Why is smart decentralised HRV not yet common practice in large renovation projects?

Practice is largely built around familiar system types, standard specifications, fixed responsibilities and cost estimates. As a result, larger projects often start from a central system or from existing ventilation patterns by default. In addition, smart decentralised solutions have been known to many stakeholders for a shorter time and require a different design dialogue: not just ‘how much air does the home need?’, but also ‘which room needs which air quality, and when?’. Unfamiliarity is not a technical counter-argument, but it is a real barrier to specification and tendering.