Curved elevations can be clad with terracotta in two distinct ways: straight units can approximate the arc as a series of short chords, or specially formed curved units can follow the geometry more closely. LOPO’s 2017 archive introduced a curved hollow profile intended for round wall surfaces. The concept remains useful, but radius, section, span, fixing and current production capability must be reviewed for the actual project.
Faceted panels and curved profiles create different results
A large-radius wall can often be divided into flat modules. Each panel or louver stays straight, while small changes at the joints build the overall curve. From a distance the elevation may read as smooth; at close range, the facets and joint angles remain visible. Shorter modules produce a closer approximation but increase the number of joints and supports.
A purpose-made curved profile offers another visual language. Its face and hollow section are formed to a defined radius, allowing a more continuous sweep across a bay. This may reduce the faceted appearance, but it introduces tooling, tolerance, orientation, packaging and replacement considerations that do not apply in the same way to standard straight units.
| Approach | Potential advantage | Points to resolve |
|---|---|---|
| Straight units on an arc | Uses standard profiles and adjusts the curve through module and joint angles | Visible faceting, more joints, bracket rotation and edge clearances |
| Purpose-made curved units | Can follow the design radius more continuously | Tooling, radius tolerance, sectional strength, handed pieces and replacement strategy |
Read the archived radius guidance as a starting point
The original article suggested that flat terracotta panels could form arcs with a radius greater than about 3 m by adjusting the angle between adjacent units, with either horizontal or vertical installation possible. It also described vertical fixing for tighter curves below 3 m. That is historical project guidance, not a universal engineering limit.
The practical module depends on the radius, included angle, chord length, panel depth, joint width and viewing distance. A deep louver may clash at its inner edges even when a thin flat panel appears to fit. The facade designer should model the real section and bracket, then confirm the geometry with the manufacturer and structural engineer.
The curved louver concept
The archived LOPO development is shown as a hollow extruded piece with a curved face and internal webs. Several units can be repeated around a rounded wall. Depending on the project, a profile of this type may act as a visual louver, sunscreen, screen element or feature cladding component; those names do not by themselves define its structural role or performance.
Before using the concept, confirm whether the current production line can make the required radius, cross-section, length, colour and finish. Some curves may need a dedicated die or minimum production quantity. The design should also distinguish concave from convex pieces and record the installation orientation so the correct profiles arrive in the correct sequence.
Coordinate geometry, joints and visual rhythm
Design radius
State whether the radius is measured to the substrate, support rail, profile centreline or visible face. A small reference error can accumulate around the arc.
Module and spacing
Set out the number of units, clear gaps and end conditions. Equal spacing may need adjustment near entrances, corners or transitions to flat walls.
Colour and surface
Approve representative fired-clay samples and decide how tonal variation should be blended. Curved faces can reflect light differently across the same colour.
Access and replacement
Plan how individual units can be installed, inspected and replaced without dismantling an impractically large part of the screen.
A three-dimensional elevation model is particularly valuable for arcs. It can identify clashes, irregular end gaps and bracket rotations before fabrication. A full-scale segment mock-up then confirms whether the curve reads as intended from normal approach routes and viewing distances.
Fixing and performance belong to the complete system
Terracotta profiles should be assessed with their supports, anchors, rails and building structure. Wind actions, dead load, seismic movement where relevant, impact risk, thermal movement and differential tolerances all affect the detail. Long or deep profiles may need internal reinforcement or intermediate support, subject to engineering review and current product testing.
If the elements are intended as solar shading, calculate their orientation, spacing and depth for the facade direction and local sun path. Do not assume that the word “louver” proves a particular glare, heat-gain or ventilation result. Fire performance, weathering and maintenance also require evidence appropriate to the product and local code.
From an arc elevation to a sample assembly
- Provide plan geometry, radii, elevations, sections and intended profile orientation.
- Confirm straight versus curved units, available sections, lengths, finishes and quantities.
- Coordinate the support system, joints, ends, corners and movement allowances.
- Review physical colour samples and a full-scale curved mock-up segment.
- Approve numbering, packing, installation sequence and spare-unit requirements.
Explore standard terracotta baguettes and louvers, compare terracotta rainscreen options, and review completed work in the project gallery.