Q: How do I cut and treat tegular edges for mineral fiber and fiberglass panels?

A: Field Tegularization

Let's look at the knife angle recommendation. Keep the blade sharp and on a sharp downward angle. This way, more of the blade edge is doing the cutting which results in a smoother edge. Tegular cut can be made on a flat surface:

  • Lay tile and knife on table
  • Slide knife along edge to cut


Another way of making tegular cuts is to use your finger as guide.

Fitting Board
For accuracy and simplicity, we recommend the following:

  • Cut the tegular board the same size as a regular board and lay it in position.
  • With a pencil, mark the face of the tegular board along the molding edge. Or, scribe the wall molding with a knife.
  • Remove the board, and with a sharp knife, cut along the pencil line halfway through the panel. Then run the knife blade down the edge of the panel in order to achieve the tegular detail.

Coloring Cut Edges Where Necessary
Naturally, it is not necessary to paint edges of boards along the perimeter walls as it is impossible for the eye to get close enough to see the raw cut. However, there are those situations where the cut edges will be visible and should have a factory-type finish. For these situations, refer to the section on painting recommendations for mineral fiber products.

Field Tegularization of Fiberglass Products
Field fabrication of reveal edges on a Painted Nubby or Optima Open Plan fiberglass ceiling panel is accomplished in the same manner as a reveal edge would be cut on a mineral fiber panel. When the field cut will be exposed after installation, the edge can be treated using a white, latex base, tub and tile caulk. Lay a 1/4" bead of caulk in the reveal joint. Then tool the caulk with a wet wood stick such as a tongue depressor. Allow the caulk to set up prior to installation to protect against smearing. Drywall joint compound can also be used to fill the cut edge.

Repair of Vinyl Facing
A tear in the vinyl facing can be covered and resealed utilizing a white, latex base, tub and tile caulk (such as Dap or Red Devil). Place a bead of caulk in the opening caused by the tear, tool with a wood stick, and allow to dry prior to installing in the ceiling.

Back to FAQs