The ratio of changes in construction costs and development index of the standard analysis of construction costs for state buildings

Abstract

Wages rate and material price are an important part of a construction cost. The Construction Cost Index (CCI) that has been developed which applies to a certain area or period a basis for determining the bid price. This index is also very useful to forecasting construction cost which should reflect the comparison of wages rate and material price changes over time. Standard Construction Cost Analysis per m2 is one of the performance budget instruments to assess the budget of a construction project. Surabaya City Government applies that standard in set up government budget. SCC is composed of several Unit Price Analysis with a certain volume that design has been standardized. The composition of the labour and material price index, as a cost driver for Standar Construction Cost Analysis based on time units are expected to be used in the preparative of cost estimates for Building Construction and further research related to the effect of price increases on construction costs. The results obtained from this study are the construction cost change ratio in Surabaya for 2013-2016 increased average 17.3% per year; start from 2016 - 2020 increased not over 6,5% per year. Where as material cost change ratio tends to increase every year, except for 2014 - 2015 which has increase dramatically. In the other hand the labour price index indicate a constant increase because it was related to the Surabaya City Minimum Wage Rates, but in the early year in data (2013-2014) the Minimum Wage Rates significantly increased. In 2017-2018 labour cost change ratio increased more higher and material cost change ratio turn to decreased because the analysis used new guidelines for Analysis of Work Unit Prices for Public Works (Regulation of the Minister of Public Works and Public Housing of the Republic of Indonesia number 28 / PRT / M / 2016). The average component weight of the CCI according to the development of price are labour and foreman (41,3%), stone / brick (10,7%), roof truss and cover (10,4%), cement (8%), floor cover and paint (7,4%), wood (6,8%), iron bar (5,6%), accessories and complement (5,6%) and sand (4,2%). Material cost index tends to increase every year, except for 2018 and 2019 which has decreased. Whereas labour cost index indicated a constant increase because it was related to the UMK (City Minimum Wage) Surabaya. So that the CCI from 2013 to 2020 has increased from 1,00 to 1,93.