A worker’s cottage on an inner-city suburb in south Australia gets a major upgrade for a growing family. The existing front four rooms are retained with the cramped lean-to and extension removed to make way for a new addition containing a new kitchen/dining and living, new bedroom and wet areas, and a second living/ kid’s area on the upper-floor level. The new addition is pushed to the south/west of the site, allowing north light into the new kitchen/living with a ‘twist’ to the box to help the orientation. A double-height void over the dining works to passively heat and cool the space without reverse-cycle AC, venting out hot air in summer and bringing winter sun deep into the floor area to heat the concrete slab.