Background/purposeDespite its severity not much work has been done to explore the barrier function in patients with erythroderma. This study compares TEWL between skin of healthy subjects and erythrodermic patients of various aetiologies and at different sites. We also assess TEWL between patients with acute and chronic erythroderma.MethodsTwenty‐five erythrodermic patients and 26 age, race and sex‐matched healthy controls were recruited. TEWL measurements were performed at five sites; right cheek, left volar forearm, abdomen, upper back and right calf using Tewameter TM 210.ResultsTEWL in erythrodermic patients were significantly higher than healthy individuals at all the sites (P < 0.001). There were significant differences in TEWL between different anatomical sites in controls (P < 0.001) but not in patients. The highest TEWL for the patient and control groups were that of the abdomen and the right cheek respectively. Acute erythrodermic patients (n = 9) seemed to have a higher TEWL than chronic erythrodermic patients (n = 16) although the differences were not statistically significant. There was no significant difference in TEWL among erythrodermic patients of various aetiologies.ConclusionErythrodermic skin regardless of aetiology has much higher TEWL compared to normal skin. Differences in TEWL among various anatomical sites observed in normal skin were not seen in erythroderma.