A facade panel is only as reliable as the connection that holds it to the building. This guide explains the main ways lightweight FRP and GRC panels are attached, and how to choose between them.
The facade is the visible outer face of a building. The building envelope is the wider boundary between inside and outside, and it has to manage water, air, heat, sound, fire and movement. The attachment system is the physical link between the two: the panel on the outside and the structure behind.
Most FRP and GRC facades are rainscreens. The outer panels shed most of the rain, a drained and ventilated cavity removes the rest, and an inner barrier is the second line of defence. From outside to inside:
Self-weight acts straight down and is carried at a few fixed anchors.
Pressure pushes the panel in and suction pulls it out. Fixings resist both.
Heat and moisture make panels grow and shrink, so connections must flex.
Structures are often about 20 mm out either way. Adjustable fixings absorb it.
Choose a system to see its wall section, with the outside at the top. Each one holds the panel clear of the structure and keeps the cavity open.
Factory-applied undercoat sealer engineered to protect the substrate during transport and installation while providing an ideal bonding surface for field-applied topcoats. This option offers maximum flexibility for projects requiring on-site colour matching, intricate localized painting, or final site-applied architectural finishes.
Panels hang from horizontal rails on brackets, then are adjusted into line. It is quick to install and suits open-joint rainscreens.
Best for repeated panels and tight programs.
Anchors lock into cone-shaped recesses drilled in the panel back, leaving the face clean. The panel needs enough thickness at each fixing, so this is decided early.
Best for a clean face with no visible fixings.
Screws, rivets or bolts pass through the face into a support rail. The method is simple, economical and easy to inspect, and the heads become part of the facade pattern.
Best for budget-driven or easily inspected facades.
Stiff FRP shells span large areas and tie to a secondary steel or aluminium subframe. Slotted, adjustable brackets handle tolerance and thermal movement.
Best for large, curved or cantilevered shapes.
Situation |
Typical approach |
|---|---|
Large GRC panels with a concrete look
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Stud frame with gravity and flex anchors
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Repeated panels, fast programs, open joints
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Hook-on rail system
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Clean face with no visible fixings
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Concealed undercut anchors
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Large, curved or cantilevered shapes
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Monocoque FRP on a secondary subframe
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Budget-driven or easily inspected facades
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Visible face fixings
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Fire performance is assessed on the complete wall system: backing wall, supports, insulation, cavity, fixings, sealants and coatings. A good panel can be undermined by a poor cavity detail.
GRC from ShapeShift Technologies is tested to AS/NZS 1530.1 as not deemed combustible, the test the National Construction Code points to for external walls of Type A and Type B construction. FRP is a polymer composite. It achieves Group 1 under AS 5637 and B-s2, d0 under EN 13501-1, which are strong results but not non-combustible. Where a non-combustible external wall is required, specify GRC, and coordinate cavity barriers with the fire engineer early.
Before detailing, settle: external or internal and the fire requirement, panel size and curvature, wind zone and structure, achievable tolerances, concealed or visible fixings, cavity depth and drainage, finish, and mock-up timing.
The most common mistakes are restraining movement, ignoring tolerances, assessing the panel instead of the system, deciding fixings too late, and leaving the manufacturer out of early design.
Design Your Need
