Composite insulation products are becoming more popular as they fulfil multiple roles. Typically these products are a layer of foam (or other insulation material) sandwiched between two layers of aluminium foil. They are manufactured in rolls and often as a specific underfloor insulation roll with a width of 500mm.
These products can also be useful in retrofitting insulation in walls. As they are semi rigid, a single weatherboard can be removed from the external cladding of the home and the material threaded down the cavity to the floor level. See THIS ARTICLE for a discussion on retrofitting walls with E-therm.
Typical of these products are:
Kingspan Air-cell Permifloor and Permifloor 500 . This product is available through K&D Mitre 10
Thermotec E-therm is available in various thicknesses but generally the thickest 8 mm product is most useful in Tasmania. Available
Another composite insulation type commonly used is FoilBoard.
Becks Home Hardware
Becks Pty Ltd
30 Patriarch Drv, Huntingfield TAS 7055
ph: (03) 6229 1148
Stocks some products, but can order what is required. The Fibregalss Shop in Hobart may also sell some products, but planning to get out of this line.