Six plates. Not six jobs.

These are unit types — the shapes a pre-war Chicago facade is actually made of. Each one carries the section it was measured from, the glaze as it weathered, why a unit like it comes off a building, and which of the four repairs it usually takes. One of the six takes none.

The sections and glazes are renderings generated from the specimen records below them, not photographs. Every number the drawings are built from is printed beside them, so you can check one against the other.

Cornice modillion

The projecting brackets under a cornice, at the top of the wall.

Measured section, drawn from the offsets in the table below.

WTW ochre 4, matt finish.

Measured section

Offsets for specimen 01, in inches from the wall face and above the bed joint
#	Out	Up
01	0.00″	0.00″
02	9.50″	0.00″
03	9.50″	2.25″
04	7.75″	3.50″
05	7.00″	6.25″
06	8.50″	8.00″
07	8.50″	10.50″
08	0.00″	10.50″

Face length: 11″
Bed depth: 9.5″
Height: 10.5″
Dry weight: 74 lb
Glaze: WTW ochre 4 · Matt
Colour: Warm buff, faintly green in the hollows

What the weather did

Soot held in the undercut and washed clean on the top surface, so the same unit is two colours depending on where you stand.

Why it came off

Water standing on the top surface, then a freeze. The bracket cracked along the bed joint and the front half moved forward about half an inch.

Route — Replacement in kind

A modillion is all profile. Once the front has moved there is nothing left to patch to, and a flat substitute reads as a mistake from the pavement.

Window surround, sill block

The sloped block under a window opening.

Measured section, drawn from the offsets in the table below.

WTW ochre 4, semi-gloss finish.

Measured section

Offsets for specimen 02, in inches from the wall face and above the bed joint
#	Out	Up
01	0.00″	0.00″
02	7.25″	0.00″
03	7.25″	1.50″
04	6.50″	2.00″
05	1.25″	4.75″
06	0.00″	4.75″

Face length: 24″
Bed depth: 7.25″
Height: 4.75″
Dry weight: 46 lb
Glaze: WTW ochre 4 · Semi-gloss
Colour: Warm buff, a half step lighter than the modillion

What the weather did

The wash surface has lost most of its gloss; the return under the drip is almost as fired.

Why it came off

The drip under the nose had been filled with sealant at some point, so water ran back along the underside and into the joint instead of falling clear.

Route — Replacement in kind

The slope and the drip are the whole function of the unit. Patching the nose gives back the shape without giving back the drip, and the water finds the same path again.

Cartouche

The ornamental panel over an entrance or at a parapet centre.

Measured section, drawn from the offsets in the table below.

WTW cream 2, slip finish.

Measured section

Offsets for specimen 03, in inches from the wall face and above the bed joint
#	Out	Up
01	0.00″	0.00″
02	4.50″	0.00″
03	5.25″	1.75″
04	6.00″	5.50″
05	5.00″	9.25″
06	3.25″	12.00″
07	0.00″	12.00″

Face length: 19″
Bed depth: 6″
Height: 12″
Dry weight: 61 lb
Glaze: WTW cream 2 · Slip
Colour: Pale cream, slightly chalky

What the weather did

Crazing across the whole face, tight and even. It is not a defect and it does not need repair — it is what a slip glaze does after eighty winters.

Why it came off

Not a failure. This one came down with a parapet rebuild and is on the shelf as a moulding reference.

Route — Leave it and monitor

The single most common thing we are asked to replace, and the single most common thing that does not need replacing. Crazing is not cracking.

Belt-course block

The continuous horizontal band that divides one storey from the next.

Measured section, drawn from the offsets in the table below.

WTW grey 1, matt finish.

Measured section

Offsets for specimen 04, in inches from the wall face and above the bed joint
#	Out	Up
01	0.00″	0.00″
02	5.75″	0.00″
03	5.75″	1.25″
04	4.25″	2.50″
05	4.25″	5.00″
06	0.00″	5.00″

Face length: 18″
Bed depth: 5.75″
Height: 5″
Dry weight: 38 lb
Glaze: WTW grey 1 · Matt
Colour: Cool mid grey with a brown undertone

What the weather did

Even, and the easiest of the six to match — a matt grey has nowhere to hide but also nothing much to imitate.

Why it came off

The steel shelf angle behind it corroded and expanded. The block did not fail; it was pushed.

Route — Replacement in kind

The unit is the symptom. Replacing it without getting to the angle behind means doing it again in nine years, and we say so in writing before quoting.

Pier capital

The top of a masonry pier, usually at street level.

Measured section, drawn from the offsets in the table below.

WTW ochre 4, semi-gloss finish.

Measured section

Offsets for specimen 05, in inches from the wall face and above the bed joint
#	Out	Up
01	0.00″	0.00″
02	8.00″	0.00″
03	8.00″	3.00″
04	10.25″	5.50″
05	10.25″	7.25″
06	9.00″	8.50″
07	0.00″	8.50″

Face length: 22″
Bed depth: 10.25″
Height: 8.5″
Dry weight: 96 lb
Glaze: WTW ochre 4 · Semi-gloss
Colour: Warm buff

What the weather did

At street level, so it has been washed, salted and leaned on. The lower two inches have lost glaze entirely.

Why it came off

Spalling on the exposed face, roughly a fifth of the area, with the glaze still sound around it and no crack through the body.

Route — Patch repair

This is what a patch is for. The body is sound, the profile survives, and a fired replacement of a ninety-six pound unit at street level is a great deal of money for a repair a good patch will outlive.

Balustrade baluster

The turned uprights in a parapet or balcony rail.

Measured section, drawn from the offsets in the table below.

WTW cream 2, slip finish.

Measured section

Offsets for specimen 06, in inches from the wall face and above the bed joint
#	Out	Up
01	0.00″	0.00″
02	4.00″	0.00″
03	4.00″	1.50″
04	2.25″	3.25″
05	1.75″	8.00″
06	3.50″	12.50″
07	3.50″	15.00″
08	0.00″	15.00″

Face length: 8″
Bed depth: 8″
Height: 15″
Dry weight: 43 lb
Glaze: WTW cream 2 · Slip
Colour: Pale cream

What the weather did

Weathered on one side only. A balustrade faces the weather and the roof at once, and matching means matching both faces of the same unit.

Why it came off

Two of nineteen were missing entirely and four were cracked through the waist. The rail had been rebuilt at least once already.

Route — Cast stone or GFRC

Above the sightline, not a landmark elevation, and nineteen units. Cast stone at the four cracked positions costs a third of fired replacements and no one on the pavement will ever know.

3 of the 6 take replacement in kind. The rest take a patch, a substitute, or nothing at all — and a quote that proposes fired replacements for all six is not a quote, it is a catalogue order.