How to Fit MDF Cornice and Coving: A Step-by-Step Guide

Cornice, often called coving, covers the joint between the wall and the ceiling. This guide is for MDF cornice, which you cut with a mitre saw just like skirting and fix with adhesive and screws. In the video below our fitter puts up a run from start to finish, and the written steps follow the same order.

Before you start

The ceiling and walls should be sound, dry and free of dust. Expect the ceiling not to be level. Almost none are, and the first step deals with it.

Tools and materials

• A mitre saw, or a mitre box and saw deep enough for your profile
• Tape measure, pencil and a string line
• Two short offcuts of the cornice
• Grab adhesive, screws and a drill
• Wood filler and decorator's caulk
• A sturdy step or platform, so you aren't stretching

Step 1: Mark a guide line

Because the ceiling won't be level, don't follow it by eye. Hold an offcut in place at each end of the wall and mark its edge on both the ceiling and the wall. Pull a string line between the marks at each end. That line is what you fit to, so the cornice runs straight even where the ceiling dips.

Step 2: Measure each wall

Measure every wall on its own, along the line you marked, and check each figure twice before cutting.

Step 3: Cut the corners

Cut internal and external corners on the correct angle with a mitre saw. The usual method is to place the cornice upside down in the saw, with the edge that meets the ceiling flat on the saw bed and the edge that meets the wall against the fence. Cut a test pair from offcuts first and hold them up in a corner to check the angle before cutting full lengths.

Step 4: Apply adhesive and press into place

Apply adhesive to both contact edges, the one that meets the wall and the one that meets the ceiling. Press the cornice firmly into position along your guide lines.

Step 5: Screw it in place

Use screws as well as adhesive for a strong, permanent fixing. Countersink them slightly so the heads sit below the surface and can be filled.

Step 6: Fill, caulk and paint

Fill the screw holes with wood filler and sand them smooth. Run caulk along the joints where the cornice meets the wall and the ceiling to hide any small gaps. Let it dry before painting.

Joining lengths on a long wall

Join two lengths with an overlapping 45° joint, glued and fixed either side, the same way you would join skirting. Our guide to joining skirting boards shows the method.

Curved walls and LED lighting

For curved walls and bays, use flexible MDF cornice. If you want a soft glow of light round the room, our LED coving is shaped to hold an LED strip.

Choosing a profile

Browse our full range of MDF cornice. Profiles such as Torus come primed or unprimed, in 2.1 m and 4.2 m lengths. Browse modern cornice for clean lines, or Georgian and traditional cornice for period rooms. Our guide to Georgian interior mouldings explains how cornice, skirting and architrave work together. Fitting skirting as well? See how to fit skirting boards.