This is relevant to existing buildings that do not work effectively or economically for whatever reason. This can and often does include mistakes in the original design, poor installation, poor record documentation, inadequate commissioning and testing (most of this driven by value engineering) and possibly poor maintenance.
The net result is that there is no shortage of reasons why building services might not perform as well as they should. The most frequent outcomes are dissatisfaction with the performance of the air-conditioning and increased operating costs.
The solution is to carry out a forensic survey of the installations, usually with particular attention paid to the controls, to at least determine the root causes of problems. This would be conveyed to the client in a detailed report with recommendations as appropriate.ITF Consulting