A GFRC panel is a thin cementitious skin, typically 10 to 25 mm thick, either fixed directly to a supporting structure or bonded with flex anchors to a steel stud frame that carries it. Everything a specifier needs to settle before writing the section follows from that: how thick the skin is, how big a single panel can be, how it is held, how the joints move, and which of those choices actually drives the price.
GFRC is glass fibre reinforced concrete, called GRC in Australia and the United Kingdom. This guide uses both terms and gives dimensions in metric with imperial equivalents, because the two markets specify the material differently and the difference matters. For the choice between GFRC and conventional precast, see GRC vs precast concrete panels.
GFRC panel thickness
There is no single standard thickness, and the number depends on which system is being specified.
| System | Skin thickness | Notes |
|---|---|---|
| Sprayed GFRC skin, general | 10 to 15 mm, around 0.4 to 0.6 in | Built up in layers, compacted between passes |
| ShapeShell-RC | 15 to 25 mm, around 0.6 to 1.0 in | Sprayed and laid into moulds matched to the approved shop drawings |
| Large format European panel systems | From around 13 mm, 0.5 in | Published performance comparable to UHPC at that thickness |
| North American stud frame systems | 19 to 25 mm, 0.75 to 1.0 in | Skin bonded by flex anchors to a steel stud or HSS frame |
The reason to care is that thickness is not a proxy for strength in this material. A thin sprayed skin gets its flexural capacity from fibre content and fibre orientation, not from section depth. Asking a supplier for a thicker panel usually adds weight without adding useful capacity, and it is the wrong lever if the real problem is span or fixing.
Panel sizes, and what actually limits them
Published typical sizes for North American stud frame GFRC systems run to around 4.6 by 9.1 m, 15 by 30 ft, with some systems going to about 10.7 m, 35 ft, in one direction. European large format panel systems market panel sizes big enough that the facade does not need to be interrupted for the material’s sake.
In practice the panel size on a given project is set by the first of these to bind:
- Mould and plant. The mould has to be built, filled and demoulded, and the panel has to come out of the factory.
- Transport. Road width and container dimensions cap a single piece long before the material does. This is where GFRC’s low weight pays, because the limit becomes volume rather than mass.
- Handling and install. A panel must be liftable and positionable with the plant available on site, which on a constrained site is often smaller than the factory could justify.
- Movement. A larger panel accumulates more thermal and moisture movement across its length, which the joint design has to absorb.
- Fixing geometry. The fixing system has to reach back to a supporting element, so grid and panel size are one decision, not two.
Returns matter as much as face dimensions and get missed in specifications. North American systems publish integral returns of around 200 mm, 8 in, with deeper returns achievable as part of a framed assembly. If the design has a deep reveal, the return depth belongs in the specification alongside the panel size.
Weight
Two numbers get confused here. The GFRC skin on its own is light: a 15 mm cementitious skin is a small fraction of the mass of a 100 mm reinforced precast panel of comparable span. A complete framed system is heavier, because the steel frame, anchors and any backing are part of it. North American manufacturers publish typical system weights around 88 to 98 kg per square metre, 18 to 20 lb per square foot, for stud frame GFRC assemblies. ShapeShift rates ShapeShell-RC at around 50 per cent lighter than precast concrete.
When comparing quotes, confirm whether the figure quoted is the skin or the assembled system. It is the single most common apples-to-oranges comparison in facade tendering.
Fixing systems
There are three approaches, and they are not interchangeable.
Stud frame with flex anchors. The GFRC skin is connected to a steel stud or hollow section frame by flexible pins, commonly L or T shaped and galvanised, which allow the skin to move relative to the frame without cracking. The frame carries the load to the structure. This is the North American norm and it produces a panelised system with a published baseline depth of around 175 mm, 7 in, or more.
Direct fix to a backing structure. Panels are fixed back to a structural wall, slab edge or subframe with brackets, either face-fixed or with concealed fixings. Simpler and shallower, and the usual approach where a substrate already exists.
Rail or cassette systems. Panels are hung on horizontal or vertical rails, which speeds install and simplifies replacement of a single panel later.
Three things to specify regardless of approach: whether fixings are concealed or expressed, who engineers the support framing, and whether a single panel can be removed and replaced without disturbing its neighbours. The last one is cheap to design in and expensive to retrofit.
Joints and movement
GFRC moves with temperature and with moisture. Joint width, sealant selection and the movement allowance at each panel edge are where thin-section facades succeed or fail, more than panel design is. Get the movement calculation from the supplier at design stage rather than accepting a nominal 10 mm joint because it looks right on the elevation.
What drives the cost of a GFRC package
A rate per square metre for GFRC is close to meaningless, because the same material varies by a multiple depending on how the job is drawn. In the order that usually matters:
- Number of unique panel types. Moulds are the capital cost. Twenty panels off one mould is a completely different job from twenty panels off twenty moulds at the same area.
- Geometry. Flat and single curvature are inexpensive. Double curvature, deep relief and perforation add mould complexity, spraying time and handling.
- Finish. Through-pigmented colour off a standard mould is the base. Coatings, polishing, acid wash, sandblast and bonded stone each add a process.
