Building maintenance priority assessment for building components

The aim of the research was to identify the building structure components that needed to be fixed first according to the priority assessment. The object of the research was traditional market buildings in West Jakarta managed by PD Pasar Jaya. The research was conducted through a survey, sending out questionnaires, and conducting interviews with experts. Building components were analysed using relative importance index to identify the most important building components to be maintained. Out of 135 building components there are 32 building components which are identified to be important. Through analytical hierarchy process (AHP), 9 building components need to be mitigated to avoid further damage to the traditional market building.


Introduction
The growth of modern market in Indonesia has increased up to 31,4% per year while the traditional market decreases to 8% per year. The Indonesian Market Traders' Association recorded up to 400 traditional market closes every year across the country. In Jakarta, one of the Governor's work program in the Provincial Regulation of the Special Capital Region of Jakarta No. 3 of 2009 concerning Management of Market Area, every traditional market in Jakarta have to be maintained to keep the value of benefits and function of the market. However, several issues arise such as limited human resources and funds in the maintenance of traditional market [1]. Other research shows that leakage is seen as the most common issue in buildings in general. This is mainly caused by the insufficient technical staff to cover a vast area of building, the unawareness of building occupants' and availability of maintenance budget [2]. A condition assessment needs to be the base on decision making in maintenance management the development of sustainable construction [3]. To better distribute financial resources throughout the needs for building maintenance, maintenance calls are based on monthly demand, building lot and nature of the service requested [4]. Therefore, a priority assessment of building components needs to be done in building maintenance. The goal of this research is a prioritized list of building sub-elements that are frequently experiencing damage with a proposed mitigation solution.

Building maintenance and treatment
Building maintenance and treatment are two different activities. Building maintenance are all the activities to ensure the reliability of the building and its facilities to function well. Whereas building treatment are all the activities to repair and/or replace building components, building material, and/or 2 building facility to maintain the feasibility of the building [5]. There are several problems arises in building treatments in Indonesia. The level of damage and deterioration of quality of the building material, the level of building management services, the level of building occupants' involvement and the level of maintenance budget availability are some of the factors influencing the condition of buildings in Indonesia [2]. Other factors are faults during construction stage, unavailability of as built drawing, changes in the function of the building, unavailability of historical data on building utilities, unavailability of spare parts and no technical guidelines for building maintenance and treatment [5].

Methodology
The object of the research were traditional market buildings in West Jakarta managed by PD Pasar Jaya. Data were achieved through surveys, sending out questionnaires and conducting interviews with experts. Twenty-four traditional market buildings located in West Jakarta, only 16 were qualified as the object of this research. The 16 traditional market buildings were chosen based on the location of the market. Some traditional markets were not based on a permanent building, rather than they were based on the pedestrian which is a temporary placing. Only traditional market which was placed in a building that was chosen to be the object of the research. Surveys were conducted to the 16 buildings to identify the components, elements and sub-elements of building structure associated with traditional market building.
Questionnaire were conducted in 2 stages. The 1 st stage of questionnaires was conducted to identify the importance index of each building sub-elements which is usually worn down in a traditional market building using the relative importance index method. The building sub-elements identified in the 1 st stage questionnaire is used in the 2 nd stage of questionnaire to identify the priority list of the important building sub-elements that needs to be mitigated, that is analyzed through analytical hierarchy process (AHP). Mitigation solutions were later proposed through a series of interviews with experts to analyze even further regarding the impact, the cause, the preventive solution, and the corrective solution for the building sub-elements.

Relative importance index (I)
The relative importance index (I) analyses the frequency of an event occurring using the formula (1). The event in the research is the damages that occur on the building components of a traditional market building. (1) The value of i can be seen in Table 1. The result of I is then plotted using Table 3 to categorise its scale [6].

Analytical hierarchy process (AHP)
The research uses AHP to analyse the priority degree in building maintenance of the building subelement achieve from the relative importance index analysis. This method was introduced by Saaty by using pairwise comparisons [7]. AHP can solve multi object and multi criteria problem based on the preference comparison for each element in the hierarchy. The use of AHP needs to weigh each element to later be analyzed in pairwise comparison against each element, constructing a hierarchical structure between elements and calculating a consistency ratio [8]. The illustration of the AHP hierarchy modelling structure for this research can be seen in Figure 1.

