The Spool CpA #6 issue on Human-Robot Interaction for Carbon-free Architecture reviews current tendencies in autonomous construction and human-robotic interaction in architecture. It aims at affirming and/or challenging research agendas in the domain of architectural robots and attempts to answer questions about (i) the fundamental framing of post-carbon autonomous construction, (ii) the interdependencies between machines, humans, and materials, and (iii) the different imple-mentation timeframes ranging from continuous transformation to leapfrogging.@en