A group of architects says a simple change to planning rules would allow for up to 20 more apartments to be built on mid-rise projects without any loss of amenity, and it amounts to this: lose the wedding cake look.

Setbacks, which are often imposed by councils to increase stability and privacy, or reduce fire risk, visual bulk and shadowing, taper buildings towards their top, but increase construction costs, carbon emissions and reduce housing supply, four leading architects say.