Flexible Stone Veneer Glossary: 25+ Terms Every Specifier Should Know
Specifying MCM flexible stone
veneer means moving between material science, fire codes, trade documents, and installation
systems. The vocabulary crosses at least four standards families, and a single misunderstood
term — “A2” versus “A2-s1,d0”, or “FOB” versus “CIF” — can change a specification, a quote,
or a code approval. This glossary collects the definitions specifiers, contractors, and
procurement teams actually need, written to be quotable and machine-readable.
Use it as a reference while reading our
specifications page or
our import buyer’s
guide. Terms are grouped by theme; each is self-contained so it can be cited on its own.
Product & Material Terms
MCM (Modified Clay Material)
MCM stands for Modified Clay Material — a family of factory-made cladding made from
naturally sourced mineral powders (stone, clay, quartz) modified with a small proportion of
polymer modifiers and formed under controlled temperature and pressure. The result is a
flexible, lightweight sheet that carries a genuine stone/mineral surface without the weight
or brittleness of quarried stone. TooFlexi produces MCM flexible stone in 400+ textures.
Flexible Stone Veneer
A thin, bendable surfacing sheet with a mineral face and a flexible backing, supplied in
tiles or panels rather than rigid slabs. “Veneer” here means a thin facing layer, not a
wood product. Flexible stone veneer is applied to walls, columns, and curved substrates with
adhesive, and is valued for low weight (3.0–10.5 kg/m²) and the ability to wrap radiused
forms that rigid stone cannot.
Thin Stone Tile / Thin Veneer
A general term for stone-faced tiles thinner than traditional 10–20 mm masonry veneer.
MCM flexible stone sits in this category at 2–9 mm, which is meaningfully thinner and far
lighter than sawn thin-stone (often 4–6 mm and brittle) or full-bed stone.
Mineral-Polymer Matrix
The composite that gives MCM its flexibility: mineral powders bound by a low-load polymer
modifier. The mineral content is what delivers the A2-s1,d0 fire classification; the polymer
modifier (not a resin binder) provides flex rather than combustibility. This is distinct from
polyurethane- or acrylic-bound panels, which classify lower.
Texture / Series
Manufacturers organise colour and relief patterns into series. TooFlexi’s range spans
Rock, Line, Simulation, and High-End series across 400+ textures, each with a stable product
code used in quotes and orders.
Fire Safety & Certification Terms
A2-s1,d0
The full European-style reaction-to-fire classification string. Breaking it down:
A2 = limited combustibility; s1 = limited smoke production;
d0 = no flaming droplets or particles. A supplier quoting plain “A2” without
the s and d suffixes is omitting half the classification. TooFlexi MCM flexible stone is
A2-s1,d0 class (GB 8624, factory tested).
A2 (Limited Combustibility)
A2 means limited combustibility — it is the highest practical class for a
mineral-based cladding panel and sits directly below A1 (non-combustible). A2 is not the same
as “non-combustible”; the distinction matters for building codes that set height thresholds
above which only A2-s1,d0 or better is permitted.
s1 / d0 (Smoke & Droplets)
Suffixes attached to a fire class. s1 indicates minimal smoke production
during combustion; d0 indicates no burning droplets that could spread fire.
Both are relevant in enclosed or evacuation-sensitive spaces such as hospitals, schools, and
transport hubs.
GB 8624
The Chinese national standard for classification of burning behaviour of building
materials. Its 2012 revision is harmonised with the EN 13501-1 tiers, so an A2 result under
GB 8624 aligns with the European A2-s1,d0 expectation. TooFlexi products are A2 class (GB
8624, factory tested); classification documentation can be specified to meet EN 13501-1
A2-s1,d0 for projects that require the European reference.
EN 13501-1
The European harmonised standard for reaction to fire, classifying construction products
from A1 (non-combustible) to F. It defines the A2-s1,d0 string used throughout this glossary.
For projects specifying the European framework, TooFlexi MCM flexible stone can be specified
to meet EN 13501-1 A2-s1,d0; the underlying GB 8624 A2 result supports that alignment.
ASTM E84 (Class A)
The U.S. Steiner Tunnel Test measuring flame spread and smoke development. TooFlexi MCM
panels test as Class A (flame spread index well below the 25 threshold),
qualifying them for demanding interior locations including exit corridors under the
International Building Code.
CE Marking
The conformity mark required for construction products placed on the European market. For
MCM cladding it is supported by fire-classification documentation and declared performance
under the Construction Products Regulation. See our
certification
guide for the document set.
ISO 9001 / ISO 14001
International standards for quality management (ISO 9001) and environmental management (ISO
14001). A manufacturer holding both signals documented, repeatable processes and controlled
environmental impact — useful procurement filters when vetting a factory.
Dimensions & Physical Properties
Thickness (2–9 mm)
MCM flexible stone is supplied in the 2–9 mm range, with most architectural patterns at
2–9 mm and heavier-relief or exterior grades up to 9 mm. Thickness affects weight, substrate
transition, and (for fire) the tested assembly range — confirm the classification covers your
specified thickness.
Weight (3.0–10.5 kg/m²)
Surface weight of the finished sheet. At 3.0–10.5 kg/m², MCM is a fraction of quarried
stone (40–80 kg/m²) and light enough for over-cladding existing walls and for seismic- or
load-limited structures. Compare in our
vs-alternatives table.
