Roxul Industrial Insulation Process - Manual (Page 39)

1.2.5 Cladding
Suitable cladding should be applied to protect the
insulation from weather influences, mechanical loads
and (potentially corrosive) pollution. Selecting the
appropriate cladding depends on various factors, such
as working loads, foot traffic, wind and snow
accumulations, ambient temperatures and conditions.
Note
An insulation system resistant to foot traffic
must not become permanently damaged if a
person weighing 220 lbs (100 kg), (weight
including any tools being carried) walks
across it. It is not designed to bear additional
loads, such as the placing of heavy equipment.
For the purpose of the safety regulations, a
durable insulation is not considered to be a
walkable surface.
When selecting the appropriate cladding, take the
following points into account:
As a general rule, galvanized steel is used in
buildings due to its mechanical strength, fire
resistance and low surface temperature (in
comparison to an aluminum cladding).
Aluminum is used outdoors, because it is easy
to fit and more cost-effective than stainless
steel and does not tend to corrode under
common weather conditions.
In corrosive environments, aluminized steel,
stainless steel or glass reinforced polyester is
used as cladding. Stainless steel is
recommended for use in environments with a
fire risk.
The surface temperature of the cladding is
influenced by the material type. The following
applies as a general rule: the shinier the
surface, the higher the surface temperature.
To exclude the risk of galvanic corrosion, only
use combinations of metals that do not tend to
corrode due to their electrochemical potentials
(also see page 21 in Chapter 1.1).
For acoustic insulation, a noise absorbent
material (bitumen, mylar foil) is mounted on the
insulation or inside the cladding. To reduce the
risk of fire, limit the surface temperatures of
the cladding to the maximum operating
temperature of the noise absorbent material.
1.2 Insulation of piping
Max. surface temperature
Cladding material Areas at risk
of fire
Corrosive
environment
< 120 °F
(50 °C)
< 140 °F
(60 °C)
> 140 °F
(60 °C)
Aluminum sheet - -
Aluminum/zinc coated steel sheet - -
Galvanized steel sheet -
Austenitic stainless steel sheet
Aluminized steel sheet
Plastic-coated steel or aluminum - -
Glass fiber-reinforced polyester
(e.g. ProRox ® Rocktight)
- < 190 °F (90 °C)
Coatings/mastics - - 175 °F (80 °C)
Foils - -
The thickness of the metal sheet depends on the pipe dameter and the type of the metal.
With special acoustic requirements, a larger thickness [> 0.04" (1 mm)] is generally used.
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