Flat paints are known for their low sheen and colorful finish. So, can you paint over flat paint?
You can paint over flat paint because it doesn’t have a protective or glossy finish that repels moisture. As such, paints will stick over it with ease.
However, its finish must be clean and in good condition before applying paint. That’s because filth, grease, oils, or scratches prevent the new coating from sticking properly.
If the finish is sealed, you must remove the sealer first before applying the new paint.
Paints stick well to flat paint because it doesn’t have a glossy or protective finish that repels moisture. So, all types of paint, including oil-based paint, will stick over it.
When dry, flat paint forms a textured dry finish that allows new finishes to stick over it. For a coating to stick, the surface must be dry and textured. This way, the paint will bite into the textured surface and stick.
However, if its finish is sealed, new paints won’t stick to it. That’s because sealants (such as polyurethane) form a glossy and protective layer over the finish that repels moisture. So, if you apply a new coating, the coating will slide off the glossy finish and won’t stick. To apply paint over a sealed flat paint, you must first remove the sealer.
Also, if the finish is dirty, wet, damaged, or chipping off, new paint won’t stick over it. That’s because the filth and moisture will prevent good adhesion.
Sanding is Necessary
You can paint over flat paint without sanding or priming, but only if the finish is clean and smooth. However, if the finish is damaged or rough, you must sand and prime it first.
If you don’t sand:
- Poor Adhesion – If the finish is damaged, no paint will adhere to it properly. You must repair it by sanding, priming, and in some cases, applying more coats of the flat paint for the paint to stick.
- Wet or Sticky Finish – If there’s poor adhesion between flat paint and the new coating, the finish will turn sticky.
- Terrible Protection – If you apply paint over a damaged finish, the new coating won’t stick and won’t protect the surface underneath. The new coating will peel off after a while.
How To Paint Over Flat Paint?
Here are the tools you need:
- Clean rags
- A cleaning solvent
- A pair of gloves
- A gallon of paint
- A bucket
1. Check If The Finish is Sealed
First, check if the flat paint is sealed with a topcoat or not.
To know if it’s sealed:
- Pour a few drops of water over the finish.
- Wait a few minutes.
- If the finish absorbs the water, the finish isn’t sealed.
- The finish is sealed if it doesn’t absorb the water.
Flat paint is water-based, and as such, it doesn’t repel water. So, if you apply water over it, its finish will absorb it. However, if the finish is sealed, the sealed topcoat will prevent moisture from penetrating its coating. So, the water will stay over the top layer.
If the finish is sealed, you must remove the sealant using a paint-stripping compound.
2. Sand The Finish
If the finish is smooth, even, and clean, you don’t need to sand it. But, if the flat coating is uneven, dirty, or has imperfections, you must sand it.
Sanding will remove the surface imperfections and leave behind a smooth, even (flat) surface for the new paint to stick to. Also, it will remove some parts of the flat paint and create tiny ridges for the new paint to stick. To sand flat paint, use fine-grit sandpaper.
If the finish has holes or cracks, you must apply 2 coats of oil-based primer.
3. Apply The New Paint
Once you sand and prime the flat paint, you can apply a new coating over it. Since flat paint is water-based, you can apply all types of paint over it. To apply paint over it, use a roller, brush, or sprayer.
Since flat paint is thin, you can apply up to 3 coats of paint over it. Each coat must dry properly before applying the next one.
4. Seal The New Finish
Optionally, you can seal finish with polyurethane or varnish. The sealers will produce a glossy layer over the finish and protect it from moisture, water, and scratches.
Types of Paint You Can Use:
Next, let’s check out a few paint types and see if you can use them over flat paint:
You can apply semi-gloss paint over unsealed flat paint because it sticks well to matte finishes. Also, flat paint doesn’t have a glossy finish that repels semi-gloss.
You can use satin paint over flat paint. If you don’t have a primer, flat paint can be used as a basecoat (primer) for satin. However, its finish must be clean and dry because satin is a semi-gloss paint, so stains and filth will prevent it from sticking properly.
You can apply eggshell over flat because they are both water-based, so they are compatible. You can even mix these two paints since none of the have sheen or gloss.
You can use high-gloss over flat. When dry, high-gloss forms a glossy finish, so you can use it as a sealer (or topcoat) for flat paint.
However, the finish must be clean because high-gloss reveals imperfections and damages of the surface once it dries.
Clear gloss can be applied over flat paint, but its finish must be clean and in good condition. That’s because clear gloss reveals stains and imperfections on the surface.
Also, clear gloss is thick, so you need to apply just one or two coats.
Since flat paint is water-based, you can use latex paint over it. You don’t need to sand it because latex paint will stick regardless. However, you must seal the finish because water-based paints aren’t durable.
Oil-based paint can be used over flat paint as long as the finish is dry, clean, and sanded. However, flat paints can’t be used over oil-based paints except if you remove the gloss from them first.