NACE 23.3 – Manufacture of Clay Building Materials | Public Tenders

Definition: NACE 23.3 covers the manufacture of clay building materials such as roof tiles, bricks, floor tiles, wall tiles and other ceramic building products. These products form part of almost every public building project and are found in schools, administrative buildings, sports halls and municipal social housing.

Legal basis: NACE Rev. 2 (Regulation (EC) No 1893/2006) · Last updated: January 2026

What does NACE 23.3 cover?

NACE 23.3 (Manufacture of clay building materials) classifies companies that produce ceramic items for construction — one of the oldest and, by volume, most important building-materials segments in public building works.

Group 23.3 within Section C (Manufacturing) and Division 23 is broken down into several classes:

Clay building materials offer durability, resistance to frost and fire and a favourable environmental balance (mineral raw material, recyclability), making them particularly attractive for sustainable public building projects. Large-format porcelain stoneware increasingly replaces natural stone in prestigious public interiors.

Public tenders: scope of activity NACE 23.3

Clay building materials are an integral part of public building projects — from brick supplies for the structural works of municipal schools to tiled finishes for swimming pools, hospitals and metro stations.

Typical contract types

• New schools and school refurbishments: procurement of bricks, roof tiles and interior tiles for municipal school building projects
• Public baths and sports facilities: slip-resistant ceramic tiles for outdoor pools, sports halls and swimming pools — with specific slip-resistance requirements (R classes)
• Public transport infrastructure: floor coverings and wall cladding for metro stations, platforms and underpasses (freeze-thaw cycles, cleanability)
• Administrative buildings: tiles and panels for entrance areas, stairwells and sanitary rooms of public administrative buildings
• Heritage-building refurbishments: reproduction tiles and historic clinker bricks for restoration of listed buildings
• Roof refurbishments of public buildings: roof tiles for municipal buildings, churches in municipal ownership and public housing associations

Thresholds and procurement procedures

Clay building materials are predominantly tendered as part of construction projects in lots (tile and panel work as a separate specialist lot under VOB/A). For EU-wide tenders, the works thresholds apply (EUR 5,538,000). Pure material supplies are subject to the supply thresholds (EUR 221,000).

Relevant CPV codes for NACE 23.3

The following CPV codes allow targeted searches for tenders for clay building materials on TED and national procurement platforms.

Current tenders are published on TED (Tenders Electronic Daily), on municipal procurement platforms and on the federal procurement platform.

For whom is NACE 23.3 relevant in procurement law?

Public contracting authorities

The key contracting authorities for clay building materials are municipal building departments and school and sports-construction agencies, public housing associations for retrofit projects, municipal swimming-pool operators for indoor and outdoor pools, public transport operators for railway stations, heritage-protection authorities for the restoration of historic buildings, and federal authorities for the refurbishment of federal buildings (Federal Real Estate Agency, BImA).

Companies and bidders

Manufacturers of clay building materials and specialist tile wholesalers acting as bidders should consider:

• CE marking and standards: EN 14411 for ceramic tiles and flags, EN 771-1 for masonry units — CE marking under the Construction Products Regulation is mandatory
• Slip-resistance classes: R classes under DIN 51130 and DGUV Rule 108-003 for commercially used floors; particularly relevant for schools, baths and public kitchens
• Frost resistance: classification under EN ISO 10545-12 for outdoor applications (terraces, entrance areas, public transport areas)
• Sustainability and EPD: Environmental Product Declarations (EPD) in accordance with EN 15804 are increasingly required for sustainable public procurement
• Delivery reliability: procurement security for larger lot sizes (capacity evidence), particularly for special formats and reproduction tiles

NACE 23.3 in context: Section C and Division 23

NACE 23.3 is the largest ceramics segment by volume within Division 23 and is closely linked through building works to municipal investment programmes.

• NACE C – Manufacturing: parent section
• NACE 23 – Manufacture of glass, ceramics and other non-metallic mineral products: parent division
• NACE 23.4 – Manufacture of other porcelain and ceramic products: sanitary ware, laboratory porcelain
• NACE 23.5 – Manufacture of cement, lime and plaster: complementary mineral building materials
• NACE 41 – Construction of buildings: main consumer of clay building materials

Frequently asked questions on NACE 23.3 and public tenders

Are tiles tendered as supplies or works? The mere supply of tiles is a supply contract. Where the supply is combined with laying works (substrate, adhesive, grouting) — which is often the case in practice — it constitutes a works contract to be tendered under VOB/A.

What slip-resistance class is required for public swimming pools? For barefoot areas in baths, the rating group under DGUV R 108-003 (barefoot zone) applies: generally Class B or C (vertical, horizontal and on slopes). The specific requirement follows from the use of the space and must be specified in the specification.

Can special tiles outside EU standards be procured for listed buildings? For heritage-protection requirements, exceptions to standard CE requirements can be approved by the building authority. In such cases, coordination with the heritage authority is obligatory, and the specification must reflect the specifics of the historic reproduction materials precisely.

Last updated: January 2026 All information provided without warranty. For legally binding advice, please consult a law firm specialising in public procurement.