EN 1603 Thermal Insulation Products for Building Applications - Determination of Dimensional Stability Under Normal Laboratory Conditions

The European standard "EN 1603 Thermal insulation products for building applications - Determination of dimensional stability under constant normal laboratory conditions (23 degrees Celsius/50 percent relative humidity)" describes the equipment and procedures required to evaluate irreversible dimensional changes in test specimens and full-size products over time under constant normal laboratory conditions. This standard also applies to thermal insulation products.

For the purposes of this standard, the following terms and definitions apply:

• Length: It refers to the long linear dimension of the main surface of the test specimen parallel to the long linear dimension of the original product.
• Width: It refers to the short linear dimension of the main surface of the test specimen measured at right angles to the length.
• Deviation from flatness: It refers to the maximum distance between the product placed on a flat surface with the convex side up and the flat surface.
• Normal laboratory conditions: 23 degrees plus/minus 2 degrees temperature and 50 percent plus/minus 5 percent relative humidity.

In principle, under normal laboratory conditions, the length, width, and flatness of test specimens are measured at several time intervals until relative stability is achieved. Dimensional stability is determined using one or more of the methods given in the standard:

• Method A: Determination of linear dimensions of full-size products
• Method B: Determining the linear dimensions of products using test samples with dimensions smaller than full-size products
• Method C: Determining the deviation from flatness of full-size products.

The equipment used in these tests is:

• Method A: Measuring equipment defined in the EN 822 standard.
• Method B: A dial clock with a precision of 0,01 mm or any device (optical, electrical) with a precision of 0,1 mm/m and a bezel fixed to a flat reference surface.
• Method B1: Metal plates with a minimum diameter of 20 mm. The actual diameter should be selected so that the pressure exerted by the dial watch is less than 2 kPa.
• Method B2: Metal wire.
• Method C: Measuring equipment defined in the EN 825 standard.

Any testing equipment that provides at least the same result with the same accuracy can be used.

The thickness of the test samples should be equal to the thickness of the original product.

• Method A: The test sample should be the full-size product.
• Method B1: If less than 500 mm x 500 mm or 500 mm x 500 mm, it should be as large as possible. In any case, it should be greater than 250 mm x 250 mm.
• Method B2: Should be 250 mm x 250 mm.
• Method C: The test sample should be the full-size product.

When testing full-size products, the number of test samples must be the number specified in the relevant product standard. If measurements are made on test samples taken from a full-size product, at least three test samples must be tested. In the absence of a product standard or other European technical specification, the number of test samples may be agreed upon between the parties.

The EN 1603 standard measures irreversible dimensional changes (e.g., shrinkage or swelling) in thermal insulation products under constant climatic conditions (23 degrees Celsius and 50 percent relative humidity). These can be foam boards, mineral wool panels, or cork boards.

Dimensional stability is a critical property in insulation materials; even small shrinkage can lead to voids or thermal bridges, reducing performance (for example, polyurethane foam shrinkage should remain below 1 percent). The EN1603 standard ensures consistent and comparable measurements across manufacturers during quality control and product certification processes.

The EN 1603 standard is part of a larger series covering various thermal-mechanical tests such as density (EN 1602), compressive creep (EN 1606) and tensile strength (EN 1607).

The EN 1603 standard is important because it ensures the dimensional stability of thermal insulation products used in building applications. In practice, it helps ensure that insulation materials do not shrink, swell, or deform over time under normal indoor conditions. The main reasons for the importance of this standard are:

• Maintains energy efficiency: Even the slightest shrinkage in insulation materials can create gaps between panels or boards. These gaps allow heat to escape or enter, reducing the building's thermal performance, which defeats the purpose of insulation.
• Prevents thermal bridges: Poor dimensional stability leads to thermal bridges, areas where heat flows more easily due to missing or poorly installed insulation. This leads to higher heating and cooling costs and reduced user comfort.
• Supports long-term building performance: this standard tests for permanent (irreversible) dimensional changes. By choosing products that meet this standard, architects and contractors ensure that insulation performs as expected for decades, not just the first few years after installation.
• Ensures fair comparison between products: This provides a standardized testing method so manufacturers can prove that their products meet quality criteria and buyers can reliably compare products.
• CE marking supports regulatory compliance: In European Union countries, construction products must generally comply with construction product regulations. EN 1603 is one of the harmonized testing standards used to demonstrate product performance and achieve CE marking.
• Quality assurance for installers and builders: Installers can be confident that materials tested to this standard will not deform and cause installation problems later on (e.g. boards lifting, shrinking or cracking under the cladding).

Our organization, which has been supporting businesses across all sectors for years through a wide range of testing, measurement, analysis, and evaluation activities, boasts a strong team of employees who closely follow global developments in science and technology and are constantly improving themselves. In this context, we also provide testing services in accordance with the standard "EN 1603 Thermal insulation products for building applications - Determination of dimensional stability under fixed standard laboratory conditions (23 degrees Celsius / 50 percent relative humidity)."