Start with the scope, not the price
Comparing totals before scope is the most common tender review mistake. Two MEP bids can differ by a large margin simply because one includes the district cooling energy transfer station, the substation civil works interface or kitchen extract and the other does not. Build a scope matrix first: one row per system (HVAC, chilled water, ventilation and smoke control, plumbing, drainage, firefighting, fire alarm, electrical LV, ELV, BMS, lightning protection, external services) and one column per bidder, marking included, excluded, qualified or silent.
Pay attention to boundaries between packages: who supplies and who installs the generator, lifts power and interfaces, pool and fountain MEP, kitchen equipment connections, landscape irrigation, façade lighting, car park ventilation and CO detection, and the building's connection to the utility network up to the plot limit.
- Interfaces with lifts, façade, kitchen equipment and pool contractors
- Utility connections from plot boundary to building (water, power, drainage, district cooling)
- ELV systems: CCTV, access control, data, MATV, intercom: in or out?
- Builder's work: openings, sleeves, plinths, plant room civil works
- Temporary power, water and site lighting for construction
BOQ versus drawings
In re-measurable contracts the BOQ quantity is corrected later; in lump-sum contracts the bidder carries the risk of quantity errors, so a low lump sum based on the client's under-measured BOQ will reappear as a claim or a dispute. Spot-check the largest cost items against the drawings: chiller and AHU capacities and numbers, main chilled-water pipe sizes and lengths, cable sizes for main feeders, busbar runs, duct sheet metal, sprinkler pipe and heads, fire alarm devices and pumps.
Check that units and descriptions match the specification: insulation thickness and type for chilled-water pipes, duct gauge and class, pipe material for drainage and water supply, fire-rated cables where the specification requires them. Items marked "rate only" or with nil quantities need attention because they often carry unbalanced rates.
Exclusions and qualifications
Every bidder's letter carries a list of exclusions, assumptions and deviations. Read them line by line and price them back into the comparison. Typical exclusions that change the picture are authority fees and deposits, builder's work, scaffolding above a certain height, cranage for plant lifting, third-party testing, attic stock and spare parts, BMS integration with third-party systems, and design responsibility for parts of the system.
Qualifications such as "subject to site survey", "as per our standard terms" or "price valid for a limited period" also carry risk. Ask each bidder to withdraw or price each qualification in a clarification round, and record answers in writing as part of the contract documents.
Approved makes and technical compliance
Check every major item against the approved-makes list and specification. A bidder offering an equivalent that is not on the list should provide a compliance statement with data sheets, and the consultant must accept it before award, not after. For chillers, confirm that capacity is stated at the project's design ambient condition and not at a standard rating condition, and that efficiency figures match what the specification and green building requirements demand.
Fire alarm, firefighting equipment and many life-safety products must be Civil Defence approved. Electrical switchgear, meters and connection equipment must meet the utility's requirements. A cheaper non-listed product can trigger rejection at submittal stage and a forced change later.
- Chillers and AHUs: capacity at design ambient, efficiency, refrigerant, coil coating
- Pumps: duty point, motor efficiency, standby arrangement
- LV switchgear: type-tested assemblies, short-circuit rating, utility acceptance
- Fire alarm and sprinkler products: Civil Defence approved listing
- BMS: open protocol, integration points, graphics scope
Contract terms and commercial conditions
MEP subcontracts often fail on terms rather than price. Check payment terms and whether they are back-to-back with the main contract, retention and its release, advance payment and bond requirements, liquidated damages and caps, defects liability period, warranties for major equipment (whether manufacturer warranties start at delivery or at handover), and price escalation clauses for copper, steel and imported equipment.
Confirm design responsibility: in a traditional contract the consultant designs and the MEP subcontractor produces shop drawings, but some tenders quietly transfer design responsibility for parts such as smoke control, pump selection or cable sizing. That changes risk and should be priced and acknowledged explicitly.
Testing, commissioning and handover
Testing and commissioning is frequently underpriced. The tender should state who does pre-commissioning, water and air balancing, BMS point-to-point checks, integrated fire and life safety testing (cause-and-effect with HVAC, lifts, doors and smoke control), third-party witnessed tests where required, and the provision of commissioning engineers from equipment manufacturers.
Handover deliverables also cost money: as-built drawings, O&M manuals, training of the operator's staff, spare parts and attic stock, and support during the authority inspections for the completion certificate. If these are vague, the last months of the project become a negotiation.
Provisional sums and prime cost items
Provisional sums are used for scope that is not defined at tender, such as authority charges, specialist ELV systems, kitchen equipment connections or tenant fit-out. They are legitimate but easy to abuse. Check that each provisional sum has a clear description, that the bidder's profit and attendance percentage on it is stated, and that the total of provisional sums is reasonable compared with measured work.
Too many provisional sums mean the design is not ready for tender. In that case a short period of further design is usually cheaper than awarding an MEP package whose real cost will only be known after award.
How Manolia supports tender review
Tender review sits at the first stage of Manolia's 8-stage delivery process, and our engineering team prepares scope matrices, clarification lists and value-engineering proposals for developers and main contractors. With more than 100 projects delivered since 2001, including towers, hotels and industrial complexes, we know where MEP tenders typically miss scope. Contact +971 54 569 3856 or info@manolia.co.
Frequently asked questions
What is the biggest risk in accepting the lowest MEP bid?
Hidden scope gaps. The lowest bid often excludes items others include, such as authority fees, T&C support, builder's work or cranage, or it offers equipment not on the approved-makes list. Once these are normalised the ranking frequently changes, and unresolved gaps return as variations during construction.
Should the main contractor or the consultant review MEP tenders?
Both, with different focus. The consultant checks technical compliance with the design and specification, and the main contractor checks programme, interfaces with other trades, commercial terms and back-to-back conditions. Where the developer tenders MEP directly as a nominated package, they need the same two lenses.
How do I compare bids with different exclusions?
Use a scope matrix and price each exclusion with an estimate or by asking bidders to price it in clarifications. Add those amounts to each bid to get a normalised total. Record the final clarifications in writing and attach them to the subcontract so the agreed scope is enforceable.
Are provisional sums a sign of a bad tender?
Not necessarily. Some scope cannot be fully defined at tender, such as authority charges or tenant fit-out. But if many core systems are covered by provisional sums, the design is not mature enough, and the final MEP cost will not be known until well after award.
What should I check in the T&C scope?
Who carries out pre-commissioning, air and water balancing, BMS point checks and integrated fire and life safety tests, whether manufacturer commissioning engineers are included, who supports Civil Defence and utility inspections, and what handover deliverables are included: as-builts, O&M manuals, training and spare parts.