Can you add something to emulsion paint to make it waterproof?

Yes, you can add a waterproofing additive to emulsion paint to enhance its water resistance. These additives, often available at paint or hardware stores, are specifically designed to improve the paint's durability against moisture. However, it's important to follow the manufacturer's instructions for proper mixing and application to ensure optimal results. Keep in mind that while this can improve water resistance, it may not make the paint completely waterproof.