Aleksandr Skidan

Aleksandr Skidan, PhD of Economic Sciences and Associate Professor at the Department of Construction Economics and Housing and Utility Infrastructure, proposed a methodology for generating cost estimates based on a digital information model (DIM) as part of a grant for research by SPbGASU faculty in 2025. The study explains why estimates need to be digitized, what problems this solves, and who will benefit most from these solutions.

Traditional estimates rely heavily on two-dimensional drawings and manual calculations, which are a source of errors, wasted time, and controversial comments during expert assessments. The study demonstrates that with proper integration of the DIM, estimate data can be automatically extracted from the model, reducing human error and increasing process transparency. The study establishes a methodology for interaction between designers, estimators, clients, and experts in a unified digital space.

Stage	Designer / TIM specialist	Estimator	Technical customer	General contractor	Expertise
DIM development and attribute filling	Generates a model, introduces attributes	Provides consultation on cost estimates	Approves requirements for the content and quality of data	Gets informed about the structure of the DIM	–
Extraction of the BoQ	Prepares BoQ data in digital form	Checks the correctness of the parameters and forms the structure of the future estimate	Controls data completeness	Receives preliminary quantities	–
Assignment of estimate standards	Provides classified model elements	Compares the elements of the DIM with the standards of the CSD	–	–	–
Cost calculation and estimate generation	Ensures the correctness of the source data, makes changes, records the GUID and parameters	Performs cost calculations and generates estimates	Controls estimate indicators	Getting acquainted with the calculation	–
Preparing data for examination	Exports DIM and related data (IFC, XML)	Generates CBoQ and estimates, checks for completeness (GGE XML)	Monitors compliance with requirements	Receives the final document	Checking volumes and costs by ifcGUID
Expertise and approval	–	Provides advice on expert comments	Chief approver	Gets informed	Conducts an inspection and issues a conclusion

The study describes a set of practical rules and a matrix of responsibilities for each participant in the formation of estimate documentation: unified glossaries of terms and attributes for the model, requirements for the level of detail (LOD) for estimating purposes, data transfer regulations, and automatic estimate downloads in XML format.

Main advantages and practical benefits:

Who needs this right away?

Public and private customers – for more reliable budget control and transparency in the use of funds.

Contractors – to quickly respond to project changes and have an up-to-date estimate when negotiating with subcontractors.

Banks and investors – a more accurate assessment of the cost and risks of a project.

Software and standards developers, the methodology specifies technical integration points (IFC, TIMML, XML), which is important for plugins and converters.

Estimators and DIM specialists – a transition to the role of analyst and coordinator, and not just a table assembler.

The developed methodology recognizes that the transition will require effort: standardizing terminology, setting up parameter templates, training estimators to use the model, and adapting software from different manufacturers. It is useful to rely on existing regulations and orders from the Ministry of Construction / GOST standards, which already provide the regulatory framework for integrating the DIM into estimating practice.