Glass has a non-porous and slick surface; this makes it hard for paint to penetrate and stick. So, can you use chalk paint on glass surfaces?
You can use chalk paint for glass surfaces. However, you must clean the glass with a degrease to remove stains before applying it. Also, you must use chalk paint designed for glass surfaces.
Chalk paint has impressive bonding qualities and will stick to almost any surface. However, the surface must be clean and sometimes sanded before applying it.
Chalk paint sticks to glass surfaces if the surface is clean. However, you must use chalk paint designed for glass surfaces to get a better finish.
Since chalk paint is water-based, it will stick to any surface. In addition, water-based paints have impressive bonding qualities, dry fast, and are easy to apply.
However, if the glass is already painted or sealed, you must remove the existing finish first. That’s because chalk paint can’t stick to oil-based paints or sealers.
Optionally, you can wet sand the glass to improve the adhesion between the glass and paint. Sanding will create tiny ridges that the paint can penetrate into.
Related Read: Can You Use Chalk Paint on Plastic?
How To Apply Chalk Paint On Glass?
Applying chalk paint on glass is easy, but you must prep the surface to get good results.
Here are the tools you need:
- A Bottle Of Rubbing Alcohol Or Isopropyl
- Paper Towel
- A Sealant Or Clear Topcoat
- A brush (preferably a small brush)
- Chalk Paint
- Fine-Grit Sandpaper Or Sanding Block
1. Clean The Surface With Rubbing Alcohol
First, clean the glass surface with rubbing alcohol. Rubbing alcohol is a mild solvent that removes tough stains and grease from surfaces. You can use a degrease as an alternative to rubbing alcohol.
If you don’t clean it, the dirt and dust will prevent the paint from adhering properly.
To clean it:
- Pour rubbing alcohol or degreaser into a clean rag.
- Use the dampened rag to wipe the surface.
- Wait a few minutes (5-10).
- Use warm soapy water to remove the rubbing alcohol residue.
If you don’t remove the rubbing alcohol residue, the paint won’t stick. That’s because rubbing alcohol is a natural paint remover and won’t allow a new water-based coating to adhere over it.
2. Wet Sand (Optional)
Once the glass is clean, you can wet sand it. Sanding is optional, but it helps the paint stick better. Sanding creates small ridges (or scratches) on the glass surface that the paint can penetrate into.
To wet sand glass, use fine-grit sandpaper. The fine-grit sandpaper won’t damage the surface; instead, it will smooth it out for paint. Don’t use coarse or rough sandpaper, as you can damage the surface.
After sanding, clean the surface with warm water and let it dry.
3. Apply Chalk Paint
Once the glass surface is dry, you can paint it. You can use a sprayer or brush to apply chalk paint over it. A sprayer will provide a better finish quality and help the paint stick better. However, a brush allows you to apply thin coats without wastage.
To apply it:
- Apply 3-4 coats of chalk paint.
- Wait until one coat dries before applying the next one.
- Optionally, you can sand between coats.
Chalk paint dries fast since it’s water-based. It takes 30 minutes to dry between coats.
4. Seal The Chalk Paint If Needed
After you apply the chalk paint, seal it. A sealer, such as polyurethane, will protect the finish from moisture, water, and scratches. You can use water-based polyurethane for indoor surfaces. For outdoor surfaces, use exterior polyurethane as a sealer.
To seal chalk paint, apply 3-4 coats of sealant. Wait until one coat of sealer dries before applying the next one. Optionally, you can sand between coats of sealer (except for the final coat).
For indoor glass surfaces, sealing the finish is optional because indoor surfaces aren’t exposed to water or moisture. But, for outdoor glass surfaces, you must seal the finish as it is exposed to constant moisture and water.
Chalk paint is water-based, and as such, isn’t resistant to moisture, water, or scratches. If it’s exposed to constant water, it will get washed off.
Related Read: Does Chalk Paint Stick To Metal?
Chalk Paint Dry Time on Glass
It takes chalk paint 30 minutes to dry between coats, and 2 hours to dry fully (cure). Chalk paint dries fast because it uses water as its solvent, and water evaporates fast. Also, it has a thin flow, and the thinner its flow is, the faster the paint dries.
Also, since glass is non-porous, the paint won’t penetrate its surface and will start to dry immediately. This means chalk paint will dry faster on glass than on any other surface. That’s because its solvent (water) starts to evaporate immediately after you apply it.
The dry time depends on the room temperature, humidity, and the number of coats applied. For example, chalk paint takes longer to dry if the humidity levels are high. Also, the more coats you apply, the longer it takes to dry.
Related Read: How To Paint Over Chalk Paint?
Applying Chalk Paint on a Mirror
You can apply chalk paint to a mirror surface because the paint has impressive bonding qualities. However, you must use chalk paint designed for glass surfaces.
To apply it on a mirror:
- Use a synthetic or natural brush.
- Apply 2-3 light coats of chalk paint.
- Don’t apply too much force while applying it.
- Allow the finish to dry before using the mirror.
Chalk Paint Won’t Stick If:
Chalk paint won’t stick to a glass surface if the surface is dirty or painted. Dirt and dust prevent it from adhering and an existing finish will prevent the chalk paint from sticking over it.
Oil-based paints have a glossy finish that repels moisture, including paint. So, if you apply chalk paint over a painted glass, the paint will slide off the glass and won’t penetrate or stick.
If the temperature is lower than 50 degrees (F), the paint won’t dry and will remain tacky for several days. Also, if the humidity levels are higher than 50%, the paint won’t stick to a glass surface.
If the finish turns sticky:
- Wait until the finish dries.
- Sand off the bumps in the finish.
- Apply a new coat.
If the finish stays tacky for several days:
- Damp a clean rag into rubbing alcohol.
- Use the dampened rag to clean/remove the tacky finish.
- Re-apply it.
You can apply chalk paint on glass, but you must prep (clean) the surface before applying the paint. Also, you must use chalk paint designed for glass.
Tony is a professional painter and an author of DIY Geeks. Tony has completed over 1,000 painting projects for his clients. It's safe to say he knows what he Is talking about,