SIA 118/262:2004 – General Conditions for Concrete Construction
The SIA 118/262:2004 is a registered Swiss standard (SN 507 262) issued by the Schweizerischer Ingenieur- und Architektenverein (SIA). It serves as a set of general contractual conditions for concrete construction within the Swiss legal framework for building works. This standard belongs to the Allgemeine Bedingungen Bau (ABB) series and supplements the basic standard SIA 118 by providing specific regulations for the conclusion, content, and processing of contracts in the field of load-bearing structures and concrete construction.
The scope of the document governs activities related to Betonbau (concrete construction) and Stahl-Beton-Verbundbau (steel-concrete composite construction). It defines organizational terminology such as Gesamtleiter (project manager), Kontrollplan (control plan), and Prüfplan (test plan), while establishing the regulatory requirements for quality management levels. The document is structured into a general part covering the Werkvertrag (contract for work) and a special part dedicated to technical execution details including shuttering, reinforcement, and precasting.
This standard replaces several earlier regulations, including the organizational parts of SIA 162 (1993) and SIA 220 (1992). It becomes legally binding when the contracting parties explicitly designate it as a component of their agreement.
Contractual Roles and Responsibilities
Section 1.3 outlines the distribution of tasks between the Bauherr (client) and the Unternehmer (contractor). These tasks must be regulated clearly before the start of design and execution.
- Client Tasks: Coordinating specialists, obtaining necessary permits, and creating the Kontrollplan (control plan) to define quality requirements.
- Contractor Tasks: Designating a Baustellenchef (site manager), creating the Prüfplan (test plan) and construction program, and ensuring occupational safety according to SUVA guidelines.
- Quality Management: The client defines the level of quality management required, ranging from Stufe I (standard professional practice) to Stufe III (certified system according to SN EN ISO 9001).
Technical Provisions for Concrete Works
Section 8 defines the technical requirements for the execution of concrete structures, covering materials, formwork, and reinforcement.
- Schalungen (Formwork): Differentiation between four types of surface quality, from Typ 1 (normal surface) to Typ 4 (fair-faced concrete with panel structure).
- Bewehrungen (Reinforcement): Includes the provision of documentation for manufacturer quality proofs and the correct binding and fixing of bars.
- Spannsysteme (Prestressing): Covers the handling of tendons, duct sealing, and the creation of injection protocols.
- Beton (Concrete): Specifies three standard types—Sorte A, Sorte B, and Sorte C—classified by compressive strength, exposure classes (e.g., XC2, XC3, XF1), and maximum chloride content.
Compensation and Measurement Rules
Sections 8.4 and 8.5 establish how concrete works are measured and compensated to ensure a uniform basis for billing.
- Measurement of Formwork: For wall and slab formwork, openings with an area of ≤ 2.0 m² are measured as if they were solid surfaces.
- Reinforcement Calculation: The weight of reinforcement steel is determined based on the cleaned iron list using a specific weight of 7850 kg/m³.
- Concrete Volume: For shuttered components, the volume is calculated according to the plan; for concrete poured against earth or rock, the actual delivered quantity is measured.
- Precast Elements: Betonfertigteile are generally measured per piece according to the plan.
Compensation for site facilities offered on a monthly or weekly basis is calculated pro rata at 1/30 per calendar day or 1/7 per calendar week for incomplete periods.
Frequently Asked Questions
What happens if SIA 118 and SIA 118/262 contradict each other?
According to section 0.2, in the event of a contradiction, the provisions of the specific standard SIA 118/262 take precedence over the general SIA 118.
Who is responsible for the static calculations of temporary site structures?
Under section 1.2.1, the contractor is responsible for the static calculations of site facilities, scaffolding, and other auxiliary structures.
How many quality management levels are defined in SIA 118/262?
There are three levels: Stufe I (no formal system required), Stufe II (documented system required), and Stufe III (ISO 9001 certified system required).
Are reinforcement spacers included in the standard price?
Yes, the delivery and installation of spacers for reinforcement are listed as included services under section 8.2.3.
At what temperature are special measures for concrete required?
Special measures must be compensated separately when the outside temperature is below +5 °C or above +30 °C, as per section 8.4.6.3.
What is the standard curing period for concrete if not otherwise specified?
If more specific information is missing, concrete must be processed and cured for a period of 5 days according to section 8.2.5.
