Page 5 - BREDI-S-Sliding thermal break system
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BREDI® window/door systems deliver many advantages, most
importantly improved thermal performance. The advantages
of aluminium are maintained - such as strength, durability and
stability-yet the drawback of thermal conductivity is
overcome. This makes BREDI® windows/doors an ideal
solution for commercial building applications and high-end
residential projects where large, complex glazing solutions are
required.
how does it work?
BREDI® windows/doors improve energy efficiency by
controlling the forms of heat transfer. Heat or thermal heat
energy can be transferred through a material in three
manners:
Conduction is simply the process where heat is transferred
through materials that touch one another.
Convection is where gasses or liquids circulate to transfer
thermal energy.
Radiation transfers heat energy at a distance through high frequency waves such as visible light,
ultraviolet light or microwaves
BREDI® window/door frames are insulated against heat and cold conduction. This is done by
separating the outside metal parts from the inside with a material which reduces the amount of
heat or cold transferred through the frames. This feature is known as the “thermal break”.
A thermal break is a non-metallic resin or plastic material installed in the metallic window frame
that physically separates the interior part of the window from the exterior part. Hence the
pathway for heat energy to be transferred or conducted through the window frame is “thermally
broken” The formal denition from the National Fenestration Rating Council (NFRC) is as
follows:
Thermal break: a material of low thermal conductivity that is inserted between members of high
conductivity in order to reduce heat transfer. Thermal barrier material conductivity shall be no
more than 0.5 W/m.K.
BREDI® window/door can be described as one in which the frame and sash components
(members) have been split into interior and exterior elements and joined using a less conductive
material. The formal denition of a thermally broken “Member” from the National Fenestration
Rating Council (NFRC) is as follows:
Thermally broken (TB) members: system members with a minimum of 5.30mm separation
provided by a low-conductance material (where thermal conductivity (is) less than or equal to 0.5
W/m.K or open air space between the interior and exterior surfaces. Such systems include
members with exposed interior or exterior trim attached with clips and all skip/debridged
systems.
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