Construction Processes: Stages, Technology, and Time Management

Posted on Mar 15, 2025 in Business Administration and Management (BAM)

1. Stage Process Explained

A stage process comprises several building subprocesses that are related in space and technology. These subprocesses follow each other sequentially, typically in one direction, resulting in a technology stage.

Main features of stage processes for analyses:

  • Work items (waterproofing material, scrapers, bolts)
  • Work tools (welding equipment)
  • Labor force (insulation workers, ditch diggers)
  • Working (production) area (min. 600 mm)
  • Intermediate products (fillings, ducts)
  • External influence (ambient temperature, rain, snow)
  • Other important circumstances

2. Technology Stage Defined

A technology stage is a structurally integrated part of a construction property that needs, or is desirable, to be produced jointly (such as foundations, lower structure, or upper structure).

3. Volume of Building Under Construction

The process of volume of buildings under construction comprises inter-related stage processes. The outcome is the volume of buildings under construction. This volume is an integrated part, in terms of production, of a construction property that consists of several technology stages with inter-related purposes (such as a lower structure including earthmoving works and foundations).

4. Homogeneous vs. Heterogeneous Structures

From a technology perspective, structures are classified as either heterogeneous or homogeneous:

  • Homogeneous structures: Individual parts of decisive structures are evenly distributed, meaning labor consumption is also evenly distributed (for instance, apartment buildings where floors are the same).
  • Heterogeneous structures: Individual parts of decisive components are distributed unevenly, and labor consumption varies (for instance, a structure with a more complex solution, e.g., a generation block in a power plant).

5. Understanding Technology in Construction

Technology, as a branch of science, deals generally with production processes. From the point of view of technology, there are:

  • Heterogeneous structures
  • Homogeneous structures

6. Three Phases of Construction Preparations

  1. Pre-building preparations: Feasibility study, business intention, action area planning, building procedure/building permit (Basic Design), and an offer are drafted.
  2. Building preparations: Detail Design, rules for the Detail Design, and production costing are prepared.
  3. Operation preparations: Subjects and times are updated for the production preparation, and activities needed directly for the performance and construction are carried out (including operative plans, orders, invoices – all documents are updated depending on the progress of works on site).

7. Pre-Building Preparations Explained

Pre-building preparations include a feasibility study, business intention, action area planning, building procedure/building permit (Basic Design), and an offer. This phase is carried out by the investor and comprises:

  • Business intention / feasibility study
  • Preparation of zoning management documentation
  • Preparation of building permit documentation
  • All negotiations with competent organizations, authorities, and state bodies

The supplier of building works prepares:

  • Offer
  • Fixed job contract within the pre-building preparation

8. Division of Space in Construction Property

  • Performance Part: The space defined for a specific construction of a construction property, for instance, a compensation section of the property where all volumes of works under construction are carried out.
  • Section: The space where a respective technology stage is carried out. Each section has common borders for workplaces within the associated building sub-processes.
  • Workplace: A part of a section in the technology stage that is defined separately for each building process. The border is defined by joints (both structural and working joints) and connections of structures or by the completed structure. The workplace is a basis for the minimum working queue (the working space) because one group of workers can typically work in one workplace.

10. Determining Duration of a Building Sub-Process

The duration of a building sub-process can be calculated by one of two available methods (depending on input data):

  • Natural method: Based on the real labor consumption calculated from a physical volume of production of a certain building sub-process. Physical units are used. It is also possible to use the real labor consumption specified in the operation costing t=z/Pr.d.h.s(days)
  • Financial method: Based on the real labor consumption calculated from the price of the production that is the outcome of a specific building process. It is expressed in financial units.

The financial method is used for PSV processes. The price of production is determined from the building operation budget. Durations of the building sub-processes are typically calculated in the technology analysis – this is the basic document for preparation of the construction. The technology analysis describes the technology structure of the building process.

Minimum number of workers, dmin, is given by the technology of the building process. Maximum number of workers, dmax, is given by the size of the working queue or by supplier’s capacity.

