Fibre Reinforced Facade Encyclopedia: Materials
FRP versus GRC is the choice between a polymer composite and a cement composite for a moulded facade. Fibre reinforced polymer is glass fibre in a cured thermoset resin; glass fibre reinforced concrete, called GFRC in North America, is alkali resistant glass fibre in a cement matrix. They compete for the same work, which is facade geometry too complex for precast or metal, and they separate on one decisive property: GRC can be non-combustible and FRP cannot.
Take the fire question first. If the project needs a Deemed-to-Satisfy non-combustible external wall, GRC is the answer and the rest of this page is academic. If a Performance Solution is available, the comparison is open.
At a glance
| Property | Typical value | Note |
|---|---|---|
| Weight | FRP 5 to 32 kg/m²; GRC 30 to 50 kg/m² | FRP is roughly a third to a half of GRC |
| Combustibility | FRP cannot be non-combustible; GRC can | GRC via AS 1530.1; FRP via AS 5113 full-scale test |
| Flexural strength | FRP 150 to 250 MPa; GRC 20 to 30 MPa sprayed | Different scales; compare with stiffness and weight |
| Elastic modulus | FRP 10 to 25 GPa; GRC 10 to 20 GPa | Both deflection governed in thin sections |
| Skin thickness | FRP 3 to 8 mm; GRC 10 to 20 mm | |
| Max single element | FRP up to 2.4 by 10 m; GRC about 3 by 6 m | ShapeShell-RT published size for FRP |
| Thermal expansion | FRP 15 to 30 x 10⁻⁶/°C; GRC 10 to 20 x 10⁻⁶/°C | FRP needs wider joints or sliding fixings |
| Thermal conductivity | FRP 0.29 to 0.72 W/m·K; GRC about 0.39 W/m·K | ShapeShell values; GRC also brings thermal mass |
| Cost per square metre | GRC lower at simple repetitive geometry | FRP competitive as geometry and unit size grow |
| Surface | FRP gel coat or PVDF; GRC integral, off-form or etched | GRC finish is in the material, FRP finish is on it |
Where GRC wins
Non-combustibility is the first and largest. GRC has no polymer matrix, so a product can be tested to AS 1530.1 and classified Not Deemed Combustible, which satisfies the NCC external wall requirements for Type A and Type B construction through the Deemed-to-Satisfy route, with no fire engineer and no building-specific assessment. ShapeShell-RC holds that result from Ignis Labs. The international equivalents are EN ISO 1182 for Class A1 or A2 and ASTM E136. On a large number of Australian projects this single property ends the comparison before it starts, and any FRP supplier who tells you otherwise is wrong.
Thermal mass is the second. A cement panel stores and releases heat; a 4 mm polymer skin does not. Where the facade is intended to contribute to internal temperature stability, or where a Section J calculation is relying on the wall’s heat capacity, GRC contributes and FRP does not.
Cost per square metre at simple geometry is the third. On flat or singly curved repeating panels the raw materials are cheap, the process is fast and the mould is straightforward. FRP at that geometry pays for resin and hand labour to deliver a panel a cement composite could produce for less. GRC also has the more mature specification landscape: GRCA grades, BS EN 1169 and 1170 factory production control, and batch MOR and LOP testing a specifier can write into a worksection and audit.
Fourth, GRC is more dimensionally stable under temperature, it is not UV sensitive so the surface system is optional rather than essential, and it takes the full range of concrete finishes straight from the mould face.
Where FRP wins
Weight is the clearest. At 5 to 32 kg per square metre against 30 to 50, an FRP facade is a third to a half the mass of GRC and around a tenth of precast. That matters on recladding, on cantilevered and projecting elements, on tall buildings where facade dead load accumulates through the frame, and on any element installed by hand or from rope access rather than by crane.
Complex geometry is the second. FRP takes shape from a laminating mould and can hold double curvature, deep undercuts, sharp arrises and continuously varying sections that a sprayed cement skin cannot reliably fill or release. Where every panel on a facade is different, FRP tooling is cheaper to modify and faster to turn around.
Unit size is the third and follows from the first two. ShapeShell-RT is produced as single elements up to 2.4 by 10 metres. A GRC panel that size needs a substantial stud frame and sits at the limit of standard transport and craneage. Larger units mean fewer joints, fewer fixings and a cleaner elevation.
Fixing economy is the fourth. A lighter panel needs fewer and smaller anchors, lighter substructure, a smaller crane and fewer people on the lift. Where installed cost is dominated by access and craneage rather than by the panel, FRP can be cheaper delivered and fixed even when it is dearer per square metre ex-works.
