Thermtek is a revelation. It is Parkwood's unique thermally broken technology in aluminium. Cold is kept outside, and warmth inside by enhancing the thermal properties of an aluminium door.
This is done using a rubber clip system that almost completely separates the inside face of the door from the outside face, thereby stopping the transmission of heat/cold. Other benefits are high sound travel reduction (quieter inside the home) and reduced condensation on the door.
Finally, they have a lovely feel of solid quality, not found with other aluminium doors on the market, but something so badly needed with the main entry door to a home. First impressions count!