health, comfort and financial conditions for all with the installation
of thermal insulation.
In assessing the environmental characteristics of insulation
materials, consideration must be given to a broad range of issues
relating to the resources going into their production, manufacturing
processes, pollutants given off during their lifecycle, durability,
recyclability, and impact on indoor air quality. Recycled content
is the most recognized environmental feature of building products.
Materials with recycled content
have four advantages:
1) they require less natural resource;
2) they divert materials from the solid waste stream;
3) creating additional job opportunities for the unemployed by collecting
4) they use less energy during manufacturing.
The insulation industry is full
of good examples of recycled material use:
Cellulose Fiber uses recycled newspaper by weight; the rest is comprised
of fire retardant chemicals and—in some products—acrylic
• Fiberglass uses recycled glass
• Mineral wool actually refers to two different materials:
slag wool and rock wool. Slag wool is produced primarily from iron
ore blast furnace slag, an industrial waste product and Rock wool
is produced from natural rocks.
• Polyester Fiber uses recycled PET bottles
• Polystyrene uses recycled plastic resin in some extruded
and expanded polystyrene.
All South African thermal insulation products are to
comply with National Standards and have to be tested in accordance
with SANS 428:2007 “Fire performance classification of thermal
insulated building envelope systems”, prior to being sold.
Standard incorporates all factors required for fire-hazard or fire-risk
assessment of the materials, or assemblies under actual fire conditions.
any insulation, insulating panel or lining used as thermal insulation
system under an external covering as part of a roof or wall assembly
(thermal insulated building envelope), tested in accordance with
SANS 10177-5 and found to be combustible, shall be acceptable if
it complies with the requirements of SANS 428 when tested in accordance
with SANS 10177-10 for classification and such classification have
been confirmed in accordance with SANS 10177-11 with regard to use
The requirements contained in SANS 428 are intended to evaluate
the fire safety performance of thermal insulated building envelopes.
The test protocol makes provision for both horizontal and vertical
applications and with or without the use of a fixed water extinguishment
Resistance = R-Value
All insulation materials are rated for their performance
in restricting heat transfer. This is expressed as the R value, also
known as thermal resistance. The R value is a guide to its performance
as an insulator—the higher the R value, the better insulation
(i.e., resistance to heat flow) it provides.
are expressed using the metric units m².K/W, where:
refers to one metre squared of the material of a specified thickness;
refers to a one degree temperature difference (Kelvin or Celsius)
across the material;
refers to the amount of heat flow across the material in watts.
the nominal R-values as listed by the manufacturer on the packaging
of the insulation to determine the performance.
which have the same R value will provide exactly the same insulating
effect as each other, provided they are correctly installed.