For the majority of common applications the most convenient way to specify a concrete mix is to use a designated concrete. Designated concrete mixes for various applications are described with a simple code number; this code allows the mix required to be easily communicated to the supplier. There are designated mixes suitable for a wide range of housing, structural and other applications. Producers of designated concrete must have in place a system of third party accreditation for their production control and product conformity. This accreditation allows the customer to be confident that concrete supplied with be suitable for the required application.
| Application |
Designated Mix |
Recommended Consistence Class |
| Unreinforced foundations and associated works requiring design chemical class 1 (DC-1) |
| Drainage works to give immediate support |
GEN1 |
S1 (10-40mm) |
| Blinding and mass concrete fill, strip footings, mass concrete foundations, oversite below suspended slabs, other drainage works |
GEN1 |
S3 (100-150mm)* |
| Trench fill foundations |
GEN1 |
S4 (160-210mm) |
| Unreinforced foundations requiring DC-2 to DC-4 concrete |
| DC-2 foundations |
FND2 |
S3 (100-150mm)*† |
| DC-2z foundations |
FND2Z |
S3 (100-150mm)*† |
| DC-3 foundations |
FND3 |
S3 (100-150mm)*† |
| DC-3z foundations |
FND3Z |
S3 (100-150mm)*† |
| DC-4 foundations |
FND4 |
S3 (100-150mm)*† |
| DC-4z foundations |
FND4Z |
S3 (100-150mm)*† |
| DC-4m foundations |
FND4M |
S3 (100-150mm)*† |
| General applications |
| Kerb bedding and backing |
GEN0 |
S1 (10-40mm) |
| Floors |
| House floors with no embedded metal, permanent finish to be added, eg a screed or floating floor |
GEN1 |
S2 (50-90mm) |
| House floors with no embedded metal, no permanent finish to be added, eg carpeted |
GEN2 |
S2 (50-90mm) |
| Garage floors with no embedded metal |
GEN3 |
S2 (50-90mm) |
| Wearing surface: light foot and trolley traffic |
RC25/30 |
S2 (50-90mm) |
| Wearing surface: general industrial |
RC32/40 |
S2 (50-90mm) |
| Wearing surface: heavy industrial |
RC40/50 |
S2 (50-90mm) |
| Paving |
| House drives and domestic parking |
PAV1 |
S2 (50-90mm)* |
| Heavy-duty external paving with rubber tyre vehicles |
PAV2 |
S2 (50-90mm)* |
* This is the default slump class for this designated concrete
† For trench fill, the recommended consistence class is S4 (160-210mm)