Facade selection guide · evidence before advantage
Terracotta rainscreen decisions: define the system, evidence and responsibility
A fired-clay panel can be one part of a rainscreen facade; it is not the whole wall. Selection should connect the exact panel and supports to the project’s structural, water, fire, thermal, acoustic, weathering, appearance, access and environmental requirements.
- Archive date
- 26 August 2016
- Historic diagram concept
- Outer terracotta panel, cavity and inner/backing wall
- Historic product data
- No item, dimensions, support layout or test values supplied
- Primary decision unit
- The defined complete facade assembly, not the panel alone
- Project evidence
- Current, configuration-specific and jurisdiction-relevant
- Approval outcome
- Assigned to named project parties under the actual contract
Separate product, support system and wall assembly
Many claims become misleading because “terracotta rainscreen” is used for three different scopes. A decision record should name what is included at each level and identify the interfaces that another party must design.
Terracotta product
Panel body, geometry, cavities or webs, grooves, edges, surface, colour, dimensions, tolerances, unit mass, production lot and applicable product evidence.
Supports and attachments
Clips, rails, brackets, anchors, fasteners, pads, restraints, adjustment and any fragment-retention component—only where these are in the documented supply scope.
Complete wall
Backing structure, sheathing, air/water layers, insulation, cavity, barriers, flashings, openings, interfaces and interior layers, coordinated with the cladding and supports.
Decision and evidence matrix
For each topic, write a project criterion first, then request evidence that identifies the exact product or assembly, test method and edition, specimen and support configuration, result, date, issuer and limitations. A marketing adjective is not a pass criterion.
| Decision topic | Define for the project | Evidence to request and review | Do not infer |
|---|---|---|---|
| Product identity | Item, clay body, profile, surface, colour, dimensions, tolerances, mass and production range. | Controlled current data sheet, drawings, representative samples, lot controls and declared limitations. | That any LOPO panel shares the same properties or fits the same supports. |
| Structural actions | Self-weight, wind zones, seismic action where relevant, impact, maintenance loads, building movement and governing combinations. | Project calculations, component/assembly tests where required, substrate verification and signed coordinated drawings. | Universal support spacing, anchor capacity, panel span, redundancy or post-breakage safety. |
| Water and air | Rain-management principle, inner air/water control layers, cavity drainage/venting, compartments, flashings and interfaces. | Complete details, continuity review, representative air/water testing and documented field checks appropriate to the project. | That open joints make the wall watertight or automatically pressure-equalized. |
| Fire and cavity | Applicable wall classification, material limits, cavity barriers/fire stopping, penetrations, floor lines and interface conditions. | Current product and assembly reports/approvals covering the actual materials, arrangement, supports and jurisdiction. | That a fired-clay face makes every insulation, membrane, clip, adhesive and cavity configuration compliant. |
| Thermal and moisture | Whole-wall target, continuity of insulation, thermal bridges, interior/exterior climate, condensation criteria and movement from temperature. | Whole-wall calculations or modelling with project geometry and material inputs; interface and condensation review. | Energy savings, indoor comfort, lower cooling cost or absence of condensation from the cavity or panel alone. |
| Acoustics | Required airborne and exterior-noise performance, flanking paths, openings and interior build-up. | Assembly-level laboratory or project analysis covering the relevant wall and junctions. | A whole-wall acoustic value from hollow-panel geometry or material description. |
| Weathering and freeze–thaw | Exposure, moisture regime, temperature cycling, salts/pollutants, surface and project acceptance criteria. | Current test reports for the exact body/surface and representative condition, plus project-specific detailing and maintenance assumptions. | Permanent performance, universal freeze resistance or suitability for every climate. |
| Colour and appearance | Target colour/surface, acceptable range, orientation, joint shadow, corner/cut appearance, replacement and weathering expectations. | Physical samples, range boards, dated approvals, production-lot plan, mock-up and documented viewing conditions. | “Never fades,” exact screen-to-fired colour or invisible batch variation. |
| Maintenance and replacement | Access, inspection triggers, cleaning, damage criteria, replacement sequence, neighbouring-panel effects and spare stock. | Project maintenance manual, safe access plan, approved cleaning trials, replacement demonstration and traceable spares. | Maintenance-free operation, no future sealant work or easy replacement for every detail. |
| Environmental documentation | Assessment boundary, project rating or procurement requirement, transport, service assumptions and end-of-life scenario. | Current third-party environmental declarations or equivalent documents with programme, date, geography, product coverage and declared unit clearly stated. | That “natural clay,” recyclability or a long service claim proves a product is green or lowers whole-building impact. |
How the 2016 “advantages” claims should be tested
Energy and condensation
- Model the complete wall and actual interfaces.
