A Model Proposal for Estimate the Approxımate Costs and Contract Fees of Public Education Buildings (School Buildings)

Servet Kesim; Latif Onur Uğur

Article Details

A Model Proposal for Estimate the Approxımate Costs and Contract Fees of Public Education Buildings (School Buildings)

Authors:

Servet Kesim | Latif Onur Uğur

Publisher:

Duzce University

Main Topics:

Yapı İşletmesi

Journal:

Düzce Üniversitesi Bilim ve Teknoloji Dergisi Vol.13 Issue 1, pp.197-218

Document Type:

Article

Publication Date:

1/2025

Document Language:

English

Document ID (Org No.):

2001339869

pISSN:

2148-2446

Keywords:

Abstract:

 In this study, a method is proposed for the preliminary estimation of school building costs. For this purpose, the projects of 96 school buildings, which were put out to tender by public institutions and the result announcement was published, were provided from the Electronic Public Procurement Platform. These projects are divided into 81 training data and 15 test data. The construction cost of educational buildings through projects may affect the output vectors; Number of Classrooms, Construction Duration, Total Number of Floors, Floor Height, Building Height, Building Height Class, Basement Height, Earthquake Design Class, Floor Class, Ground Safety Stress, Bed Coefficient, Concrete Class, Number of Elevators, Wet Area, Raft Foundation Height, Floor Area, Basement Area, Total Area parameters were determined and used in modeling and analysis. Analyzes were carried out with SPSS Statistics 26 software. Using these parameters, Regression Analyzes RA were performed and equations were developed to estimate the costs of educational structures. Approximate Costs and Contract Prices were tried to be estimated with the developed models. The model in which all parameters were used with the created equations was the model with the best correlation level, with the determination coefficient R²0.900 for the Approximate Cost Price and R²0.927 for the Contract Price. An error rate of 17,5 was found between the approximate cost estimates obtained using the model and the actual costs. It was determined that there was an 18,2 error between the estimated contract prices and the actual contract prices. The Durbin-Watson criterion was used to check the consistency between predicted results and actual results. As a result, an approach that can estimate the approximate costs and contract prices of school buildings of different types and coefficients with error rates lower than 20 has been created. Both public institutions and contracting construction companies will be able to make realistic cost estimates by benefiting from these modeling, providing time savings. Conducting similar studies by increasing the number of data may be a solution to minimize the error rate in subsequent modeling.

 In this study, a method is proposed for the preliminary estimation of school building costs. For this purpose, the projects of 96 school buildings, which were put out to tender by public institutions and the result announcement was published, were provided from the Electronic Public Procurement Platform. These projects are divided into 81 training data and 15 test data. The construction cost of educational buildings through projects may affect the output vectors; Number of Classrooms, Construction Duration, Total Number of Floors, Floor Height, Building Height, Building Height Class, Basement Height, Earthquake Design Class, Floor Class, Ground Safety Stress, Bed Coefficient, Concrete Class, Number of Elevators, Wet Area, Raft Foundation Height, Floor Area, Basement Area, Total Area parameters were determined and used in modeling and analysis. Analyzes were carried out with SPSS Statistics 26 software. Using these parameters, Regression Analyzes RA were performed and equations were developed to estimate the costs of educational structures. Approximate Costs and Contract Prices were tried to be estimated with the developed models. The model in which all parameters were used with the created equations was the model with the best correlation level, with the determination coefficient R²0.900 for the Approximate Cost Price and R²0.927 for the Contract Price. An error rate of 17,5 was found between the approximate cost estimates obtained using the model and the actual costs. It was determined that there was an 18,2 error between the estimated contract prices and the actual contract prices. The Durbin-Watson criterion was used to check the consistency between predicted results and actual results. As a result, an approach that can estimate the approximate costs and contract prices of school buildings of different types and coefficients with error rates lower than 20 has been created. Both public institutions and contracting construction companies will be able to make realistic cost estimates by benefiting from these modeling, providing time savings. Conducting similar studies by increasing the number of data may be a solution to minimize the error rate in subsequent modeling.

 In this study, a method is proposed for the preliminary estimation of school building costs. For this purpose, the projects of 96 school buildings, which were put out to tender by public institutions and the result announcement was published, were provided from the Electronic Public Procurement Platform. These projects are divided into 81 training data and 15 test data. The construction cost of educational buildings through projects may affect the output vectors; Number of Classrooms, Construction Duration, Total Number of Floors, Floor Height, Building Height, Building Height Class, Basement Height, Earthquake Design Class, Floor Class, Ground Safety Stress, Bed Coefficient, Concrete Class, Number of Elevators, Wet Area, Raft Foundation Height, Floor Area, Basement Area, Total Area parameters were determined and used in modeling and analysis. Analyzes were carried out with SPSS Statistics 26 software. Using these parameters, Regression Analyzes RA were performed and equations were developed to estimate the costs of educational structures. Approximate Costs and Contract Prices were tried to be estimated with the developed models. The model in which all parameters were used with the created equations was the model with the best correlation level, with the determination coefficient R²0.900 for the Approximate Cost Price and R²0.927 for the Contract Price. An error rate of 17,5 was found between the approximate cost estimates obtained using the model and the actual costs. It was determined that there was an 18,2 error between the estimated contract prices and the actual contract prices. The Durbin-Watson criterion was used to check the consistency between predicted results and actual results. As a result, an approach that can estimate the approximate costs and contract prices of school buildings of different types and coefficients with error rates lower than 20 has been created. Both public institutions and contracting construction companies will be able to make realistic cost estimates by benefiting from these modeling, providing time savings. Conducting similar studies by increasing the number of data may be a solution to minimize the error rate in subsequent modeling.

