The thermal resistance is the property explaining how well a product resists thermal transmission through the material. This is one of the main reasons to insulate: to reduce unwanted heat losses in installation and building structures. The thermal performance of an insulation material is often given as the thermal conductivity (lambda value). The lower the lambda value is, the better the insulation.

The thermal conductivity (lambda) depends on temperature and moisture. Since lambda is dependent on temperature, it is very important to use the right product for the right application. A product with good (low) lambda value at 10°C might not have a good lambda value at 100°C.

Moisture affects the materials thermal conductivity since water has a much worse lambda value than air. See the table below.

Material	Lambda λ10 -value, W/mK
Stonewool, perpendicular to fibers	0.033 – 0.039
Stonewool, parallel to fibers	0.039 – 0.050
Wood	0.14
Carbon steel	60
Air	0.025
Water	0.6
Ice	2.3

Thermal conductivity of PAROC stone wool products do not change with time, and will keep their thermal properties throughout the lifetime of the installation. Lambda values can be declared by the lambda-temperature curve or in a table with lambda and thermal conductivity values. The unit for thermal conductivity is W/(m x K). The value is rounded up to closest 0.001 W/(m x K). If the product has a declared maximum service temperature, the lambda values shall be declared up to that temperature.

Lambda values declared by Paroc are tested in accordance with the harmonised European standards EN 12667 for flat products and EN ISO 8497 for pipe sections.

Thermal conductivity is not shown in the designation code, but must be visible in the EC Declaration of Conformity and in the product information.

You will find these documents on the product pages.

The reaction to fire classification describes how the product, as placed on market, contributes to fire development in the early phase of a fire. This is called Euroclass, which shall be determined in accordance with EN 13501-1. A material with a good Euroclass delays flashover as long as possible. After that, it is the fire resistance of a structure that is important (e.g. EI classification).

Reaction to fire is described with Euroclass A-F, with the addition of how much smoke (s1-s3) and flaming droplets (d0-d2) the product creates when exposed to fire.

 

	Contribution to fire A - B - C - D - E - F	Smoke intensity s1 - s2 - s3	Burning droplets d0 - d1 - d2
A1	Flashover not possible	No test needed	No test needed
A2	Flashover not possible	s1 = No or very little smoke s2 = Limited amount of smoke s3 = Much smoke	d0 = No burning droplets d1 = Droplets burn for less than 10 sec d2 = No demand
B	Flashover not possible
C	Flashover after more than 10 minutes
D	Flashover between 2 and 10 minutes
E	Flashover in less than 2 minutes	Not tested	- or d2
F	Not tested	Not tested	Not tested

 

Examples of Euroclass

* A2-s1, d0 (Flashover not possible, no or very little smoke, no burning droplets)

* B-s3, d1 (Flashover not possible, much smoke, droplets burn for less than 10 seconds)
For pipes the same Euroclasses are used, but with the subscript index “L” (e.g. A2L-s1, d0).

PAROC stone wool is Euroclass A1 and does not contribute to the development of a fire. The requirement varies depending on national regulations and those vary between European countries. PAROC stone wool reaction to fire does not change over time and gives the same top level, maintenance-free fire safety during the entire lifetime of the installations.

The Euroclass of the product is not shown in the designation code, but shall always be shown on the EC Declaration of Conformity and other product related information (e.g. datasheets and on the product label).

In the dimension and tolerances declaration it is shown what tolerances the product has for different dimensions. The dimensions are length, width and thickness for flat products and, for slabs and boards, squareness. For pipe sections the dimensions are length, thickness, inside diameter, thickness uniformity and squareness.

Thickness tolerances are described as classes from T1 to T9 according to the table below:

Thickness tolerances
Level or class	Tolerances
T1	-5 % or -5 mma	Excess permitted
T2	-5 % or -5 mma	+15 % or +15 mmb
T3	-3 % or -3 mma	+10 % or +10 mmb
T4	-3 % or -3 mma	+5 % or +5 mmb
T5	-1 % or -1 mma	+3 mm
T8	-5 % or -3 mma	+5 % or +3 mma
T9	-6 % or -5 mma	+6 % or +5 mma

a = whichever gives the greatest numerical tolerance.
b = whichever gives the smallest numerical tolerance.

Other dimensional tolerance requirements according to EN 14303 are:

Form of delivery	Width	Length	Thickness class	Inside diameter	Thickness uniformity	Squareness
Slabs/ boards	±1,5 %	±2 %	T3 - T5			±5 mm/m
Lamella mats	±5 mm	+excess -0 mm	T4 ja T5
Wired mats	±10 mm	+excess -0 mm	T2 ja T3
Batts, mats, rolls, quilts, mattress, feltsb	±10 mm	+excess -0 mm	T1 - T5
Pipe sections Do <150 mm		±5 mm	T8	+4 mm -0 mm	Difference less than 6 mm or 10 % a	±4 mm or ±2 % of the external nominal diametera
Pipe sections Do ≥150 mm		±5 mm	T9	+5 mm tai +2 % -0 mm	Difference less than 10 mm or 12 % a	±4 mm or ±2 % of the external nominal diametera

a = whichever gives the greatest numerical tolerance.
b = T2 only.

PAROC stone wool always meets the requirements stated in the standard. Our internal requirements are even tighter.

The thickness tolerance class of, for example, T4 is shown in the designation code like this: T4.

