Project Detailed Design in Construction: Documents, Budgets & Safety

UNIT 5: THE PROJECT OR DETAILED DESIGN

Role of the Project

A project consists of a series of documents that define the construction work, allowing any professional to manage the project based on these documents. The functions of the project are:

• To verify and confirm the assumptions and solutions from previous stages.
• To provide all the technical, economic, and administrative information to the sponsor.
• To provide technical data, construction details, and conditions under which the project must be executed.
• To serve as a management document in cases where the initial draft is insufficient or nonexistent.

Types of Projects

• Utility/Public Administration Projects:

  These projects are promoted by the Administration and have a rigid structure defined by specifications stipulated in the initial competition. They have predefined documents that must be included.

• Private Sector Projects:

  These projects tend to prioritize functionality and give greater freedom to the designer, who seeks to synthesize the content of all documents. The documentation submitted is the minimum necessary to carry out its implementation.

• Thesis Project:

  This is an academic exercise to confirm that the author has acquired and knows how to apply the expertise of their field of study.

Project Documents

• Report: A document that describes the project.
• Maps: Graphical representation of the project.
• Technical Specifications (Optional): Describes the mathematical elements that make up the work and regulate its implementation.
• Budget: States the cost of the work, with unit prices expressed and decomposed.
• Health and Safety Study.

Memory Contents

The memory is a detailed statement of the project, a comprehensive collection of data, studies, and calculations made during the project's design. Its contents are:

• Specification: A detailed record of the project.
• Justification Report/Calculations: A collection of all design calculations that justify the decisions made.
• Planning: Required if the project budget exceeds €60,000 and for government projects.
• Annexes: Special studies on specific aspects.

Types of Plans and Features

Plans are comprehensive graphical representations of all the items defined by the project. They are flat geometric projections of the work that define its 3D form. They show dimensions, linear dimensions, area, and volume of all buildings and construction works.

The number of plans required will vary depending on the project. They must be standardized according to UNE, avoiding large and unwieldy formats.

- Location Maps:

- Show the location of the project in relation to its environment, at a greatly reduced scale.

- Clearly show the progress of work within a municipality, county, etc.

- Plans of Space or Mass: Outline the boundaries of the project area.

- Flat Topography and Layout:

- Topographical: Required if the original site necessitates earthworks in large volumes. Must set out the contours and transverse and longitudinal sections to determine the volume of excavation and fill.

- Layout: Define the main axes of the works against the edge of the field.

- Plans for General Distribution and Construction Plans:

- Should be sufficient to define the work in its constructive aspects.

Scales and Formats

A4: 210x297mm

A3: 297x420mm

A2: 420x594mm

A1: 594x841mm

A0: 841x1189mm

2A0: 1189x1682mm

4A0: 1682x2378mm

Scale: Drawing / Reality

Reductions: 1:1 / 1:2 / 1:2.5 / 1:5

Extensions: 2:1 / 5:1 / 10:1

Document "Statement of Conditions"

This is the most important document during the project's execution phase. It regulates the relationships between the owners, the project developer, and the contractors who will carry out the work. It consists of three parts:

• General Conditions: Legal and administrative aspects.
• Technical and Individual Specifications: Specifications for materials, equipment, and implementation.
• Particular Administrative Clauses: Economic conditions, including how to measure the work carried out, the rates, and payment terms.

Development and Submission of Tender Documents

The bid must define the works to be executed, the conditions of the materials used, the characteristics of the facilities available, the quality controls to be set, the checks and tests to be performed, the requirements of the construction methods to be employed, and the way to measure, assess, and pay for all the construction units that comprise the project.

Order Book

The order book is mandatory in all building work. Senior and technical staff should review the findings, orders (from the builder), and any assistance required during the development of the work. It must be present on the site at all times.

Budget

The budget should contain measurements, a unit price table, decomposed prices, and the overall budget. It is the document that reflects the cost of the project, i.e., the investment needed to carry it out. It does not cover the operating costs that the project will generate once built. To create the budget for a project, it is necessary to determine the work units and their unit prices.

Typical failures in budget calculations include shortcomings in measurements and faulty unit pricing.

Outline of Budget Making

Units of Work

Each of the parts into which a project can be divided and measured. It will consist of various materials to be specified, a contribution of labor, and the use of tools and machinery for processing.

State Measurements

A set of operations performed on each unit of work to obtain its quantities. The measurement is the size of each unit of work.

Cubing: Determining the volume of work units.

Prices: Indirect Costs and Direct Costs

- Direct Costs of the Work:

- Labor: bonuses, charges, social insurance, etc.

- Materials

- Personnel costs, fuel, energy, etc.

- Depreciation and maintenance costs.

- Indirect Costs of the Work: Setting up offices on site, communications, storage, etc.

Overhead Work

• Costs of ancillary facilities.
• Costs of electricity and water.
• Own staff costs of work.
• Labor costs of auxiliary units.

Business Overheads

• Cost of the facilities of the registered office of the company
• Cost of staff on site
• Cost of funding the work
• Costs incurred by the Treasury to pay taxes

Industrial Benefit

This is the profit that the company tries to obtain from the work to be executed by applying a percentage to the cost deducted from the above concepts.

Constraints:

• Law of supply and demand
• Economic and commercial policy of the company
• Economic and financial situation of the company

Budget Bid

Defined as the amount for which the company agrees to do the work.

Price Revision

An act by which the state recognizes that a construction company has increased the price of a work contract from a certain date due to rising prices.

Methodology for the Implementation of Budgets

- The Material Execution Budget (PEM) and the Contractual Performance Budget (CEP) are the sum of the different budget items. The budget for the execution of works contracted by the State and its autonomous bodies will increase the encoded overhead structure by a percentage:

- 16-20% set by the Ministerial Department in respect of general business expenses (expenses, tax, etc.).

- 6% for Industrial Benefit.

- The General Budget for the information of the Administration (PCA) consists of the sum of all PEC budgets to be paid by the Administration to entities other than the contractor that do not perform actions.

Study of Safety and Health in Construction

The promoter must include a safety study during the drafting stage when:

• The contractual operating budget is less than €450,000.
• The project will last longer than 30 days, using more than 20 workers simultaneously at any one time.
• The volume of estimated labor exceeds 200.
• The project involves the construction of tunnels, galleries, underground pipelines, and dams.

This study shall include: specifications, special conditions, drawings, measurements, and a budget.

In projects that do not require this study, the developer will be required to conduct a baseline survey of health and safety.

Basic Study of Safety and Health

This study will be prepared by a qualified technician appointed by the developer or a safety coordinator.

It shall specify the health and safety standards applicable to the work and identify preventable and non-preventable risks.

It shall refer to forecasts and information to be used in the daily management of safety and health in subsequent works.