Decorative Stucco Trims, Bands and Cornices in the GTA: What They Cost and Why They Fail

Banding, or a band course, is a horizontal projecting strip running across an elevation, usually at a floor line or between storeys. It is the workhorse of stucco trim and often the only trim a house needs.

A cornice is the profile at the top of the wall where it meets the roof or the soffit. It is usually the largest and most sculptural profile on the building, and on the rear elevation shown above it is the element that gives the wall its scale.

Window and door surrounds are the profiles framing an opening. They can be a simple flat casing, a keystone at the head, or a full architrave. A header or lintel detail is the piece across the top of the opening specifically.

Sills are the projecting shelf under a window. They are the single most important trim to detail correctly because they are directly above a large area of wall and directly below a window, which is where leaks originate.

Quoins are the stacked corner blocks at the outside corners of a building. They read as traditional and they are heavy visually, so they need the rest of the elevation to support them.

A reveal is the opposite of a trim: a recessed groove cut into the wall rather than a projection added to it. Reveals are the go-to move on contemporary elevations because they give you a line without giving you a horizontal surface to collect water.

Water sitting on a horizontal surface. That is it. That is the whole failure mode.

Every projecting trim has a top face. If that face is flat, or worse if it slopes back toward the wall, water sits on it. It sits there through rain, it sits there as snow, it freezes and thaws, it works into any tiny crack in the finish, and it gets behind the trim and into the wall.

The correct detail is positive slope on every top surface, meaning the top face pitches away from the building so water runs off. On a well-built band or sill you can see this: put a level on it and the outside edge is lower than the inside edge.

Second, the finish has to be carried fully over the top face, over the outside edge, and returned underneath. A trim finished only on the visible front face will let water into the foam core at the top edge, and once water is in the core, freeze-thaw destroys the profile from the inside.

Third, a drip edge on the underside of the outside edge. A small groove or a shaped kerf on the underside stops water running back along the bottom of the trim and down the wall face. Without it you get the dirty vertical streaks below sills that you see on so many buildings.

Fourth, mesh reinforcement fully around the profile, not just on the wall around it. The corners and edges of a shaped trim are the highest stress points on the whole elevation and they need reinforcement, particularly at the outside arris where impact and thermal movement concentrate.

And fifth, on longer runs, joints. A band running forty feet without a joint will crack. It needs breaks that allow for thermal movement, placed where they will not be visually obvious.

Unlike wall area, trim is priced by the running foot and by the complexity of the profile.

For planning in the GTA: simple bands and window surrounds generally run around $18 to $45 per linear foot. Custom sills, cornices, quoins and feature profiles typically run $45 to $120 and up per linear foot, because they involve larger foam sections, more shaping, more mesh, and considerably more labour on the wall. A front elevation trim package commonly plans between $3,500 and $18,000 and up depending on how much of the vocabulary you use.

The practical implication is that trim cost scales with how many running feet you specify, not with how big your house is. A band around all four elevations of a large home is a lot of linear footage. A band on the front only is a fraction of it, and on many houses nobody ever sees the difference.

The most cost-effective moves, in my experience: a single band on the visible elevations, simple surrounds on the front windows only, and reveals everywhere else. Reveals are the best value in the whole catalogue because they are cut into the wall you are already building, so the marginal cost is small.

The least cost-effective: quoins on every corner of a large house. They are a lot of linear footage in a complex profile, and they only work on the right architecture.

Most of our trim work is not new. It is repairing and recoating trim that is twenty years old and starting to show.

The usual findings: the top face has flattened or sagged so water is now sitting on it, the outside arris is chipped from impact or from a ladder, the finish has worn thin on the top face where weather hits hardest, the joints have opened, or a section of the core is soft because water got in years ago.

Repair means cutting back to sound material, rebuilding the profile with new foam or base coat build-up, re-establishing the slope, re-meshing including around the edges, and refinishing. On a cornice at roof level the access is the significant cost, not the repair itself.

When we are recoating an elevation anyway, bringing the trims into the same scope is almost always the right call, and it is where cheap quotes hide. A recoat that does the field of the wall and leaves twenty-year-old trim in original condition will look wrong, because the new field finish will make the tired trim obvious. Ask specifically whether the trims, sills and cornices are included and how the top surfaces are being handled.