3. Fit the board Push the first board up into the adhesive.

4. Insert perimeter screws Secure the board along the perimeter with long drywall screws.

5. Insert concealed clips Secure the board to central brandering with concealed ceiling clips and small wood screws.

6. Repeat Measure, cut, fit and install subsequent boards, fitting them together using the tongue and groove along each length.

7. Cut and fit last board Secure with perimeter screws.

How to install the cornices

1. Mark guidelines Use a pencil to mark where the cornices will intersect in order to cut the correct angles.

2. Measure and cut cornicing to the required length.

3. Mark and cut angles Use a mitre-cut guide to cut the angles cleanly.

4. Apply adhesive and fit Apply a bead of adhesive to both edges, as well as the joint between the cornice pieces. Fit the boards into place.

5. Smooth and fill joints Smooth then remove excess adhesive using a damp sponge. Repair minor damage using Painters Mate or something similar.

To finish Paint the board with two coats of water-based paint or wood stain.

Project notes
  • Always use adhesive!
  • Always fix IsoBoard lengths positively to perimeter brandering on both ends.
  • Avoid butt joints: ensure the board runs from wall to wall.
  • Do not try to fill joints with plaster to create a skimmed ceiling look. Order the board with a bevelled edge or Isopine finish.