Fibre Reinforced Facade Encyclopedia: Materials
Fibre reinforced polymer is a composite material made of reinforcing fibres, most often glass, held in a cured thermoset resin such as polyester, vinyl ester, epoxy or phenolic. In architecture it is laminated into thin, stiff, lightweight panels for facades, sculptural elements and interiors. The same material is called GFRP when the fibre is glass, and fibreglass in everyday use.
A ShapeShell-RT single-skin FRP facade panel of 3 to 8 mm weighs 5 to 32 kg per square metre and can be produced as a single element up to 2.4 by 10 metres.
At a glance
| Property | Typical value | Note |
|---|---|---|
| Density | 1,600 to 1,900 kg/m³ | Glass fibre and polyester or vinyl ester laminate |
| Panel thickness | 3 to 8 mm single skin; 10 to 50 mm monocoque | ShapeShell-RT published range |
| Weight in service | 5 to 32 kg/m² | ShapeShell-RT published range |
| Tensile strength | 100 to 300 MPa | ShapeShell-RT: 172 to 269 MPa |
| Flexural strength | 150 to 250 MPa | ShapeShell-RT: 221 to 241 MPa |
| Elastic modulus | 10 to 25 GPa | Lower than steel or concrete; deflection governs |
| Thermal expansion | 15 to 30 x 10⁻⁶ per °C | Higher than concrete; joint design matters |
| Thermal conductivity | 0.3 to 0.7 W/m·K | ShapeShell-RT published value 0.29 to 0.72 |
| Fire | Resin dependent; classified by reaction-to-fire tests | ShapeShell-RT: EN 13501-1 B-s2,d0; AS 5637 Group 1; AS 5113 full-scale pass |
| Service life | 50+ years with a suitable surface | Gel coat or PVDF protects against UV |
What makes FRP different
FRP separates strength from weight in a way no cementitious or metallic cladding can. The fibres carry the load and the resin holds them in position and protects them, so a laminate a few millimetres thick has the tensile strength of mild steel at a quarter of the density. That is why FRP is the material for long, unsupported spans, deep double-curved geometry, and any element that has to be lifted by hand or on a small crane.
The limitation is stiffness. FRP has a low elastic modulus, so panels are designed to a deflection limit rather than a strength limit, and large panels gain stiffness from shape (monocoque shells, returns and ribs) or from a foam or honeycomb core in a sandwich construction.
Fibres and resins
Glass is the reinforcement for almost all architectural FRP. E glass is the standard; ECR glass adds corrosion resistance. Carbon fibre is used where deflection limits cannot otherwise be met, and aramid where impact or ballistic performance is required.
The resin sets the environmental and fire behaviour. Polyester is the lowest cost and adequate for most work. Vinyl ester improves chemical and fatigue resistance. Epoxy gives the highest strength but needs UV protection. Phenolic resins are chosen where flame spread and smoke must be as low as a polymer composite can achieve. Fire retardant additives and intumescent gel coats improve reaction-to-fire results in all systems.
How it is made
Hand lay-up places layers of glass mat or fabric into an open mould and wets them with resin; it is flexible and suits one-off geometry. Vacuum infusion draws resin through dry fibre under vacuum for a denser and more consistent laminate. Resin transfer moulding and pultrusion are used for repeat components and profiles. In all cases the mould defines the surface, so a gel coat or a moulded-in texture becomes the visible face of the panel, and CNC-cut tooling makes complex geometry economical.
Where it is used
- Facade panels where weight, span or curvature rule out GRC or precast
- Sculptural and public art elements exposed to weather
- Recladding of existing buildings with limited structural capacity
- Interior feature walls and ceilings
- Civil elements: tunnel linings, station canopies, noise walls, stay-in-place formwork
Fire performance, stated precisely
FRP is a polymer composite, so it is classified by reaction-to-fire tests rather than as non-combustible. The results that matter for external walls are the EN 13501-1 class (Class B is the best a polymer composite normally reaches), the AS 5637 group number for internal linings, the ASTM E84 flame spread index in the US, and above all the full-scale facade test: AS 5113 in Australia, BS 8414 with BR 135 in the UK, NFPA 285 in the US.
In Australia, an FRP facade on a Type A or B building is not a Deemed-to-Satisfy solution. It is delivered as a Performance Solution supported by an AS 5113 full-scale test and a fire engineer’s assessment of the specific building. ShapeShell-RT has passed the full-scale BS 8414 and AS 5113 test at BRE Global and carries an EN 13501-1 classification of B-s2,d0, which is the evidence a fire engineer uses for that pathway.
Standards and references
- ASTM D790 and ISO 14125 (flexural properties), ASTM D638 and ISO 527 (tensile), ASTM D256 (impact)
- EN 13501-1 (reaction to fire), AS 5637.1 (group number), ASTM E84 (flame spread)
- AS 5113, BS 8414 with BR 135, NFPA 285 (full-scale facade tests)
- IBC Section 2612 (2018) / 2613 (2021), Fiber-reinforced polymer
- NCC 2022 Volume One C1V3 (external wall verification method) (check the edition adopted in your jurisdiction)
- ISO 14692 and ACI 440 (structural FRP references)
Where this matters on a ShapeShift project
Spanda, Elizabeth Quay, Perth: A 29 metre sculptural work in FRP where weight, wind load and double-curved geometry made a polymer composite the only practical material.
Related terms
Questions specifiers ask
Is FRP the same as fibreglass?
In practice yes. Fibreglass is the everyday name for glass fibre reinforced polymer, which is the most common form of FRP. FRP is the broader term and also covers carbon and aramid fibre composites.
Is FRP non-combustible?
No. FRP has a polymer resin matrix, so it cannot pass a combustibility test. It is classified by reaction-to-fire tests and by full-scale facade tests. A good FRP facade product will hold an EN 13501-1 Class B, an AS 5637 Group 1 and a pass in a full-scale test such as AS 5113 or NFPA 285.
Can FRP be used on the external wall of a high-rise in Australia?
Only as a Performance Solution. The NCC requires external walls of Type A and B buildings to be non-combustible under the Deemed-to-Satisfy provisions. An FRP system can be accepted through Verification Method C1V3 using an AS 5113 full-scale test result together with a fire engineered assessment of the building, sprinklers and cavity barriers.
How much does an FRP facade panel weigh?
Between 5 and 32 kg per square metre depending on thickness and construction, roughly a tenth of precast concrete and a third to a half of GRC.
How long does FRP last outdoors?
With a gel coat or a PVDF paint system, 50 years or more. The resin itself is UV sensitive, so the surface system is part of the specification, not an optional extra.
What is the largest single FRP panel?
ShapeShell-RT panels are produced up to 2.4 by 10 metres as a single element. Larger elements are made as monocoque or sandwich construction and joined on site.
Designing something that will not work in concrete or metal? ShapeShell-RT is our FRP system with a full-scale AS 5113 facade test pass. See ShapeShell-RT specifications
Reviewed by Richard Halvorsen, General Manager, ShapeShift Technologies. Last updated September 2026.