The Designated Concrete Catalogue
Designated Concrete (see Designated vs Designed Concrete) is specified from a fixed catalogue of standard designations, each aimed at a family of common applications. This page introduces the main designation families and their typical use.
GEN — general and foundation use
The GEN series (GEN1–GEN4, increasing in strength) covers general and mass concrete applications not directly exposed to reinforcement-corrosion risk — blinding, mass fill, kerb bedding and similar low-risk uses, roughly increasing in strength class through the series.
RC — reinforced concrete
The RC series (for example RC20/25 up to RC40/50, named after their associated strength class) covers reinforced concrete for building and general structural use across a range of carbonation-related exposure conditions, and is one of the most commonly specified designated concrete families.
FND — foundations in aggressive ground
The FND series (FND2–FND4) is aimed specifically at foundation concrete in chemically aggressive ground or groundwater conditions, corresponding to increasing design chemical class (DC-class) severity assessed for the site.
PAV — pavement concrete
The PAV series (PAV1, PAV2) covers pavement-quality concrete such as roads and hardstanding, where freeze-thaw resistance and abrasion resistance from trafficking are relevant considerations alongside strength.
Relating designations to strength class
Each designated concrete’s name and its associated strength class are closely related but not identical concepts — for example RC25/30 is closely associated with strength class C25/30, but the designation also carries a pre-approved combination of exposure suitability, consistence range and cement type suitable for common use, which a bare strength class does not by itself. See the class-specific pages, for example C25/30 concrete, for how each strength class maps to its typical designated concrete equivalent.
Frequently asked questions
Can I just ask for ‘RC25/30’ instead of specifying exposure class myself?
Largely yes for common, well-understood conditions — that is the point of Designated Concrete: the designation already bundles a pre-approved combination of properties suitable for its intended applications. For anything outside the designation’s intended scope, Designed Concrete is used instead.
What if my project doesn’t fit any of GEN/RC/FND/PAV?
Then Designed Concrete is the appropriate route — you specify the performance requirements directly and a producer designs a mix to meet them. See Designated vs Designed Concrete.
Are the exact composition limits for each designation fixed?
The designation names and their intended applications are stable reference points, but the underlying composition and durability requirements sit in BS 8500-2’s current designation tables — check those directly for a live project rather than assuming a fixed recipe.