Dowell Thermaline™ windows and doors


  • In choosing a ThermaLine™ window or door you are choosing to lower the likelihood of condensation formation, thereby lowering the risk of dust mite and mould growth.
  • The Dowell ThermaLine™ range has exceptional Air Infiltration performance – an important factor if the conditions inside a home are to be strictly controlled.
  • ThermaLine has market leading thermal performance that can mean significant energy savings in a home
  • Product is 100% recyclable.

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About this brand

Dowell has a history in the fabrication and supply of […]

Dowell ThermaLine™ windows and doors are double glazed, thermally broken aluminium frames. Aluminium is a uniquely strong, lightweight, ductile, corrosion resistant material that can also be recycled. The thermal break technology in TheramLine™ is created using a highly engineered polyamide (plastic) strip that acts as a thermal barrier between the outer and inner aluminium components of the window frame. This minimises the transfer of heat and cold through the window frame, resulting in improved energy efficiency.

All ThermaLine™ products have been independently tested and verified in accordance with the Australian Window Association Windows Energy Rating Scheme (

The following products are Sensitive Choice approved:

  • ThermaLine™ Awning window
  • ThermaLine™ Multi-transom awning window
  • ThermaLine™ Sliding window
  • ThermaLine™ Fixed-light window
  • ThermaLine™ Sliding door