You just finished an amazing acrylic painting that you can’t wait to hang up outside – a bright, colorful abstract piece that will look perfect on your patio wall. Visions of dinner parties under string lights, as your guests admire your artwork, dance in your head. You haul the painting outside, nails and hammer in hand, excited to see it displayed…and then the skies open up. As rain pours down, you watch in horror as the acrylic paint begins to run down the canvas. “I thought acrylic was waterproof!?” you cry out in dismay.
Sound familiar? If so, you’re not alone. Many artists have fallen into the common trap of assuming acrylic paint is waterproof, when in reality, it’s only water-resistant. But all hope is not lost for your patio wall mural – with the right supplies and techniques, you can create acrylic art that will withstand the elements. Let’s dive into the details of how to make acrylic paint waterproof!
What’s the Difference Between Waterproof and Water-Resistant?
Before we get into acrylic paint specifically, it’s important to understand the difference between the terms “waterproof” and “water-resistant” in general:
- Waterproof means completely impervious to water – it can be submerged or soaked without damage. Water just beads up and rolls right off, leaving the material unchanged.
- Water-resistant materials can withstand water exposure to a certain degree, but not for prolonged periods of time. Water-resistant items may repel light splashes but can still be damaged by heavy rains or immersion.
So in summary, waterproof is the highest level of water protection, while water-resistant provides more limited defense against moisture. Keeping these definitions in mind will help set accurate expectations when working with acrylic paint.
Is Acrylic Paint Waterproof?
Now that we’ve got the terminology down, let’s get to the big question – is acrylic paint waterproof?
The short answer is no. Acrylic paint is water-resistant, but not 100% waterproof.
Here’s a breakdown of how acrylic paint behaves when wet versus when dry:
- Wet acrylic paint is soluble in water, so it can be thinned and washed away by moisture exposure. Raining on wet acrylic will dilute and ruin it.
- Dry acrylic paint forms a plastic polymer film as it cures. This makes it water-resistant – it will withstand light splashes and brief moisture. But heavy rains or immersion in water can still penetrate the paint film.
So acrylic paint gains water resistance as it dries, but is not impervious to water like a true waterproof material. At best, dried acrylic paint is water-resistant, not waterproof.
What Factors Affect Acrylic Paint’s Water Resistance?
Acrylic paint’s level of water resistance depends on several key factors:
Paint Quality
- Higher quality acrylic paints use stronger polymer binders that form a more durable paint film. Paints with higher resin content bond better.
- Student grade acrylics have less pigment and weaker polymers than professional grades. They’ll be less water-resistant.
- Avoid the cheapest acrylic craft paints for outdoor use, as they have minimal water resistance.
Surface Preparation
- Properly priming and sealing a surface makes acrylic paint stick much better so it’s less likely to wash away.
- Porous surfaces like canvas grip acrylic paint better than non-porous surfaces like metal or plastic.
- Smooth, glossy surfaces need to be sanded or etched for acrylic to bond well.
Environmental Factors
- Exposure to moisture, sun, heat, cold, and humidity will degrade acrylic paint over time.
- Using paints with UV-resistant pigments will help the colors last longer outdoors.
Maintenance and Storage
- Acrylic paint cured in overly humid conditions becomes weaker and less water-resistant.
- Storing acrylic paintings in very cold garages or hot attics hastens binder breakdown.
- Keeping acrylic art out of direct sun and moisture extends its lifespan.
How Does Acrylic Paint Hold Up on Different Surfaces?
Acrylic paint can be used on nearly any surface from paper to plastic, but its water resistance varies depending on the substrate. Here’s how acrylic hold up on some common painting surfaces when dry:
Canvas
- Acrylic bonds well to canvas’ absorbent, textured surface, making it water-resistant.
- Still needs to be varnished for outdoor use or risk damage from rain.
Wood
- Must be properly primed first so acrylic doesn’t soak into the grain.
- More coating layers = better protection.
