Priming (& Sealing) Chalk Paint: Is it Necessary?

Chalk paint has impressive bonding qualities. But, do you need to prime before applying it?

Chalk paint doesn’t need a primer to adhere to smooth, even, and clean surfaces. That’s because it has plasters in its formula that improve its bonding qualities. However, you need a primer if you are applying chalk paint on rough, uneven, and dirty surfaces. 

Chalk isn’t a self-leveling paint, so if you apply it over uneven surfaces (without a primer), the finish won’t bond properly and will crack after a while.

Types of Primer

You can use oil-based and water-based primer for chalk paint. However, chalk paint sticks best to water-based primer. That’s because they have the same solvent (water). 

Chalk paint won’t stick to sealed or waxed surfaces without a primer. A sealed (or waxed) surface won’t allow the paint to penetrate the surface and stick. If you apply it over a sealed surface, the paint won’t stick and will peel off. 

To apply chalk paint over a sealed surface, you must apply a shellac-based primer and then apply it. The shellac-based primer will provide a smooth layer for the paint to stick to. 

Also, you must use a shellac-based primer for damped, stained, or damaged surfaces. The shellac-based primer will prevent stains and moisture from bleeding through.

Without a Primer

You can apply chalk paint without a primer for clean, sanded, and smooth surfaces. Chalk paint has impressive adhesive qualities and will stick to any surface. 

However, for rough, stained, or sealed surfaces, you must apply a primer because it will cover imperfections and provide a thick (and smooth) layer for the paint to stick to. So, the paint will stick to the primer instead of sticking to the stained surface.

Before applying a primer, you must sand the surface. Sanding will remove imperfections and bumps from the surface and allow the primer and paint to stick better. If you don’t sand or prime the surface before applying it, the paint won’t stick properly and will eventually peel off (or crack).

Related Read: Can You Paint Over Chalk Paint?

Sealing Chalk Paint

You must seal chalk paint for outdoor surfaces because it isn’t durable and will wash off if exposed to constant water (or rain). Also, you must seal it for high-traffic indoor surfaces. If you don’t, the paint will be washed off from constant exposure to water, spills, moisture, and friction. 

The sealer is water-resistant, moisture-resistant, and UV-resistant. A sealer, such as polyurethane, will produce a thick glossy layer over the finish and protect it from water, moisture, and scratches. So, if the finish is exposed to water, the glossy layer of the sealer will prevent the water from penetrating it.

To seal it you can use:

1. Wax
2. Polyurethane
3. Varnish
4. Lacquer sealer
5. Wood glaze

To apply a sealer:

1. Wait for the paint to cure. 
2. Sand the finish with fine-grit sandpaper. 
3. Prepare the sealer. 
4. Apply 2-3 coats of sealant.
5. Allow the sealer to dry.
6. Once the sealer dries, the finish will be water and moisture-resistant.

You don’t have to seal chalk paint for decorative or low-traffic indoor surfaces. That’s because these surfaces won’t be exposed to water, moisture, or constant friction, so the finish won’t get removed. 

Related Read: Can Chalk Paint Be Tinted?

Using Chalk Paint as a Primer

You can use chalk paint as a primer (or undercoat) for any type of paint or sealant. That’s because chalk paint is water-based and has a dry textured finish that allows all paints to stick to it. 

Also, it has impressive bonding qualities because the paint is made of plasters. So, it will stick to any surface and provide a dry textured finish for other paints to stick. Chalk is mostly available in white and neutral colors that wouldn’t bleed through or cause stains underneath the top coat. 

Final Words

Chalk paint doesn’t need a primer for clean and sanded surfaces. However, for dirty, uneven, and sealed surfaces, you must apply a primer before applying it.

Also, you must seal chalk paint for outdoor and high-traffic indoor surfaces. But you don’t have to seal it for decorative surfaces.