The technique of real‐time holographic interferometry is used in the present study to study natural convection in a fully‐partitioned air‐filled square enclosure. Transient and steady‐state temperature distributions in separated subenclosures are visualized for a Rayleigh number between 2.5×105and 8.4×105with a centrally‐located conducting partitions. Steady‐state experimental results are found to be in reasonably good agreement with the numerical predictions. Moreover, the experimental observations during the transient one‐sided heating processes indicate that the presence of a conducting partition can provide a good buffer against a sudden external disturbance to the enclosure.