How to Apply Epoxy Over MDF for DIY Countertops

How To Prep MDF for Epoxy Countertops

Step 1:  Build an MDF Substrate

Once you’ve measured the size and shape of your countertops, cut your sheets of MDF to size using a table saw or circular saw with a straight edge or guide. You’ll need to add a drop edge for all exposed edges (remember to account for your overhang), so use your MDF drops for 1.5” strips to attach along the underside. You can glue these strips in place with wood glue and clamps or speed the process along by using wood glue and a pin nailer. Make sure your drop edges are as flush as possible with the sheet of MDF.  

If the countertops are going to be anywhere with an opportunity for moisture to be in the air, like a humid bathroom or have splashes like around a sink, we recommend applying Red-Guard waterproofing membrane or a similar product to the bottom of the MDF panel.

Step 2: Create Countertop Edges

Countertop edge style comes down to personal preference. Decide if you want natural stone edges, a chamfer, bullnose edges, or a round-over. We recommend using Bondo to coat the edges first to hide any seams or, in the case of making a natural stone edge, a surface to shape to your preference. Once you apply the Bondo, allow it to dry, sand the edges smooth with 220-grit sandpaper, and shape with a router or sander according to preference.  

Step 3:  Prep & Apply Epoxy Undercoat

Clean the surface and make sure it’s dry. Apply two coats of Stone Coat Countertops Undercoat Epoxy directly to the MDF surface and edges. If you’re making a dark or colorful countertop, use Black Undercoat.  If you’re making a white or light countertop, use White Undercoat. If you’re in between, you can always mix black and white Undercoat to make a grey base.

Once the first coat is dry, apply a second coat and allow to dry.

Step 4:  Choose a Kit or Color Recipe and Get Pouring!

You Got This!