This method of test described a means of determining the thermal resistance of textiles articles which may be filled e.g. padded coats and jackets, child sleep bags, cot duvets, etc., or textiles articles with a thermal resistance of up to 0,5 m2K/W (5,0 tog) and/or which do not have uniform thickness. The test method is suitable for products with a thermal resistance within the range 0,025 m2K/W (0,25 tog) to approximately 0,5 m2K/W (5,0 tog) but is limited only by the ability of the test apparatus to cope with the thickness of the test sample.