Radiative transfer models have been produced for stars surrounded by circumstellar dust shells in order to investigate the detectability of the 11.5-µm librational band due to water-ice (H 2 Oice). The dust grains were assumed to be composed of a core material of either amorphous silicate of olivine composition (MgFeSiO 4 ) or alumina (Al 2 O 3 ), both grain species being coated with a water-ice mantle. The models may be divided into three classes: those with small, intermediate and large optical depths. It is found that in all three cases, even with only olivine present, the water-ice librational band feature is masked by radiative transfer effects and is therefore difficult to detect.For the librational band to display its characteristic shape requires far larger amounts of water-ice than are present in any known circumstellar dust shell, as indicated by the depth of the much stronger 3.1-µm water-ice band. The best prospect for finding some evidence of the librational band is likely to be via using a small beam centred on the cooler outer regions of the dust shell; in this case the line of sight may encounter only water-ice coated grains, thereby reducing the contaminating effect of bare grains. If a grain species such as alumina is present, with a broad absorption band in the vicinity of 11.5 µm, the identification of the librational band may be possible, perhaps surprisingly, as result of the sharpening of the 11.5-µm feature. We have fitted the spectrum of IRAS 22036+5306 and find that, although water-ice is clearly present in this object, as evidenced by the presence of the strong 3.1-µm band, the librational band has no obvious effect on its 10-µm spectrum.