Office S&M's "two-faced" Janus House extension is coated with spray-on rubber

Spray-on rubber originally developed for oil rigs coats this London house extension by Office S&M, which features both round and rectangular windows.
The studio headed by architects Catrina Stewart and Hugh McEwen designed the structure to provide a new bathroom and kitchen for a property in Walthamstow, replacing a poorly built lean-to extension that was there before.The simple volume is designed to relate in scale to the 19th-century house, but is more modern