Fifth, FRP is tougher in handling. It does not chip at arrises the way a thin cement skin does, which reduces transport breakage and damage at ground level.
The fire comparison, stated plainly
FRP is a polymer composite. It has a resin matrix that burns, and it cannot pass AS 1530.1, EN ISO 1182 or ASTM E136. Any claim that an FRP product is non-combustible is false and should be met by asking for the furnace test report, which will not exist.
What a good FRP system has instead is a reaction-to-fire and full-scale-test pathway. ShapeShell-RT holds an AS 5637 Group 1 classification from AWTA Product Testing and an EN 13501-1 classification of B-s2, and has passed the full-scale BS 8414 and AS 5113 facade test at BRE Global, meeting all AS 5113 criteria. That evidence supports a Performance Solution under the NCC verification route, assessed by a fire engineer for the specific building, with its sprinklers, cavity barriers and evacuation strategy taken into account. It is a legitimate compliance pathway and it is used on real buildings. It is not the same thing as non-combustibility, it costs more in consultant time, and it can be refused by a certifier, a client’s insurer or a project’s own fire brief.
Choosing in practice
Run the constraints in order. Is a non-combustible external wall required by the NCC construction type, by the client or by the insurer? If yes, specify GRC. If no, what is the structure’s dead load allowance for the facade, and does GRC at 30 to 50 kg per square metre fit inside it? If it does not, specify FRP. If both are open, the geometry decides: repeating and simple favours GRC on cost, non-repeating and double-curved favours FRP on tooling and unit size.
Mixed facades are common and legitimate: GRC on the compliant external wall envelope, FRP on sculptural elements, canopies and soffits where the fire provisions differ or weight binds. The two can share geometry and be matched closely enough in colour and texture that the transition is not read from the street, though a mock-up should confirm that before it is relied on.
Standards and references
- AS 1530.1 combustibility; AS 5113 full-scale facade test; AS 5637.1 group number
- NCC 2022 Volume One, Specification 7 and C2D10; Performance Solution and verification pathways (check the edition adopted in your jurisdiction)
- EN 13501-1 reaction to fire; EN ISO 1182; BS 8414 with BR 135
- GRCA Specification for the Manufacture, Curing and Testing of GRC Products; BS EN 1169 and BS EN 1170 parts 1 to 8
- ASTM D790 and ISO 14125 (FRP flexure); ASTM C947 and BS EN 1170-5 (GRC flexure)
- AS/NZS 1170.2 wind actions; AS 4284 facade testing
Related terms
Questions specifiers ask
Is FRP or GRC better for a facade?
Neither in the abstract. GRC wins where the external wall must be non-combustible, where thermal mass matters and where the geometry is simple and repetitive, because it is cheaper per square metre. FRP wins where weight is limited, the geometry is complex, the units are large or the installed cost is dominated by craneage and access.
Can FRP be non-combustible?
No. FRP has a polymer resin matrix and cannot pass AS 1530.1, EN ISO 1182 or ASTM E136. It is classified by reaction-to-fire tests and full-scale facade tests such as AS 5113 and BS 8414, and used on Type A and B buildings only as a Performance Solution.
How much lighter is FRP than GRC?
Roughly a third to a half the weight. FRP facade panels run 5 to 32 kg per square metre against 30 to 50 for GRC including ribs or frame. Against 150 mm precast at about 360 kg per square metre, FRP is around a tenth.
Which is cheaper, FRP or GRC?
GRC is usually cheaper per square metre on simple repetitive panels. FRP closes the gap and often wins on total installed cost where the geometry is complex, the panels are large, or lifting and access costs dominate, because lighter panels need smaller cranes, fewer fixings and fewer lifts.
Is GRC stronger than FRP?
In flexure, no. FRP reaches 150 to 250 MPa against 20 to 30 MPa for sprayed GRC. That comparison is only useful alongside density and stiffness, since both materials are designed to deflection limits in thin sections rather than to strength.
Can FRP and GRC be used on the same building?
Yes, and it is common. GRC is used where the external wall must be non-combustible and FRP on sculptural elements, soffits and areas where weight or geometry rules GRC out. Confirm the colour and texture match on a site mock-up before committing.
ShapeShift makes both. ShapeShell-RC is our GRC system with an AS/NZS 1530.1 Not Deemed Combustible result from Ignis Labs; ShapeShell-RT is our FRP system with a full-scale AS 5113 pass at BRE Global. See ShapeShell fire test data
Reviewed by Richard Halvorsen, General Manager, ShapeShift Technologies. Last updated September 2026.