Results and discussion
Through literature studies, 163 sub-elements were obtained that were associated with buildings in general which often experience damages. However only 135 sub-elements were associated with traditional market building. These sub-elements were obtained from the surveys conducted to the 16 traditional market buildings in West Jakarta. On the 1 st questionnaire, questionnaires were given out to 16 traditional market buildings in West Jakarta to achieve the relative importance index of sub-elements of the building based on the frequency of damage using the Likert Scale. Seven sub-elements were categorized as "very important" and 25 subelements were categorized as "important" based on the scale in Table 3. Only these 32 sub-elements were used in the next stage to be prioritised as it is seen to be the most important element in the building.
On the 2 nd questionnaire, structured interviews using the Saaty scale were given out to 3 experts that specializes on the building maintenance and treatment. The Saaty scale defines a quantitative scale from 1 to 9 to assess the comparison of the importance of one element to other elements. A scale from 1 to 9 is said to be the best scale to qualify an opinion. Therefore 9 categories are given, whereas each of the categories have different intensity of interest [9].
Using the analytical hierarchy process (AHP) the 32 sub-elements retrieve from the 1 st questionnaire is then prioritised. The priority ranking from the AHP analysis can be seen in Table 4. It can be seen from Table 4 that damages in tile or roof cover makes the top priority to be mitigated compared to the damages/flaws in ceiling paint.

Table 4. Priority Ranking of Sub-Elements of Traditional Market Component
In determining the critical sub-elements, data of potentially damage sub-elements is needed. Those data can be achieved through critical analysis approach [10] which is categorized in 4 criteria: high damage frequency, the impact damage to the system, difficulty in disassembling and assembling and expensive price of the components.
The priority ranking on Table 4 was then validated back to the 3 experts and another deep interview were conducted to narrow down the priority list and to analyse the impact, the cause, the preventive measure, and the corrective action for damages occurring in the building sub-elements. There are 4 categories in prioritizing the sub-elements in building maintenance. It is based on operational, safety, supply and disposal, and security [11]. Based on the 4 categories the 32 sub-elements were narrowed down to 9 prioritised sub-elements those are critical in building maintenance and treatment of a traditional market building. The 9 sub-elements and the mitigation solutions can be seen in Table 5.

Sub-elements
Water supply system, power supply system and fire protection system were also listed as the utilities that require routine maintenance to enhance the performance of the maintenance tasks [12].

Conclusion
Based on the analysis, it can be concluded that there are 9 critical sub-elements that needs to be prioritised in the building maintenance and treatment of a traditional market building. Those 9 subelements are tile or roof cover, fire extinguisher, water pump, tap water, switch, fitting, lamp, electric socket, and rainwater gutter.
The 1 st priority is the tile or roof cover to ensure that all the activities in a traditional market building are still operational [13] & [14]. The 2 nd priority that needed to be prioritised is safety. Therefore the availability of fire extinguisher is critical in a building as it is the main indicator for a building reliability requirement to be able to overcome fire hazard [11].
The later priority is supply and disposal. This indicator is split into 2 categories, the supply of electricity and the supply of water, which is related to sub-elements water pump, tap water, switch, fitting, lamp, electric socket and rainwater gutter. Damages related to roof leakage and electricity and water installation have a high impact on the tenants' activities and can impact other sub-elements when not fixed immediately [15].
The scope of the research is only to identify and priorities building components that frequently experiencing damages and proposed a mitigation solution. Most of the buildings in Indonesia still uses corrective strategy as the building maintenance strategy. Based on the result, a maintenance scheduling for building maintenance in traditional market building can be analysed and proposed. This can minimize further damage to the building components as the life span of each building components has been accounted for. This strategy refers to as a preventive building maintenance strategy, which is a more effective maintenance strategy to ensure the constant and efficient usage of building systems and their components [16]. Routine maintenance is said to be able to support intended function of building components and retain its value [12]. Building maintenance must not only focus on the present condition but also calculate the expected decay rates for the years to come [17].