Different numbers of workers or machines in the range from dmax to dmin result in different durations of the building sub-processes: from tmin to tmax

Time of the i th stage process, this means ti , in time units can be calculated as a time of deployment of the i th stage process, T´i , and the time of the last building sub-process, tposl, that takes place in the stage process (in time units).

ti = T´ i + t posl

12. Basic Parts of Site Facility

Basic terms:

  • Construction property
  • Construction
  • Building land
  • Site facilities

Requirements:

  • Security of site facilities, fences, entrance, gates
  • Protection and safety
  • Safe buildings within site facilities
  • Due storage of materials and products
  • Underground, energy, telecommunication, water and sewage networks for site facilities must be identified, in terms of positions and levels, before the handover of site facilities at the latest.
  • It must be possible to lock all entrances to the site facilities.
  • Sidewalks: min. 0.75 m. Two-direction sidewalks: 1.5 m.
  • If inclination is greater than 1:3, there must be a one-side handrail up to 1.1 m. Clearance: 2.1 m (in exceptional cases: 1.8 m + lighting and marking)
  • Built-up area: fencing up to 1.8 m

Types of Site Facilities:

Division by the purpose:

  • Operation site facilities
  • Production site facilities
  • Site facilities for employees

Division by the location and main function:

  • Property-related SF – for a specific property
  • Section-related SF – for a specific section of the site
  • Central SF – for the entire site with several properties

Approximate size of the area for SF is: Pc = Pi + Ps + Pt + Pmd + Po (m2 )

This comprises areas needed for:

  • Pi investment properties
  • Ps SF for the supplier of construction works
  • Pt SF for the supplier of technology
  • Pmd temporary heaps (top soil and excavated materials)
  • Po other parts of SF

13. Stage Processes Influenced by External Conditions

  • Stage process 0 – Earth moving works and demolitions → winter, weather
  • Stage process 1 – Foundations → winter, weather
  • Stage process 2 – Lower shell structure → winter, weather
  • Stage process 3 – Upper shell structure → winter, weather
  • Stage process 4 – Roofing → winter, weather
  • Stage process 9 – Outdoor works → weather

14. Basic Documents of Construction and Technology Project

This is the outcome of construction preparations. A model of the construction process is prepared on the basis of:

  • A space analysis
  • Technology and time aspects of the building process

Basic documents in CTP (STP):

  • Technology chart that analyses the spatial structure of the building process
  • Technology analysis (normal) that analyses the technology structure of the building process
  • Time chart that analyses the time structure of the building process
  • Flow chart that models the technology, time and spatial structures of the construction process or facility
  • Time-and-space chart that analyses the time and space structures of the building process
  • Charts of resources needed in time (finances, labor force, materials)
  • Operative and financial plan
  • Inspection and testing plan
  • Description of site facilities

17. Time Planning in Construction

A proposal of a reasonable time structure of the process is among key tasks of the construction and technology design. Individual components of the time structure need to be addressed: time behavior (duration and times) of lower-level components of the operation process as well as the total duration.

Considering the relations between the technical equipment, technology and organization, the processes can:

  • Follow each other directly or with interruptions
  • Overlap
  • Take place at the same time

TIME SCHEDULE – CYCLOGRAM – NETWORK CHART (each model consists of identification, calculation, graphic and evaluation part)

18. Types of Network Charts

  • Stochastic charts: Use probability to determine a duration of activities
  • Deterministic charts:
    • With defined edges
    • With defined nodes
    Duration of activities is determined by mathematic methods

19. Space Structure in Construction

The space structure consists of locations of production/working areas for a certain production process. The space structure comprises storage areas, transport routes, locations of machines, equipment and distribution lines, and locations of employees in the space as well as spatial relations between all those components.

The space structure changes in the progress of production for different products. The space structure is in accordance with the technology and time structures.

20. Activities in Network Chart with Defined Edges

Network chart with defined edges: activities are identified with the edges.

A network chart with defined edges is a definite directed chart that shows a model of a specific project. The edges represent project activities, while the nodes represent the time. This means, the duration of each activity is given by the value of the network chart edge. For activities in one path: once one activity ends, another activity can start.

Following types of activities exist:

  • Real activity: It is performed and has a specific scope (for instance: placing of concrete for shallow foundations/footings or erection of a steel structure…). It can be valued by means of resources and time. A solid line in the chart describes the real activities.
  • Dummy activity: It represents the relation between the activities. Duration is zero. No resources are needed. A dash line describes the fictive activities.
  • Distance activity: It represents the relation between the nodes and activities (leading times and delays). It poses requirements in terms of the time. Resources are not considered. A dot-and-dash line describes the distance activities.

