Rehabilitasyon Maliyetini Etkileyen Faktörler Üzerine Bir Araştırma

Abstract

Bu çalışmada, özel sektör tarafından rehabilitasyonu yapılmış projelere ilişkin süre ve keşif farkını oluşturan bileşenlerin analizlerinden elde edilecek bulgularla, rehabilitasyon maliyeti tahmininde bir veri tabanı oluşturmak ve daha gerçekçi tahminler yapabilmek, varolan bina potansiyelini değerlendirmede bir ölçü oluşturmak amaçlanmıştır. Birinci bölümde, rehabilitasyona ilişkin temel kavramlar ve rehabilitasyon projelerinin özellikleri anlatılmıştır, İkinci bölümde ise, rehabilitasyon maliyeti kavramından, maliyeti oluşturan unsurlardan, rehabilitasyon maliyet tahmini ve tahmine yönelik yaklaşımlardan bahsedilmiştir. Üçüncü bölümde, diğer bölümlerin sentezi ile beraber, verilerin istatistiksel çözümlemelerinden elde edilen bulgular incelenerek, değerlendirmeler yapılmış ve sonuçlar analiz edilmiştir.

Building rehabilitation has social, cultural and economic advantages. Social, in that people and cities keep their identity; cultural, in that artistic, architectural, and documentary values can be preserved both for their intrinsic value and their contribution to the identity of the city; economic, in that existing capital is used energy is saved, demolition costs af e avoided, and the existing infrastructure of services is utilized. [1] Rehabilitation constituted about 30 % of building production and it is the growth sector within construction; its share is estimated to be almost 35 % by the end of the century. As the share of rehabilitation grows, the decision makers in public administration and in business are going to need ever more information on the long and short term developments in the total quantity of rehabilitation works. [5] Scheduled rehabilitation works should mediate between these two objectives: to perform the best allocation of economis resources and to minimize physical consistence alteration without any distinction between parts or layers imposed by aesthetic or historical criteria and avoiding any replacement of parts components or materials. The new use should involve the minumum change, as this will preserve the values in the building and tend to reduce costs, so the closer the new use is to the original the better, generally. It is true that lack of traditional skills and bad site management by builders without the flexible organization that is necessary can inflate the cost. fX The real cost depends on the structural conditions of building, the proposed use, the skill of the architect in devising plans and the most suitable contract procedures and the skill and organization of the builders. [1] In this study, information on the final cost of a representative sample of dwelling buildings is analyzed. The aim of this study is to analyze the factors influencing the final cost and appreciate the results eventually, provide data on the rehabilitation projects. When we go over the section; 1-Rehabilitation Projects In this section, terminology which is concerned with rehabilitation will be constituted and properties of rehabilitation projects will be mentioned. 2-The Rehabilitation Cost In this section the concept of rehabilitation cost, the cost estimation on rehabilitation projects and components forming rehabilitation cost will be mentioned and the researchs which has been done on it will be explained as follows; i. Construction of indices for building maintenance and cleaning expenditure. The object of this paper is to describe the method used to derive and the input materials used to update the EUCIS Occupancy Costs indices. The indices have been prepared primarily for adjusting the relevant sections of the BMCIS Occupancy Costs analysis. The series consists of redecorations, fabric maintenance, services maintenance and cleaning. [73 ii. Building conversion This paper decribes a system for the prediction of capital cost of building conversion projects. [4] iii. Estimation of the rehabilitation cost for housing buildings. This paper presents a method of rehabilitation cost estimation for housing buildings, particularly fit for application in Lisbon. [81 Furthermore, as a result of the research on literature and on projects rehabilitated by private sector to obtain data on rehabilitation, the factors influencing the final cost was identified as follows: i.The factors relating to project -Age of dwelling -Construction system -Gross construction area -Number of floor -Height of floor -Building form -Conditions of use -State of installation -Number of user -Finishing level of project ii. The factors relating to cost and duration The factors relating to duration -Planned duration -Real duration -Time extention -Delay XI The factors relating to cost -Contract price -Cost per m2 -The second estimated cost -Final cost -Price drift (Price drift-contract price/contract price) -Variations -Factors forming the price drift The price drift was expressed as follows; D = A-S = F+V+P+C D = The price drift  = The final cost S = The Contract price V = Variations (variations on design after contract) P = Variations (variations on items) C = Claims iii. The factors relating to management -Contract form -Price form -Project form -Adjudication form -Encouragement, penalty and sanctions on contract -Experience level of construction form XII -Conflicts on contracts -Plannig and controling -interferences on projects. 3-The Respective Of The Research In this section, collecting data and formation of the sample will be explained, measuring variables and the analysis to describe them, establish the relationships between them and obtain a model on the rehabilitation cost, will be mentioned. As a result of analysis which was used to describe the variables, mean, minimum, maximum and standart deviation values of variables were identified for interval variables and frequencies for nominal variables. Correlation was u^sed to measure the relationships between variables. The Mann-Whitney U Test analyzed the hypothesis that two independent samples come from population having the same distribution and Kruskal Wallis One Way Analysis Of Variance tested the same thing with The Mann-Whitney Test for more than two independent samples. Multiple linear regression (MLR) analysis was the most suitable technigue to establish the relationships between variables. A Backward Elimination algorithm of the multiple linear regression available in the Statistical Package for the Social Sciences (SPSS) was used to obtain a model on the rehabilitation cost. Using MLR the equation was obtained as follow; Ymodel = 39.09 * XI + 143.72 * X2 - 505.20 * X3 (1) XI : Gross construction area X2 : Age of dwelling X3 : Number of user XIII Using regression analysis to establish the relationship between observed cost (The final cost) and expected cost (Ymodel) the equation was obtained as follow; Yoc =.69 * Ymodel (2) In this study, the factors influencing the final cost were analyzed, the results were appreciated and obtained a model on the rehabilitation cost. The results will be useful to researchs corcerned with rehabilitation.