- Should be sealed with polyurethane or varnish after painting.
Metal
- Very smooth so etch with sandpaper for paint to grip.
- Prime first, then add multiple paint layers.
- Seal with spray finish for outdoor metal art.
Rocks
- Acrylic adheres fine but lacks longevity outdoors if unsealed.
- Best sealed with spray sealants.
Concrete
- Prime first to prevent moisture problems underneath paint.
- Fully cure paint before rain exposure.
Plastic
- Can peel or chip off plastic without proper prep.
- Use a bonding primer so paint sticks tightly.
Glass
- Super slick so paint doesn’t bond well.
- Bake, coat with polyurethane, or etch surface first.
Ceramic
- Seal unglazed pieces so moisture doesn’t get underneath.
- Glazed ceramic is already waterproof.
Fabric
- Heat set with an iron or heat press to make fabric paint water-resistant.
- Add fabric medium to paint for flexibility.
How Can I Make Acrylic Paint More Waterproof?
Acrylic paint may not be fully waterproof, but there are several techniques artists can use to give their acrylic art much better water resistance:
Varnishing
Applying a clear acrylic varnish or spray sealant is the most common way to protect acrylic paint. Varnishing creates a protective layer that repels water while locking in the colors. Be sure to:
- Use an acrylic-specific varnish, not polyurethane or wood varnish.
- Apply in thin, even coats with a soft brush.
- Allow paint to fully cure first – never varnish wet acrylic.
- Apply at least 2-3 coats for best protection.
Epoxy Resin
Coating acrylic paintings in bar epoxy resin creates a glass-like waterproof seal. Often used for acrylic pours. The epoxy fully encapsulates the paint for a durable, plastic-like finish.
Baking
Heating acrylic paint between 225°F – 275°F can make it more water-resistant. Works well for glass, ceramics, and clay.
- Consult manufacturer’s instructions for proper baking temps.
- Allow painted piece to cool slowly to prevent cracking.
Fabric Medium
Adding textile medium to acrylic paint makes it more flexible and washable on fabric. Heat setting with an iron makes it water-resistant.
Priming
Using gesso or primer provides an extra layer of protection between the paint and the surface. It also gives the paint something to grip for better adhesion.
Surface Prep
Thoroughly cleaning and lightly sanding a surface prior to painting allows for maximum acrylic adhesion to avoid peeling or flaking later when exposed to moisture.
Curing
Allowing acrylic paint to fully air dry/cure for several weeks before water exposure gives the paint film time to reach maximum strength.
Proper Storage
Maintaining moderate temperature, low humidity, and UV-free storage slows the inevitable degradation of acrylic over decades.
What Are the Best Waterproof Acrylic Paint Brands?
Not all acrylic paints are created equal when it comes to water resistance. Here are some top-quality acrylic paint brands that offer good water resistance:
- Golden: Professional-grade with high pigment levels and archival lightfastness.
- Liquitex: Excellent adhesion and durability for professional artists.
- Winsor & Newton: Top-tier resin technologies for bright colors that last.
- Montana Cans: Specialty spray paint for long-lasting outdoor street art.
- Krylon: Contains UV-resistant polymers for protection against fading.
- Rust-Oleum: Formulated with oils for weather-resistant outdoor paint.
Acrylic Paint – Waterproof or Water-Resistant?
- Acrylic paint is water-resistant when dry, but not 100% waterproof.
- Quality paint, proper surface prep, and sealing make acrylic more durable.
- Varnishing, epoxy, and baking help safeguard outdoor acrylic art.
- Heat-setting gives acrylic fabric paint good water resistance.
- Priming and curing paint fully maximizes moisture protection.
So while acrylic paint alone can’t promise perfect waterproofing, there are luckily many ways to give your artwork an extra level of protection from the elements. Just don’t expect miraculous waterproof properties without taking the proper precautions. A little planning and preparation goes a long way in extending the life of your acrylic masterpiece!