Milk Paint is non-toxic water based paint that you can make at home using just three ingredients: Make milk paint with milk, lemon juice and water, or simply buy ‘curd cheese’ or quark from a shop and start from there. DIY milk paint is biodegradeable, permanent, durable and non-polluting. Milk paints are the safest paints available and by using natural pigments (see our video) and a few other simple ingredients, you can make an interior paint of almost any colour, texture and finish.
Conventional paints contain pigment (the colour), carried by binders, solvents to help the paint application, and a dryer. Vinyl and acrylic paints include plastics compounds. You will rarely see all the ingredients listed on the tin. Some include formaldehyde, arsenic, thinners and foamers. They are harmful to both us and the environment.
Milk paint is typically used on porous surfaces such as:
Unlike oil or latex (emulsion) paints, you do not need to sand down the area or use a primer.
Use milk paint if you want a decorative finish with intense depth of colour and a low luster. Milk paint gives a mottled texture and is often used to achieve a “chippy” distressed look. When applied to a porous surface such as wood, milk paint sinks in and provides a breathable coating that will be resistant to chipping and peeling.
By adding some slaked lime or powdered chalk to the recipe you can improve the body of the paint and use it to paint over previously painted walls. Borax can also be added as a preservative giving the paint, if sealed and refrigerated, a shelf like for several weeks.
Milk paint generally has a matte finish (with a very slight sheen) and will show marks. Although it’s quite durable, it will be stained by many common kitchen substances, including oils. However, after the paint is dry, oil or our hemp oil soap can be rubbed in as a sealer. Once it sinks into a surface it is extremely difficult to remove, curing over time like concrete.
Normal paints are expensive – typically a litre of household costs in the region of £20, where as a litre of DIY milk using milk, lemon juice and water paint costs no more than £5.00.
Milk paint is quick drying. The first coat takes about one hour to dry. The process is even faster when you consider that using milk paint, the surface needs very little preparation and does not need priming. Again, this can represent another saving of money and time.
3. Reduce Pollution in Your Home
Normal paints contain solvents, and other volatile organic compounds (VOCs) which are toxic. The chemicals off-gas which mean they release dangerous vapours day and night. Prolonged or high exposure to paint and paint fumes can cause headaches, trigger allergies and asthmatic reactions, irritate skin, eyes and airways, and put increased stress on vital organs such as the heart. Babies and children should never sleep in a room painted with conventional paints. Non-toxic milk paint are safe for everyone in the household, especially for people with allergies, or with immune system problems or health issues live in the house.
4. Normal Paints Cause Significant Environmental Air Pollution
A typical oil paint can contain up to 50% VOCs and even a typical water based paint can still contain 3-7% solvents and these are a cause of air pollution, smog and cause global warming.
5. The Manufacture of Conventional Paints Puts Workers at Risk
Other chemicals in conventional paints include glycols, toulene, hydrocarbons, xylene, and ammonia. Mineral turpentine (used as a thinner and solvent) may contain up to 20% benzene, which is a confirmed carcinogen and mutagen in chronically exposed workers. The World Health Organization (WHO) has reported a 20%-40% increased risk of certain types of cancer (in particular lung cancer) for those who come into regular contact with, or who work with paint while Danish researchers point to the added possibility of neurological damage.
6. Pollution During Manufacture, Usage, Lifespan and Disposal
Even during the manufacture process these paints give off VOC’s and cardon dioxide, which contribute to air pollution and global warming. In the presence of nitrogen oxide, carbon monoxide and sunlight, the VOCs degrade into ozone and peroxyacetyl nitrate. Ozone from paint emissions irritates eyes, nose, throat and lungs; reduces breathing capacity even in healthy adults and children; increases susceptibility to infection, hospital visits and admissions. Ozone attacks lung tissue, and is very injurious, even in very low concentrations.
Even paints which are marketed as low VOC, contain up to 16g/l (GBCA) and ultra low to zero, 0-1g/l. Acrylic paints typically include a range of biocides to protect the latex, which can include arsenic disulphide, phenol, copper, formaldehyde, carbamates, permethrin and quaternary ammonium compounds. Vinyl and acrylic paints they will also include plastics compounds derived from petro-chemicals.
7. Difficulty of Disposal
When conventional paint goes off or remains unused, it is very difficult to dispose of. Most recycling centres don’t accept old paint cans unless they are completely empty.
