Hiring an MEP Consultant for a Brownfield Factory: Surveys, As-Builts and Compliance Gaps

An MEP consultant for a brownfield factory should do four things before drawing anything new: survey the plant while it runs, rebuild as-built drawings for what is actually installed, compare that installation with current rules to list the compliance gaps, and phase the new work around production. Hire on that scope. A fee for new design alone leaves the existing plant as the unknown.

Why is a brownfield factory harder to design than a new one?

In a new building the drawings are the installation. In a plant that has grown for fifteen years they are a record of intentions. Feeders were added, a transformer was swapped, a compressor house moved, and the single-line diagram stayed in the stores. Three consequences follow for the consultant.

• Capacity is unknown. Nobody can say how loaded the transformer, the main LT panel, the DG set, the chilled-water plant or the fire-water tank really is, so any new load is a guess until it is measured.
• Undocumented changes are a compliance issue. Under regulation 45(6) of the CEA safety regulations 2023, an owner who adds to or alters an installation may not connect the alteration until it is approved in writing by the Electrical Inspector or self-certified, as the case may be. Additions that never reached the inspector's file are a gap by definition.
• Production sets the schedule. The work happens in shutdown windows, with a running plant on the other side of the wall.

What should the survey cover?

The survey is the largest part of a brownfield fee, and the part most often cut. Done properly it produces measured data, not impressions. Our checklist for the site visit is in the brownfield survey note; the table shows what each discipline yields.

How are as-built drawings reconstructed?

By walking the plant with the old drawings and correcting them. The surveyor traces each feeder from the panel to its load, reads cable tags and breaker ratings, measures routes and levels, and records what could not be verified. Good practice is to mark every item on the drawing as measured, traced or assumed, so the design team knows which numbers to trust and which to re-check before ordering equipment.

Where congestion is the risk, such as a new chiller plant threading through existing pipe racks, a laser scan of the area gives a measured model to design against. Whether it pays for itself depends on the clash risk; our note on BIM for a factory sets out the trade-off. Live panels are opened and measured only by designated persons. Regulation 3 of the CEA regulations requires the owner, and any contractor engaged, to designate persons who hold a certificate of competency or work permit, entered in a register.

What does a compliance gap review cover, and what is it not?

It compares what is installed with what is required today and lists the differences, so that the design and the budget carry them. The reference points are:

• Electrical safety duties. Regulation 5(3) requires a factory with more than 250 kW connected load to designate an Electrical Safety Officer, who inspects at intervals not exceeding one year and keeps the records. Regulation 32 sets periodic inspection or self-certification at an interval the state directs, not exceeding five years, and regulation 32(8) makes the owner responsible for keeping the installation free from danger.
• The approvals on file. Does the electrical file match the installation? Is the Fire NOC current and does it cover the present building and stock? Our guides to CEIG approval and Fire NOC for factories show what is checked.
• Fire design for the hazard. The National Building Code 2016, Part 4, notes in its table of fire-fighting requirements that for industries other than small-scale units the requirements are worked out from the relevant Indian Standards with the local fire authority. The consultant's job is to state the hazard class per area and test the installed systems against it.

It is not a statutory certificate. Inspection of an installation above the notified voltage belongs to the Electrical Inspector, and fire clearance to the fire authority. We do not sell audits; the gap review is part of the design work, and its output is a rectification scope and a design, not a pass or fail.

How is the work phased around production?

The usual order is to add capacity in parallel, cut over in a planned shutdown, and decommission the old plant last. In practice that means new transformer or chiller capacity energised alongside the old, new panels built off-line and swung in on a shutdown, and fire and ELV extended zone by zone with temporary cover kept live. Four checks belong in the plan:

1. The shutdown windows the plant can really give, and the work that fits inside each one.
2. Temporary supply for anything that must not stop, such as a cold room or a furnace cooling circuit.
3. Permits for hot work and for working in live panels, owned by a named person on each side.
4. The approvals sequence. A material alteration reopens the inspector's file, and an installation shut down for six months or more must be inspected, tested and certified again before supply resumes (regulation 45), so a long idle section can turn a restart into an approval event.

For a first budget, the MEPF cost calculator gives an order of magnitude. Replace it with a bill of quantities once the survey fixes the scope. Our guides on evaluating an MEP consultant and on how design fees are structured help you compare proposals.

How Secured Engineers helps

We design MEPF in-house, and we file the Fire NOC, CEIG and DISCOM applications ourselves, so the survey findings flow straight into drawings and approvals. MEPF and solar can sit under one contract. We work from Noida (Delhi NCR) and Ludhiana, across 535+ projects in 18+ states, with 89.77% repeat clients. For an existing plant we offer MEP design consultancy and a technical review of drawings, not audits.

If you have the existing drawings, the last year's electricity bills and a list of the new loads, send them for a design review before you tender. We will say what the drawings can and cannot support and what the survey must measure. See our MEP design and approvals service, message us on WhatsApp, call +91 70099 85817 or ask for a free proposal.