There are two types of preventive maintenance:

I. Scheduled Periodic Maintenance

Scheduled periodic maintenance is carried out in accordance with systematic data monitoring and analyses, which enable the owners to gain a thorough understanding of information regarding each element of the building (including life expectancy, depreciation rate and actual deterioration) for a comprehensive, thorough and practical maintenance scheme to be formulated. Upon completion of the survey, the required maintenance or replacement will be carried out as scheduled in the maintenance cycle. Notwithstanding the condition of the element concerned, maintenance works will be carried out as planned to prevent foreseeable failure or damages so as to ensure good condition of the building in the long run.

This maintenance approach, implemented only with an effective management system, is more common in commercial buildings and public facilities than in residential buildings as owners and Owners’ Corporations (OCs) of the latter lack the data and information necessary for the formulation of an applicable maintenance scheme, let alone the management system that governs it.

II. Monitored Periodic Maintenance

Operated in a similar fashion to the scheduled approach, monitored periodic maintenance differs in the way that, before the maintenance or replacement, assessments and analyses will be carried out on each element of the building for the compilation of a list of works to be included in the project, with a view to ensuring the conditions of the elements concerned are maintained at a reasonable level within the cycle.

In the case of common residential buildings where the expected standards of operation are not as high as commercial buildings and public facilities, this approach helps strike a balance between cost and proper maintenance.