Medium-density fiberboard (MDF) is a building component used for items in the home, like kitchen cabinets, bathroom vanities, bookshelves, baseboards, interior doors, and nightstands. With so many uses for MDF, cabinets and furniture will eventually wear down and become chipped, dingy, or dated-looking. Still, you can re-paint MDF professionally, even as a DIY, by following a few careful steps.
First, to get a smooth paint finish on MDF, you’ll need to lightly sand it. Then, seal the MDF before painting with primer to assure a smooth finish. Even if you build brand-new cabinets, shelves, and furniture from MDF, you can still use the same protocol—resulting in a professional finish without the contractor pricing.
Before You Begin
Painting MDF cabinets is not as straightforward as you may think. The product’s porosity can result in a rough, swollen, or distorted surface texture after painting. Also, the edges of the MDF tend to siphon up paint, no matter how much is applied.
By first treating the MDF with a conditioning product, like a primer, you can paint MDF just like you would a less-porous surface. The type of paint you use on MDF is also important. Oil-based paints will help you achieve the smooth finish you’re looking for. Water-based paints, on the other hand, are not suited for porous MDF, even after its sealed.
Finally, for a smooth finish, it is best to paint large surfaces of MDF with a roller. A foam roller, specifically, will give MDF the smoothest finish.
Surface Sealer
The large, flat surfaces of MDF are easier to paint than the edges because the compressed wood fibers form a tighter bond across the surface. It needs less sealing. Plus, you shouldn’t encounter large pits on the surface.
Use a one-step clear sanding sealer to condition the MDF before painting. Oil-based sanding sealers work well, but you can also use a water-based sanding sealer if you prefer.
Edge Filler
The edges of MDF can be conditioned with the same sanding sealer as you used for the surfaces. Because the edges are so porous, you’ll still need to apply multiple coats of sanding sealer and sand between each coat.
A better method is to fill the edges with an acrylic polymer-based filler. This filler requires only one or two applications and it takes care of the large pits that you sometimes encounter in MDF edges.
Safety Considerations
Always work in a well-ventilated area when using paints, fillers, or coatings. Wear latex gloves. When sanding, use breathing protection.
Source: The Spruce