MEP Fix Classification

First fix comprises all the work needed to take a building from foundation to putting plaster on the internal walls. This includes constructing walls, floors and ceilings, and inserting cables for electrical supply and pipes for water supply.

Second fix comprises all the work after the plastering to a finished house. Electrical fixtures are connected to the cables, sinks and baths connected to the pipes, and doors fitted into doorframes. Second fix work requires a neater finish than first fix.

The division of work is a convenient description because electricians, plumbers and carpenters will probably have to make two separate visits to one property under construction, at separate times. Project managers can report "first fix complete" or "second fix 50% done" and others can understand.

The installation of this equipment takes place in the "third fix" segment of a construction project. It is especially important that installation of sensitive electronic equipment be installed only when a construction site is dust-controlled and prepared for what would be considered "dust free" conditions

Mechanical:

Plumbing (Drainage/Water Supply & Fire Fighting)

1. First Fix: Surveying, Marking, Supports and Brackets Installation    
2. Second Fix:

• Stage 1: Installation of Main Plumbing Header & Branch pipe
• Stage 2: Insulation of Branch pipe & Installation of droppers with Valve accessories
• Stage 3: Testing of Main & Branch Pipe lines

1. Final Fix: Installation of Hose Bib & Sanitary fixtures (All Exposed Plumbing Items)
2. Equipment Installations: Sump Pump & Water Heater (All Plumbing Long Lead Items)

 

HVAC

1. First Fix: Surveying, Marking, Supports and Brackets Installation
2. Second Fix:

• Stage 1: Installation of Ducts/CHW/Refrigerant Pipe
• Stage 2: Insulation of Branch Ducts/CHW/Refrigerant Pipe & Installation of droppers with Valve Accessories
• Stage 3: Testing of Main & Branch Ducts/CHW/Refrigerant Pipe

1. Final Fix: Installation of Grilles & Diffusers (All Exposed HVAC Items)
2. Equipment Installations: Chillers & AHU's (All HVAC Long Lead Items)

Electrical

1. First Fix: Surveying, Marking, Supports and Brackets , install conduits & back boxes in wall
2. Second Fix:

• Stage 1: Pulling of Cables/Wires & Continuity test i.e. Wiring for internal lights, small power, sockets, Wire pulling to junction boxes & electrical Distribution Boards, DB dressing, Cable tray & trunking
• Stage 2: Termination and Glanding of Cables/Wires

1. Final Fix: Installation of Light Fixtures (All Exposed Electrical Items)
2. Equipment Installations: HV Switch gear & DB's/SMDB's/LCP's (All Electrical Long Lead Items)

Note:
High Level Installations refers MEP Works in Ceiling Void Space
Low Level Installation refers MEP works below the false ceiling board enclosure
Generally MEP Risers are given more importance .It has separate WBS named Risers in which respective risers are mentioned it is not classified in to fixes

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• MEP Fix Classification