It is not possible to fairly assign a single number of years of service life to all panels with wool. Durability is determined by operating conditions, the coating and the execution of joints. What happens after building handover is also important. A well-selected panel can retain its functions for a long time if its edges remain dry and damage is noticed early. A sandwich panel combines steel facings with a wool core. The external surface is exposed to sun, water and contamination. The internal surface works under indoor conditions. The core should remain covered. The durability of the wall depends on the interaction of all these parts and the joints between panels.

One hundred millimetres is a specific core dimension, but not yet a full wall specification. Panels with mineral wool of this thickness can differ in weight, insulation performance and joint. The choice should cover the entire variant and the installation method. Below we show how to assess 100 mm without treating this value as an automatic standard for every building. A 100 mm panel can have different mineral wool density and facing thicknesses. This affects weight and performance characteristics. The joint type can also differ. A variant with concealed fixing does not have to have the same U-value as a panel with visible screws. Do not combine the most favourable figures from several data sheets into one fictitious product.

A wall made of insulated wall panels with a mineral wool core goes up quickly, but its properties depend on the entire solution. Mineral wool is one possible core. When choosing, the steel sheets, joints and supports also matter. This guide leads from how a small building is used to delivery acceptance and later inspections. Two thin facings are bonded to the core. The interaction of these parts allows loads to be transferred within the range specified for the product. Panels with mineral wool use, among other things, a lamella arrangement. In it, the fibres are oriented mainly perpendicular to the facing surfaces. It is not a loose mat inserted between two steel sheets.

A mineral core alone is not enough to assign class A1 to the whole panel. The adhesive and facings must also be assessed. For many complete insulated wall panels with a mineral wool core, class A2-s1,d0 is declared. This must be distinguished from the fire resistance of the finished wall. This information describes different material behaviour and the two cannot be substituted for each other. Reaction to fire describes the product's contribution to fire development under specified test conditions. The classification is read for the specified product. In a sandwich panel, that product is the element with core, adhesive and facings. The parameter of the mineral wool alone is not automatically the parameter of such an assembly.

Lambda describes heat conduction through a material. The U-value relates to the element or building component under consideration. In a sandwich panel, these quantities should not be used interchangeably. Selecting the thickness requires checking the parameter of the finished variant and the joints in the building. Below we show what can really be inferred from a catalogue figure. Lambda, written as λ, expresses a material's ability to conduct heat. It is given in W/(m·K). A lower value means greater resistance of a layer of the same thickness. However, it does not describe the entire panel with its facings, joint and surface heat transfer conditions.

Two 100 mm insulated wall panels with a mineral wool core can have different prices and different properties. The price is affected by the facings, the coating, the fixing and the delivery conditions. A comparison only makes sense once the parameters have been aligned. It is also worth calculating the cost of the finished wall. A cheap panel in a non-matching size may require extras that eat up the initial saving. First establish the type of core and its thickness. Then check both facings, the type of coating and the fixing method. A panel with a visible fastener and a panel with a hidden lock may belong to different families. Their prices do not describe the same solution. A similar colour does not even out these differences.