- System type. A framed stud system carries steel, anchors and fabrication that a direct-fixed panel does not.
- Tolerance and fixing. Tight tolerances and concealed fixings add engineering and install time.
- Programme. Compressing delivery means building more moulds to hold the production rate, which is a direct cost rather than a scheduling adjustment.
The largest lever is the first one and it is only available early in design. Rationalising an elevation from thirty panel types to eight, without changing how the building reads, is the most effective cost reduction available in a GFRC package.
Fire and compliance
GFRC is cement based with no polymer core, which is why it survived the cladding reckoning that removed combustible composite panels from the market. In Australia it is classified non-combustible when tested to AS 1530.1. European systems commonly publish a Class A1 reaction-to-fire classification.
Two things hold in every market. Compliance is assessed on the complete wall assembly, not on the panel: backing wall, supports, insulation, cavity treatment, fixings, sealants and coatings all form part of it. And the evidence that counts is the test report matched to the product supplied, not a claim in a brochure. ShapeShift publishes independently tested fire performance data on its material fire rating page.
Sustainability and service life
This is the part of the GFRC story that is under-argued, and it is mostly about mass. A thin-section panel uses a fraction of the cement of an equivalent precast element, and cement is where the embodied carbon in concrete sits. Lower mass then reduces the supporting steel, the transport movements and the lifting plant, so the saving compounds through the build rather than stopping at the panel.
On service life, North American manufacturers publish 60 years and more for framed GFRC systems. The mechanism behind that is the absence of steel reinforcement in the skin: with no bar to corrode there is no cover to carbonate through and no spalling at the cover zone, which is the failure mode that drives most precast facade remediation. What governs GFRC service life instead is the fibre specification, the coating where one is used, and the joint and fixing detail. ShapeShift’s approach to material efficiency is set out on its sustainability page.
What to put in the specification
- Material stated as GFRC or GRC, cement based, not interchangeable with GRG or FRP
- Fibre type, alkali-resistant glass with the zirconia content required by the nominated standard
- Skin thickness and whether the system is framed or direct-fixed
- Panel size limits, return depths and the panel type schedule
- Dimensional tolerance on size, bow and squareness
- Fixing system, concealed or expressed, and who engineers the support framing
- Structural criteria including wind actions and deflection limits for panel and framing
- Joint width, movement allowance and sealant specification
- Fire evidence: the test report for the product supplied plus system evidence for the nominated pathway
- Finish, colour reference, gloss level and the control sample approval process
- Quality system, mould replacement regime, and warranty on panel and coating
Project evidence
Thickness, fixing and tolerance are where panel specifications succeed or fail. These projects show each of them resolved.
- Wesley Place: panels at 15 to 25 mm with plus or minus 20 mm of adjustment engineered into the mounting system, which is how architectural tolerance is reconciled with structural tolerance.
- Jackson House: 1,388 square metres supplied with a purpose-designed rail and fixing system so installation needed minimal adjustment on site.
- 11 Eastern Road: every component 3D scanned against the architect’s model before delivery, which catches a deviation while it is still cheap to fix.
- Powerhouse Museum Parramatta: standard panel systems applied to an exoskeletal building, which is how a complex facade stays affordable.
Frequently asked questions
How thick is a GFRC panel?
Typically 10 to 25 mm, around 0.4 to 1.0 in, for the cementitious skin. ShapeShell-RC panels run 15 to 25 mm. North American stud frame systems commonly use a 19 to 25 mm skin, three quarters to one inch, bonded by flex anchors to a steel frame.
How large can a single GFRC panel be?
Published typical sizes for framed systems reach around 4.6 by 9.1 m, 15 by 30 ft, with some systems going to about 10.7 m in one direction. The binding limit on a real project is usually transport, site handling or movement across the panel length rather than the material.
How much does a GFRC panel weigh?
Check whether the figure is the skin or the system. North American manufacturers publish around 88 to 98 kg per square metre, 18 to 20 lb per square foot, for complete stud frame assemblies. The bare skin is far lighter, and ShapeShift rates ShapeShell-RC at about half the weight of precast concrete.
How are GFRC panels fixed?
Three ways: bonded with flexible galvanised pins to a steel stud or hollow section frame that carries the load, direct fixed with brackets to a backing structure, or hung on rails as a cassette. The choice affects system depth, install rate and whether one panel can be replaced on its own.
Is GFRC cheaper than precast?
Not reliably on panel rate, and often yes on installed cost, because a lighter facade reduces supporting steel, fixings, cranage and install time. Compare the assembled system on the actual elevation rather than the rate.
What is the difference between GFRC and UHPC?
Both use glass fibre reinforcement, but UHPC achieves a much denser matrix and is usually cast rather than sprayed. GFRC is the lighter, more formable and generally more economical of the two for facade cladding, which is why it dominates architectural panel work.
Getting numbers for a specific facade
Panel sizes, weights and tolerances are system-specific, so the useful next step on a live project is to send the elevations, the structural dead load allowance and the compliance pathway rather than to ask for a rate. Start at contact, see the product detail on ShapeShell-RC and standard GRC facade panels, or read the background in what is GRC.
Terms explained
Short definitions of the terms on this page, in our facade materials encyclopedia.