Sheet Size
Standard panel formats are 600 × 1200 mm and 1200 × 2400 mm. Larger sheets speed
installation on open façades; smaller formats suit feature walls and detailed areas. Always
confirm available sizes per texture, as not every code is offered in both formats.
VOC (Volatile Organic Compounds)
VOCs are gases emitted by some building materials. Cured MCM emits no significant VOCs,
supporting indoor air-quality requirements in healthcare, education, and office fit-outs, and
contributing to green-building credits.
Trade, Logistics & Compliance
HS Code 6810.19
The Harmonized System code commonly applied to MCM/stone-composite cladding panels for
customs classification. HS headings can vary by destination and by exact composition, so
confirm the applicable subheading with a licensed customs broker for your shipment — do not
treat this as a guarantee for every border.
FOB Shenzhen
Free On Board Shenzhen — the standard shipment terms for TooFlexi exports. Under FOB, the
seller delivers the goods onto the vessel at the Shenzhen port; risk and freight responsibility
transfer to the buyer at that point. FOB Shenzhen is the baseline for most quotes.
CIF
Cost, Insurance and Freight — a quoted term where the seller also arranges and pays ocean
freight and minimum insurance to the destination port. CIF is available on request and is
useful when a buyer prefers the supplier to manage the sea leg.
MOQ (Minimum Order Quantity)
The smallest production run a factory will accept. TooFlexi’s standard MOQ is 200 m² per
colour, accessible for pilot projects while still supporting volume commercial orders. Custom
colours or textures may carry a higher MOQ.
Lead Time
The production window from order confirmation to ready-for-shipment. TooFlexi standard
orders run approximately 20–25 working days; complex custom colours or very large volumes may
extend. Build lead time into project programmes and shipping buffers.
Certificate of Origin (CO)
A document stating where goods were manufactured, required by customs in many destinations
and used to claim preferential tariffs (e.g., Form E for ASEAN, Form F for certain partner
markets). The CO is issued per shipment.
SGS / TÜV / Intertek
Accredited third-party testing and certification bodies. Independent reports from laboratories
such as SGS, TÜV, or Intertek carry more weight with building-control authorities than
manufacturer-produced statements. Request the original, numbered report — not a summary.
Installation & Application
Substrate
The surface the panel is bonded to — concrete, cement board, plaster, existing tile, or
render. MCM adheres to a wide range of sound substrates; combustibility of the substrate
also decides the fire performance of the installed wall, not the loose panel alone.
Adhesive / Mortar
The bonding layer. Use polymer-modified cementitious adhesives tested with the panels; an
untested adhesive can compromise the assembly’s fire classification and long-term bond.
Installation detail is covered in our
installation guide.
By substrate, which family to use where is set out in our
adhesive selection guide.
Curved Surface
Radiused walls, columns, and arches. MCM’s flexibility lets it wrap curves that rigid stone
cannot, typically without mitring or wet-forming — a key reason specifiers choose it for
columns and feature elements.
Rainscreen / Ventilated Façade
An exterior wall build-up where the cladding sits off the structure with a ventilated cavity
behind it, draining and drying any infiltrated water. MCM is used in both ventilated
rainscreen systems and direct-adhered exterior applications depending on the project.
Frequently Asked Questions
What does MCM stand for in flexible stone?
MCM stands for Modified Clay Material — mineral powders modified with a small polymer
content and formed into flexible, lightweight cladding sheets. It is the technology behind
TooFlexi flexible stone veneer.
Is A2 the same as non-combustible?
No. A2 means limited combustibility and sits just below A1 (non-combustible). For
many high-rise and public-building codes, A2-s1,d0 is the required minimum, not A1.
What is the difference between GB 8624 and EN 13501-1?
GB 8624 is the Chinese national fire-classification standard; EN 13501-1 is the European
one. The GB 8624 (2012) revision is harmonised with EN 13501-1 tiers, so a GB 8624 A2 result
aligns with the European A2-s1,d0 expectation. TooFlexi products are A2 class (GB 8624,
factory tested) and can be specified to meet EN 13501-1 A2-s1,d0.
How heavy is flexible stone veneer per m²?
Finished MCM flexible stone weighs 3.0–10.5 kg/m², compared with 40–80 kg/m² for quarried
stone veneer — roughly one-tenth the load, which is why it suits over-cladding and
load-limited structures.
What HS code applies to flexible stone veneer?
MCM/stone-composite cladding panels are commonly classified under HS 6810.19, but the exact
subheading can vary by destination and composition. Confirm with a licensed customs broker
for your specific shipment.
What do FOB and CIF mean for an order?
FOB Shenzhen means the seller delivers goods onto the vessel at Shenzhen port; the buyer
takes over freight and risk from there. CIF adds ocean freight and minimum insurance to the
destination port, arranged by the seller. TooFlexi quotes on FOB Shenzhen by default, with
CIF available on request.
What thickness and sheet sizes are standard?
Standard thickness is 2–9 mm (most patterns 2–9 mm) and standard sheet sizes are 600 × 1200
mm and 1200 × 2400 mm. Availability of both sizes varies by texture.
Which third-party labs should verify test reports?
Reports from accredited bodies such as SGS, TÜV, or Intertek are preferred. Always request
the original, numbered report and verify the issuing body directly rather than accepting a
summary PDF.
For product selection and project specification, browse the
TooFlexi product range or review the full
technical specifications.
Architects and specifiers can request documentation through the
contact page.