Dimensional stability describes how well dimensions are maintained when the product is exposed to high relative humidity for a longer time (48 hours). The change in thickness, length and width shall not exceed 1.0%. For products where maximum service temperature is declared, the dimensional stability is not needed since the products have been exposed to a more severe test.

Unlike some insulation material on the market, PAROC stone wool does not change with time. Thermal conductivity, reaction to fire and dimensions such as thickness are intact for the lifetime of the installation.

Maximum service temperature is very important in applications where the insulation will be exposed to high temperatures, continuously or in intervals. Especially in industrial applications this is a very important property. In most cases, a high density product can withstand a higher service temperature than a low density product.

Tests shall be carried out in accordance with EN 14706 for flat products and EN 14707 for pipe sections. The product is tested under a load, and the reduction of thickness is measured after the product has been exposed to declared temperature for 72 hours. If the reduction of thickness is less than 5% and there is no evidence of self-heating, the product has passed the test. If a product is used in an application with too high maximum service temperature, there is a risk of, for example, thickness reduction, which gives a worse thermal insulation over time.

When a maximum service temperature of, for example, 680 °C for a product is declared, it is shown in the designation code like this: ST(+)680.

Water absorption is a important property, since there are many applications where the insulation might be exposed to water, high humidity or other liquids, such as at building sites, as well as in case of leakages of tanks, pipes or other equipment. If the insulation absorbs water it might increase damage to the installation e.g. corrosion and also dramatically lower the insulation properties of the product (increase thermal conductivity). Wet insulation does not have the same thermal conductivity properties as declared.

If the water absorption is declared, test results cannot exceed 1.0 kg/m². Tests shall be determined in accordance with EN 1609 for flat products and EN 13472 for pipe sections. When testing, the product is placed in water for 24 hours, dried for 10 minutes and after that, the change in weight is measured (test method EN 1609 and EN 13472). PAROC stone wool does not absorb water and does not increase the risk of damage due to moisture.

When the water absorption is declared, it is shown in the designation code like this: WS1.

When a mineral wool product is used in an application where it is exposed to compression e.g. tank roofs, you need to know the compressive stress capacity. The compressive stress shall be determined in accordance with EN 826. It is declared at the maximum compression of 10% and with the unit of kPa.

Paroc declares the compressive stress for special products, such as roof slabs for tanks.

An example of the compressive stress shown in the designation code: CS(10)80

(the compressive stress to deform the product 10 % of its thickness is over 80 kPa)

Water vapour diffusion resistance is tested in accordance with EN 12086 for flat products and EN 13469 for pipe sections and declared as level MV1 or MV2.

Level	Requirement
MV 1	100
MV 2	200

Water vapour diffusion equivalent air layer thickness.

PAROC stone wool has an open cell structure and does not affect the movement of water vapour. When water vapour resistance is needed, PAROC products with AluCoat® should be used. The AluCoat® facing is class MV2 and it provides the needed vapour barrier and works very well for cold pipes or ducts or other applications where water vapour resistance is required. For these applications, all joints need to be taped with suitable aluminium tape.

Test method EN 13468 is used to determine the level of ions and pH, which must be at the right level. Water soluble ions (or the wrong pH-value) can promote unwanted oxidation or corrosion. In some applications, especially in industry (e.g. at nuclear plants), this might be very important. PAROC stone wool is chemically inert and does not contribute to the oxidation process.

The ions that can be declared are water-soluble chloride (CL), fluoride (F), silicate (SI) and sodium (NA), and declared as mg/kg. For chlorides and fluorides, no test result shall exceed the declared value. For silicate and sodium, no test result shall be below the declared value. The pH-value shall not deviate from the declared level by more than 1.0. The most important factor is the chloride value of the product, which in many industrial plants is required to be less than 10 ppm.

When trace quantities of water soluble ions, for example, chloride and the pH value are declared, it is shown in the designation code like this: CL10 or pH10.

PAROC stone wool is a good sound absorption material due to its open structure. The sound absorption coefficient is tested and declared in accordance with EN ISO 354 and the sound absorption characteristics calculated according to EN ISO 11654.

An EC Certificate of conformity is established by a third party, a notified body. The notified body checks that the manufacturer (e.g. Paroc) fulfils the declared values for each product. The minimum requirement to include in the EC Certificate of Conformity is reaction to fire class and Thermal conductivity.

Paroc has taken this one step further and has certified even more properties than required. This way it is guaranteed by a third party that we keep our promises and it is easy to see that we do so. For Paroc, Technical Research Centre of Finland (VTT) is the notified body.

The key document for CE marking is the EC Declaration of Conformity. This is the document that should always be available for you. In the declaration we as a manufacturer declare that all products conform to and fulfil what we promise. The declaration also states values for that specific product.

For all our CE marked products you will find the EC Declaration of Conformity on our website on product pages.

The EC Declaration of Conformity and the label on the package shall include the information of the manufacturer, the fire class and the thermal resistance or conductivity of the product. It shall also refer to which standard it has been assessed and include all other properties the manufactured needs or wants to declare. This declaration is given by a designation code on the label together with the CE-mark.

The designation code is a string of the declared properties for a product. In this, you can find what properties the manufacturer is declaring.

MW EN 14303 – T2 – ST(+)650 – CS(10)20 – WS1 – MV2 – CL10 – pH9,5

The explanation of the designation code is given in the relevant product standard, in this case EN 14303. The code starts with MW which means Mineral Wool followed by the standard EN 14303. The following abbreviations in the example are explained in the text above.