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In the present work, flat and micro-/nano-rough water and ice-repellent coatings based on room-temperature vulcanized silicone rubber (RTV SR) incorporated with titania (TiO2) nanopowder as a dopant were prepared and investigated. Such water and ice-repellent coatings are potential candidates for protecting high-voltage equipment such as conductors and insulators. Supehydrophobic samples with contact angle (CA) >145 o and contact angle hysteresis (CAH) ~5-10 o were prepared by spin coating TiO2-loaded RTV SR suspensions on etched substrates. The SEM investigations of the sample surfaces revealed that the alumina filler (loaded into the as-supplied silicone rubber product) had some influence on the surface topographies of the prepared coatings. It was also found that the nanopowders used as dopants further increased the surface roughness (and correspondinglywater repellency) of the coatings. While the TiO2-doped RTV SR demonstrates high CA and low CAH values, which is characteristic of the Cassie wetting regime, the wetting mode on the rough RTV SR coated sample with high CAH is expected to be a mixed Cassie-Wenzel regime. The anti-icing behaviour of the coating was studied under atmospheric icing conditions. Rough superhydrophobic coatings prepared with TiO2 nanoparticles of dielectric constant (~80) resulted in reducing the ice adhesion strength by at least ~7 times compared to a mirror-polished aluminium sample and by ~9 times compared to an as-received aluminium sample. At approximately-15 o C, water droplets were found to freeze on polished aluminium after approximately 5 s, while their freezing was delayed by as long as ~12-13 min on a superhydrophobic nanocomposite surface doped with TiO2 powder. This delay is explained by the insulating properties of the rough surface that entraps a significant amount of air into its structure. Therefore, the coatings prepared show promise for industrial applications on high-voltage equipment, including insulators, since they can reduce ice accumulation, while also reducing the risk of flashover on outdoor insulators.