The retrofit movement faces barriers, primarily high costs, but is crucial for reducing operational energy and carbon emissions. 

With more demanding energy targets ahead, the focus must shift from short-term completion goals to long-term energy efficiency. 

Early investment in systems like HVAC and lighting can yield future benefits, including higher energy performance ratings. 

A holistic approach, considering the building's end-use, energy needs, and tenant requirements, is vital for effective retrofitting. 

Both active (e.g., heat pumps) and passive (e.g., insulation) solutions must be weighed carefully, balancing cost, space, and energy demands.

Successful retrofits will future-proof assets, enhancing sustainability and value.