- Use defined interior/exterior conditions and material inputs.
- Resolve slab edges, brackets, anchors, openings and parapets.
- Report whole-wall results and condensation risk, not a panel-only benefit.
Water management
- Trace deflection, entry, drainage and drying paths.
- Detail the inner water/air control layer continuously.
- Coordinate joints, vents, compartments, flashings and terminations.
- Set project test pressures and acceptance through the responsible team.
Impact and replacement
- Define exposure and impact categories for each elevation zone.
- Check panel, supports and post-breakage behaviour together.
- Demonstrate removal and replacement at representative details.
- Plan access, isolation, matching stock and inspection after an event.
Installation and programme
- Name the competent specialist installer and supervisory roles.
- Issue project-specific method statements, tolerances and hold points.
- Plan access equipment, weather limits, storage and lifting safely.
- Base time and cost on the actual design, quantities, logistics and labour—not a generic comparison with stone or brick.
Colour and maintenance
- Approve a physical colour/surface range and mock-up.
- Define cleaning agents, method, access and trial area.
- Record lots and retain appropriately stored replacement units.
- Review joints, interfaces and adjacent materials as well as panels.
Fire, acoustics and environmental claims
- Use complete-assembly fire evidence and cavity strategy.
- Use complete-wall acoustic evidence for the relevant spectrum and junctions.
- Check environmental-document dates, scope and declared units.
- Keep product declarations separate from whole-building outcomes.
Move from sample to project evidence in stages
Brief and responsibility map
Issue performance, appearance, regulation, programme and maintenance criteria. Name the designer, supplier, engineers, specialist contractor, testers, reviewers and final decision owners for each interface.
Product and range samples
Confirm the proposed body, surface, colour, geometry and variability using physical samples. Keep approval dates, identifiers, viewing conditions and retained controls.
Coordinated technical design
Resolve elevations, supports, anchors, substrate, movement, openings, cavity, barriers, drainage, fire stopping, access and replacement before test specimens are fixed.
Representative testing
Use the intended configuration and defined acceptance criteria. Record deviations and determine whether a result covers every project zone or only the tested arrangement.
Visual and technical mock-up
Review colour range, joint rhythm, corners, cuts, openings and adjacent materials while checking buildability, tolerances, drainage, access and replacement.
Installation QA and handover
Trace materials and lots, inspect substrate and engagement, close non-conformances, record as-built locations, and hand over access, cleaning, inspection, replacement and spares information.
Make responsibility explicit
| Scope | Question to close before approval | Record required |
|---|---|---|
| Panel supplier | Which panels, surfaces, colours, dimensions, tolerances, lots, samples, documents and replacement units are in supply? | Controlled schedule, data, approvals, packing/traceability and exclusions. |
| Support-system supplier | Are clips, rails, brackets, fasteners or restraints supplied, and who verifies their compatibility and capacity? | Component scope, drawings, material data, tests where required and interface limits. |
| Facade / structural design | Who owns panel/support calculations, subframe, anchors, backing structure, movement, tolerances and post-breakage strategy? | Signed design basis, calculations, coordinated drawings and review status. |
| Envelope / fire design | Who owns the air/water layers, drainage, insulation, thermal bridges, condensation, cavity barriers, fire stopping and penetrations? | Coordinated wall details, analysis, reports and approvals for the project build-up. |
| Specialist contractor | Who verifies substrate, setting-out, components, panel engagement, damage, tolerances and corrective work? | Method statement, inspection/test plan, hold points, site records and as-builts. |
| Owner / maintenance team | Who funds and performs access, inspection, cleaning, incident review, replacement and stock control? | Handover manual, baseline survey, access plan, trigger-based schedule and spare register. |
Continue with current product and document context
Use current pages to discuss available products and documents, then confirm that every file actually covers the proposed item, support arrangement, assembly and jurisdiction.
Build an evidence request for your facade
Send the project location, building and elevation zones, preliminary panel and support concept, backing wall, performance brief, fire/cavity strategy, appearance reference, required documents, mock-up/testing route, delivery destination and programme. Current products and complete assemblies must be verified for the actual project.