It prevents soap residue from building up on clothes or in the machine.
When you're not using a high-efficiency (HE) washing machine.
Used occasionally rather than daily.
If liquid versions are stored properly with clean containers, airtight lids, and for short-term use only.
When no harsh or excessive ingredients are added.

We do however recommend ours as you don't need to go through the hassle and making your own that might cause more harm than good.