Fibre Reinforced Facade Encyclopedia: Materials
Terracotta cladding is an external rainscreen made from extruded, fired clay elements hung on a metal rail system. The clay is extruded as a hollow, twin-wall section, cut to length, dried and fired, and the resulting tile is clipped or slid onto horizontal rails with open joints between elements. It comes in two main forms: flat panels or tiles for wall surfaces, and baguettes, which are solid or hollow rods used as sunshades, screens and fins.
Terracotta is a fired ceramic, so it is non-combustible and it never needs a coating to survive UV. It is also an extrusion, so every element has the same cross-section along its length.
At a glance
| Property | Typical value | Note |
|---|---|---|
| Material | Extruded and fired clay | Twin-wall hollow section with internal webs |
| Weight | 30 to 60 kg/m2 | Including the rail substructure at the upper end |
| Tile face thickness | 15 to 30 mm | Overall section depth typically 20 to 40 mm |
| Tile size | Up to about 1,200 to 1,800 mm long, 200 to 600 mm high | Length limited by firing and handling |
| Baguettes | 40 to 100 mm across, spans of 1.5 to 3 m | Round, square or elliptical section |
| Fire | Non-combustible where tested | Commonly A1 to EN 13501-1; ask for the AS 1530.1 report for Australia |
| Substructure | Aluminium vertical carriers with horizontal hook-on rails | Panels slide or clip on, often with a retaining clip |
| Joints | Open, 8 to 12 mm typical | Cavity visible; membrane behind must be UV stable and dark |
| Dimensional tolerance | Wider than metal or moulded panels | Firing shrinkage; typically in the order of 1 to 2 mm |
How it is made and how it is fixed
Clay is mixed to a stiff paste, forced through a die, and emerges as a continuous hollow section with internal webs that give it stiffness at low weight. It is cut to length, dried, and fired at high temperature. Surface treatment is applied before firing: natural clay body colour, an engobe, which is a clay slip that fires to a matt coloured surface, or a glaze for a glossy finish. The colour is in the ceramic, so it does not fade and it needs no recoating over the life of the facade.
Installation is a rainscreen system. Aluminium brackets fix to the structure, vertical carrier profiles span between them, and horizontal rails clip to the carriers at the tile module. Tiles are lowered or slid onto the rails from above or from the end and are held by the profile of the extrusion itself, often with a clip or grub screw to stop lift and rattle. Because each tile is independent, a damaged tile can be removed and replaced without disturbing its neighbours, which is one of the system’s real advantages on a building that will be hit by things at low level.
Weight, and what it means for the substructure
At 30 to 60 kg per square metre, terracotta is heavier than a metal rainscreen, roughly comparable to a glass fibre reinforced concrete (GRC, GFRC) panel, considerably heavier than a fibre reinforced polymer panel, and much lighter than precast concrete or dimension stone. It is a lightweight cladding in the sense that matters to a structural engineer, but it is not a light one.
The consequence is in the substructure rather than in the building frame. The rails and brackets have to carry that dead load plus wind pressure and suction, they have to be corrosion rated for the exposure, and on a recladding project the existing structure and its fixings have to be verified for the added mass. The brackets also bridge the insulation, so the thermal bridging assessment is done on the real bracket layout, not on a nominal one.
Fire performance
Fired clay contains no organic binder and no polymer, so terracotta tiles are a non-combustible material and are routinely classified A1 under EN 13501-1 without further testing in Europe. In Australia the test that matters for the Deemed-to-Satisfy route for external walls of Type A and Type B buildings is AS 1530.1, and a specific product needs a current report for the product being supplied. Ask for it rather than relying on the material category.
Where the geometry stops
Extrusion is what makes terracotta cheap, consistent and light, and it is also what limits it. An extruded section is constant along the extrusion axis. That gives a designer a genuinely useful palette, because the die can be cut to any profile: ribbed, fluted, angled, chamfered, rounded, deeply raked. Those profiles repeat perfectly across an entire elevation.
What it cannot do is vary. Terracotta cannot produce double curvature, a shape that changes across the element, a panel that tapers, a moulded relief, or a freeform surface. Corners need purpose-made L-shaped extrusions and those have limits on return depth. Non-rectangular elevations are handled by cutting tiles, which exposes the hollow core and needs an end cap or a return piece. Firing shrinkage also means tolerances are wider than for a metal or moulded panel, so joints have to absorb more variation.
- Constant cross-section only; no variation along the element
- No double curvature and no freeform surfaces
- Corners and reveals need special extrusions with limited return depth
- Cut ends expose the hollow section and need capping
- Colour range limited to what the clay body, engobes and glazes give
- Larger tiles are constrained by firing and by breakage in handling
This is the practical dividing line between terracotta and a moulded panel. Where the elevation is a rhythm of flat or profiled rectangles, terracotta is a strong, durable, non-combustible and well proven choice. Where the elevation is three-dimensional, curved, tapered or varies panel to panel, it is the wrong technology and a cast or moulded system is the alternative.
Standards and references
- EN 1304 and EN 14411 for fired clay products; EN 539 for water absorption and frost resistance
- EN 13501-1 reaction to fire classification (fired clay is commonly Class A1)
- AS 1530.1 combustibility; NCC 2022 Volume One external wall provisions (check the edition adopted in your jurisdiction)
- AS 4284 Testing of building facades; AS/NZS 1170.2 wind actions
- CWCT Standard for Systemised Building Envelopes (United Kingdom rainscreen guidance)
- AS 4312 atmospheric corrosivity zones, for specifying the aluminium and stainless steel substructure
Related terms
Questions specifiers ask
How much does terracotta cladding weigh?
Typically 30 to 60 kg per square metre including the rail substructure. That is comparable to a GFRC panel, heavier than a metal or FRP rainscreen, and far lighter than precast concrete or stone.
Is terracotta cladding non-combustible?
Fired clay contains no organic binder, and terracotta products are routinely classified A1 to EN 13501-1. For an Australian project, ask for a current AS 1530.1 report for the specific product. The rest of the wall build-up is assessed separately.
How is terracotta cladding fixed?
As a rainscreen. Aluminium brackets and vertical carriers support horizontal rails, and the tiles clip or slide onto the rails with open joints between them. Individual tiles can be removed and replaced.
Can terracotta be curved?
Only in the plane of the extrusion die. An extruded section has a constant cross-section along its length, so double curvature, tapering and freeform surfaces are not possible. Curved elevations are approximated by faceting.
Terracotta works where the elevation is a rhythm of rectangles. Where the geometry is three-dimensional and still has to be non-combustible, ShapeShell-RC is a moulded GFRC system tested Not Deemed Combustible to AS/NZS 1530.1 by Ignis Labs. Compare ShapeShell-RC
Reviewed by Richard Halvorsen, General Manager, ShapeShift Technologies. Last updated September 2026.