 Bu çalışmada, okul binası maliyetlerinin ön tahmini için bir yöntem önerisinde bulunulmuştur. Bu amaçla, Kamu Kurumları tarafından ihaleye çıkılmış ve sonuç ilanı yayınlanmış 96 adet okul binasına ait projeler Elektronik Kamu Alımları Platformu EKAPtan sağlanmıştır. Bu projeler 81 adet eğitim, 15 adet test verisi olacak şekilde ayrılmıştır. Projeler üzerinden eğitim yapılarının inşaat maliyeti çıktı vektörlerini etkileyebilecek; Derslik Sayısı, Yapım Süresi, Toplam Kat Sayısı, Kat Yüksekliği, Bina Yüksekliği, Bina Yükseklik Sınıfı BYS, Bodrum Yüksekliği, Deprem Tasarım Sınıfı DTS, Zemin Sınıfı, Zemin Emniyet Gerilmesi, Yatak Katsayısı, Beton Sınıfı, Asansör Sayısı, Islak Alan, Radye Temel Yüksekliği, Kat Alanı, Bodrum Alanı, Toplam Alan parametreleri belirlenerek modelleme ve analizlerde kullanılmıştır. Analizler SPSS Statistics 26 yazılımı ile gerçekleştirilmiştir. Bu parametreler kullanılarak Regresyon Analizleri RA yapılmış ve eğitim yapılarının maliyetlerini tahmin etmek için denklemler geliştirilmiştir. Geliştirilen modellerle Yaklaşık Maliyetleri ve Sözleşme Bedelleri tahmin edilmeye çalışılmıştır. Oluşturulan denklemlerle tüm parametrelerin kullanıldığı model Yaklaşık Maliyet Bedeli için determinasyon katsayısı R²0.900, Sözleşme Bedeli için ise R²0.927 ile en iyi ilişki düzeyine sahip model olmuştur. Modelin kullanılması ile elde edilen yaklaşık maliyet tahminleri ve gerçek maliyetler arasında 17,5 düzeyinde hata oranı saptanmıştır. Tahmin edilen sözleşme bedelleri ile gerçek sözleşme bedelleri arasında ise 18,2 hata olduğu belirlenmiştir. Tahmin edilen sonuçlar ile gerçek sonuçlar arasındaki tutarlılığı kontrol etmek amacıyla Durbin-Watson kriteri kullanılmıştır. Sonuç olarak, farklı tip ve katsayılarına sahip okul yapılarının yaklaşık maliyetlerini ve sözleşme bedellerini 20den düşük hata oranları ile tahmin edebilen bir yaklaşım oluşturulmuştur. Gerek kamu kuruluşları gerekse taahhütçü yapım firmaları bu modellemelerden istifade ederek zamansal tasarruflar sağlayarak gerçekçi maliyet tahminlerinde bulunabileceklerdir. Benzer çalışmaların veri adetleri arttırılarak yapılması, daha sonraki modellemelerde hata oranı minimizasyonu için bir çözüm olabilir.

Article Details

A Model Proposal for Estimate the Approxımate Costs and Contract Fees of Public Education Buildings (School Buildings)

Authors:

Servet Kesim | Latif Onur Uğur

Publisher:

Duzce University

Main Topics:

Yapı İşletmesi

Journal:

Düzce Üniversitesi Bilim ve Teknoloji Dergisi Vol.13 Issue 1, pp.197-218

Document Type:

Article

Publication Date:

1/2025

Document Language:

English

Document ID (Org No.):

2001339869

pISSN:

2148-2446

Building Cost Model

Multiple Linear Regression Model

School Buildings

Building Cost EstimationYapı Maliyeti Modeli

Çoklu Doğrusal Regresyon Modeli

Okul Binaları

Yapı Maliyeti Tahmini

Issues

Article Details

Authors: Servet Kesim | Latif Onur Uğur

Publisher: Duzce University

Main Topics: Yapı İşletmesi

Journal: Düzce Üniversitesi Bilim ve Teknoloji Dergisi Vol.13 Issue 1, pp.197-218

Document Type: Article

Publication Date: 1/2025

Document Language: English

Document ID (Org No.): 2001339869

pISSN: 2148-2446

Issues

Authors:

Servet Kesim | Latif Onur Uğur

Publisher:

Duzce University

Main Topics:

Yapı İşletmesi

Journal:

Düzce Üniversitesi Bilim ve Teknoloji Dergisi Vol.13 Issue 1, pp.197-218

Document Type:

Article

Publication Date:

1/2025

Document Language:

English

Document ID (Org No.):

2001339869

pISSN:

2148-2446