FGIA - Thermal Barriers | Aluminum Material Council

Thermal barriers are made from resins that create a “thermal break” between the inner and outer surfaces of aluminum fenestrations.
Thermal barriers reduce heat loss or heat gain through the aluminum.
Thermal barriers improve the U-value characteristics of finished systems.
Thermal barriers are about energy conservation, U-values and government codes
70 percent of aluminum fenestration systems produced in North America contain a thermal break

Primarily used in colder climates to reduce heat loss
Increasing use of thermal barriers to reduce heat gain and also reduce heat loss
Developers, architects and designers are demanding better performance in terms of power usage
Stricter government regulations to reduce power usage in buildings to combat environmental concerns
Aluminum, if it is to retain its market superiority in terms of its structural integrity, will have to achieve better performance in terms of U-values
The use of thermal barriers will assist manufacturers to achieve improved LEED performance

Currently, there are two principal types of thermal barriers used in North America: polyamide thermal barrier strip and pour & debridge (P&D).

Pre-extruded profiles made from polyamide with 25 percent glass-fiber
Locked in place in “pockets” extruded into two separate (inner and outer) aluminum extrusions
Enables finished assemblies with different finishes and colors on each surface
Aluminum extrusion pockets need to be “knurled” prior to insertion of the polyamide profiles – and “rolled” to create a structurally-secure finished assembly
The polyamide profiles can be supplied with ”sealing-wire” which give a reliable seal and enhanced shear strength when activated by heat e.g. – powder-coating
The aluminum extrusions can be finished either before or after installation of the polyamide strips

P&D is the most widely used system for thermal barriers in North America
It is a polyurethane-based system
An Iso is mixed with a resin at the point of assembly and the mixture is poured into a barrier channel in the aluminum extrusion
After pouring and curing, the barrier channel is “debridged”
The debridging process creates the separation between the inner and outer surfaces
A mechanical locking system on the extrusion is recommended to eliminate possible problems with dry shrinkage