23/10/2026
Part 1: Definitions, Specifications and Conformity Criteria
Building lime is obtained by heating limestone (CaCO₃) at high temperatures of 900–1,000°C. It is a natural building material that complies with EN 459-1:2010 and is used as a binder in mortar, plaster and soil stabilization in the construction industry. It is environmentally friendly and breathable. The standard covers lime products used in construction, building and civil engineering applications and materials. These products are divided into two main groups: air lime, which hardens in air, and lime with hydraulic properties.
Differences in raw material sources and climatic conditions across Europe have led to the development of different practices in construction, civil engineering applications and materials, and consequently to the development of different types of building lime.
The wide range of building limes available in Europe has made it necessary to establish a defined set of classes.
Previous national standards for building lime have often also served as a basis for other applications. These conditions have therefore been considered as far as possible in the classification adopted.
To distinguish between the two groups more clearly, this standard makes an explicit distinction between air lime and lime with hydraulic properties. Depending on their composition and characteristics, each group is divided into subcategories with corresponding definitions, specifications and conformity criteria: calcium lime and dolomitic lime for air lime; and natural hydraulic lime, formulated lime and hydraulic lime for lime with hydraulic properties.
European Standards for Building Lime Products
Building lime products covered by EN 459-1 include building limes intended for use in the following applications:
- As a binder in mortars, for example, for masonry and internal and external plastering;
- In the manufacture of other building materials, such as sand-lime bricks, autoclaved aerated concrete and concrete;
- In civil engineering applications, such as soil improvement and asphalt mixtures.
This standard defines and classifies the different types of building lime. It also specifies the requirements for the chemical and physical properties of each type of building lime, together with the applicable conformity criteria.
Applications of Building Lime
- Restoration of historic buildings
- Internal and external plastering
- Masonry and jointing mortars
- Foundations and structures exposed to water
- Modern construction and industrial applications
- Structural implications of material selection
Beyond its traditional uses, building lime plays an important role in modern construction technology. Selecting the appropriate type of lime can deliver benefits in terms of strength, sustainability, building physics and environmental compatibility. Classifications such as NHL, FL and HL help optimize material performance according to the requirements of each application. The informed use of lime-based binders therefore provides sustainable and durable solutions for both restoration and modern construction.
Avcp System: Ensuring Constancy of Performance
The Assessment and Verification of Constancy of Performance (AVCP) system is used under the Construction Products Regulation (CPR), Regulation (EU) No 305/2011, to ensure that construction products consistently maintain their declared performance. It provides a framework for verifying product performance and ensuring the reliability of declared characteristics.
| AVCP System | Manufacturer’s Responsibilities | Notified Body’s Responsibilities |
| System 2+ | Factory Production Contro(FPC)Determination of the Product Type: Type testing, including sampling; type calculation; tabulated values; or descriptive documentation of the productFurther testing of samples taken at the factory in accordance with a prescribed test plan. | Initial inspection of the manufacturing plant and Factory Production Control (FPC)Continuous surveillance, assessment and evaluation of FPC. |
Efectis is pleased to announce that it has recently been designated as a Notified Body for Factory Production Control under AVCP System 2+ for building lime products.
This important authorization expands our conformity assessment and certification services for the relevant product groups in accordance with European Union legislation, further strengthening our ability to provide our customers with reliable solutions that meet international standards.
Drawing on Efectis’s technical expertise and impartial approach, we will continue to create value for industry stakeholders and contribute to quality assurance in the construction products sector.