For laying gullies, siphons, and intercepting traps in building drainage, the quoted cost generally includes which components of work?

Introduction / Context:
Sanitary drainage items such as gullies, siphons, and intercepting traps are measured and paid as complete units of work. The quoted item typically subsumes associated tasks necessary to make the installation functional and compliant, avoiding separate micro-measurement of trivial sub-operations.

Given Data / Assumptions:

• The scope concerns supply and installation of drainage fittings.
• Standard specifications require bedding, alignment, and leak-tight connections.
• Rates include normal ancillary works unless stated otherwise.

Concept / Approach:
Measurement rules bundle related operations—setting and laying, bed concrete (for support and level), and connections—into the principal item so that the unit rate covers a complete installation. This simplifies billing and ensures accountability for performance rather than piecemeal tasks.

Step-by-Step Solution:
Confirm inclusion of setting/laying in position.Confirm inclusion of bed concreting to drawings/specifications.Confirm inclusion of making tight, aligned connections to drains.Therefore, the comprehensive answer is “All of these.”

Verification / Alternative check:
Typical bills of quantities (BOQ) list such items as supply, lay, bed concrete, connect, and test, supporting the inclusive interpretation.

Why Other Options Are Wrong:

• Partial inclusions omit essential operations that are standard with these fittings.

Common Pitfalls:
Overlooking testing and making-good, which are often stipulated alongside; underestimating bedding requirements in soft ground.

Final Answer:
All of these.