8. Creativity is in Your Hands.
Be in creative control of the colour and texture of the paint in your house and have fun learning this life skill.
9. Breathable Paints are Better for your Surfaces
Milk paint is breathable and it helps to protect the integrity of walls made from traditional materials such as lime plaster, cob, brick and stone. Milk paints containing clays were used during the Crimean War to give hospital walls a healthy antimicrobial finish. Our blue indigo is also known for its antimicrobial properties.
10. Milk Paints Can be Used to Create a Myriad of Finishes
Milk paint is great for adding decorative textures and antique finishes to walls – take this further with sponge painting techniques, rag rolling, using a broad brush horizontally and then vertically to give a linen weave finish, colour wash etc.
Quark or curd cheese
Bowl and spoon
Cheesecloth or metal sieve
Sponge or brush
Step 1. Buy curd cheese of quark, the basis of the milk paint. My 250g pot of quark cost just £1.50.
Step 2. To help the paint bond better with your surface, mix 30g calcium hydroxide (hydrated lime)
with 35g of water and add this to the curds. Mix thoroughly. One way to do this is to force it through a metal sieve.
Step 3. To thicken the paint add 500-1500g of powdered chalk.
Step 4. Add pigments of your choice (see ideas below). Mix thoroughly, again using a sieve can help.
1 litre fresh milk (organic if possible) at room temperature.
The juice of one lemon, lime or white vinegar.
Both of these ingredients should be at room temperature.
Mix the milk and lemon, lime juice or vinegar together.
Leave at room temperature for 24 hours.
Strain through a cheesecloth for 2 hours or overnight.
The cheesecloth will now contain fresh curd or casein, the basis of your milk paint.
Rinse the curds with running water while still in the cheesecloth to remove any excess vinegar or lemon juice. We ended up with about 200g of curds!
a) To add more body to the milk paint,
Mix 30g calcium hydroxide (hydrated lime), and with 35g of water
CAUTION, wear gloves, an apron and eye protection because hydrated lime is corrosive. Once the paint is dry, it is completely safe.
b) Powdered 500-1500g of powdered chalk can also be used as a filler or thickener. Add this at the end of step 2.
Add the pigment and mix carefully.
Strain your paint mixture once more through the cheesecloth or metal sieve to ensure everything is well mixed and smooth.
The milk paint should be used on that day or it will keep for several days in the refrigerator, especially if you have added borax.
Mix natural dyes and earth pigments of your choice with the same quantity of water and combine with your milk paint.
For some ideas we used the following pigments in our video and they gave the following colours:
Cassia powder = mossy green.
Green Clay = beige.
Moroccan henna = umbre (orangey brown.)
Rhassoul clay = mushroom.
Indian Indigo = mid green.
Dyers Blue Indigo = intense blue.
Blackberries = initially a woad blue, but it faded to a pale blue with greeny streaks!
Mole hill soil = mid brown and very textured!
Bryony berry juice = initially a pale pink, but it faded to a cream colour.
You can add any water based colouring agent such as food colours and other natural pigments.
In our experiments, we found that a sea sponge helped with the mixing and we also used it for applying the paint instead of a typical nylon bristled paint brush. You can buy inexpensive ‘wonky sponges’ on our website. If you wash the sponge straight after use it can be used for other projects.
Stir your milk paint frequently as the chalk and lime rapidly settle and thicken at the bottom.
If you weigh your test batch of paint before and after and measure the size of your test surface, you will be able to calculate the coverage per square meter or foot. This will mean you can buy the right amount of ingredients and see your project through to the end.
Work up a test batch with your chosen pigments first and test paint your surface, allowing time to build up sufficient layers.
Our blue dyers indigo proved to give a stable colour and the best coverage.
Milk, quark, lemon, vinegar, borax – grocery shops and supermarkets
Chalk – art and craft shops, garden supplies shops, some hardware shops
Cassia, Moroccan Henna, Indian Indigo (green), Rhassoul Clay – in our natural hair department
Green Clay – among our dental range
Natural Dyers Blue Indigo – among our craft supplies
Wonky Sponges – our sponge seconds, ideal for crafts
Hemp Soap (oil proofing glaze)
PAINT POLLUTION HARMFUL EFFECTS ON ENVIRONMENT, by Tina Porwal