The Advertising Standards Authority has upheld a complaint against an insulation maker that claimed its thermo-reflective insulation was as effective as traditional insulation.

Actis claimed that its Tri-Iso Super 9 product, which is 25mm thick and consisted of layers of reflective foil separated by wadding, had a thermal performance equivalent to 200mm of mineral wool insulation.

The ASA examined the test methods used and concluded Actis “had not substantiated the claim”.

Actis said its publicity was based on tests on real buildings, as laboratory tests measured heat transfer principally by conduction rather than reflection.

But the ASA found that two identical chalets, built for the test in France in 1997 were not typical of normal building practice, as neither had been constructed with a tiling underlay or plasterboard lining.

Actis claimed the use of plasterboard and underlay “was not common in France in 1997”.

Tri-Iso Super 9 has since been discontinued and replaced by Tri-Iso Super 10.