Real activity i_tij_>j Dummy: i–tij=0–>j Dist i-.-.->j.

If several activities are in the node input and/or node output:

  • Each node (except for the start of the chart) is performed after all activities that end in the node have been completed. This is the conjunctivity of the node input.
  • Performance of any node (except for the end of the chart) means that all activities that start in the node are started. This is the determination of the node output.

21. Creating a Network Chart

  1. Determination of the breakdown of the project into specific activities (the progress of works and technology need to be considered)
  2. Creation of the primary network chart
  3. Gradual changes in the network chart

Relations and links of the activities can be logically derived:

  • By forward operations
  • By backward operations
  • By combined operations

Each network chart must fulfill 3 basic conditions:

  1. It must have one start and one end.
  2. It must be free of cycles.
  3. It must be free of multi-graphs.

22. The Critical Path Explained

In the network chart there is at least one path when the soonest possible start and the latest acceptable end merge. This path represents the total duration of the project – this is a critical (decisive) path.

All other paths are shorter with certain reserves.

23. Building Preparation Defined

Building preparations: Detail Design, rules for the Detail Design and production costing are prepared.

Building preparations:

  1. Production calculation
  2. Detailed time schedule for construction and facilities
  3. Balance of resources: Labour force, Wages, Material, Construction equipment
  4. Third party deliveries
  5. Drawings – site facilities, constructions and facilities
  6. Technology rules (for some processes)

Building preparation is carried out by the supplier. Key outcomes of supplier’s building preparation are:

  • Costing
  • Detailed long-termed plan of the construction for the investment/property
  • Control plan
  • Testing plan

24. Operation Preparation Defined

Operation preparations: subjects and times are updated for the production preparation and activities needed directly for the performance and construction are carried out (incl. operative plans, orders, invoices – all documents are updated depending on the progress of works on site)

Operation preparation is carried out by the site manager on the site. Key outcomes include:

  • Operative plans (week, month, three-month)
  • Test protocols
  • Quality records
  • Invoices for works done (typically for one month)
  • Updated time schedules
  • Information about compliance with construction deadlines
  • Operative records for work done

27. Technology Structure and Time Structure

The technology structure of a building process exists in time and in space. Therefore, it must be described in accordance with the time and space structures of the building process.

The technology structure of the building process comprises:

  • Division of a general process into property-related processes, division of a property process into processes relating to the volume of building under construction, stage processes, and building sub-processes
  • Sequence of property processes, processes relating to the volume of building under construction, stage processes and building sub-processes
  • Technology links between processes.
  • Labour force and structure of the labour force.
  • Work tools and structure of the work tools.
  • Work items and structure of the work items.

Most important parameters in the technology structure:

  • Number of properties, volumes of buildings under reconstruction and technology stages
  • Number of building sub-processes
  • Scope of production
  • Labour consumption
  • Labour productivity
  • Number and composition of labour force
  • Number of machines and equipment

Number of properties is determined on the basis of a layout drawing, technology report of project documentation.

The volumes of buildings under construction and technology stages is generally determined in technology analyses of the property process depending on the space structure of the building process.

The number of building sub-processes is determined using a technology aggregation standard for all procedures that are listed in the analysis sheet for the property or production calculation.

Time structure – parameters and description

The time structure of a building process results from time links with the space and technology analysis of the building process. The time structure cannot be analysed apart from the space and technology structures.

The time structure of a building process comprises:

  1. Time sequence and time schedule of all property processes, stage processes and building sub-processes
  2. Time evaluation of links between the processes (determination of time values for respective links)
  3. Sources needed in time (finances, labour force, materials, machines)

Most important parameters in the time structure:

  1. Duration of a building sub-process
  2. Time and duration of deployment of the stage processes
  3. Time and duration of deployment of the property processes and processes relating to the volume of buildings under construction
  4. Time values of relations between the processes
  5. Starting and ending dates for the building processes.

The time structure parameters are expressed in units of time (days, weeks and months). The starting and ending dates of the building processes can be expressed relatively, this means as a number of time units from the start of construction, or absolutely as a calendar day