Preliminary Engineering That Turns the Concept Into a Decision
Basis of Design, Stage B: where the BoD-A concept is pushed further, tested against vendor engagement and procurement reality, and developed to roughly plus or minus 20 percent, so you can commit capital with confidence.
- Develops the concept to a tighter cost accuracy, around plus or minus 20 percent
- Brings supplier reality in: vendor engagement, quotations and tender packages
- Multi-discipline design development with a formal design review and risk register
- Full or Lite: developed only as far as the decision actually needs
- Part of SHV Energy
- ISO 50001
What This Service Is
Preliminary Engineering, or Basis of Design Stage B, is where EM3 takes a concept that has already been established in BoD-A and develops it into a more defined, more testable and more commercially reliable engineering package. It is the concept-development stage that sits between BoD-A and BoD-C, and it is associated with an accuracy band of roughly plus or minus 20 percent.
What changes at this stage is the level of confidence. BoD-A is about defining the concept and proving there is a credible project worth developing. BoD-B is where that concept gets pushed further, so you can understand whether the selected direction still holds up once more engineering detail, procurement input and design discipline are applied. It is the point where EM3 moves on from the estimates and assumptions of BoD-A toward a developed engineering estimate informed by vendor engagement and quotation evaluation, so supplier reality starts entering the picture. It is typically used when the concept could still vary significantly and you do not yet have a clear enough vision to go straight to BoD-C.
Governing standardBasis of Design (BoD-B)
The Challenge It Solves
Right before BoD-B, the client usually has a project concept that looks promising, but it is still not sufficiently defined for a confident capital decision or for a move into full issue-for-tender engineering. The concept may be technically sound in principle, but there is not yet strong enough confidence around the real scope, the design maturity, the procurement implications, the updated cost, or whether the preferred solution will still make sense once suppliers and more detailed engineering inputs are brought in.
This is most relevant where large variations in the concept are still possible and the client does not have a clear enough vision to go straight to BoD-C. They are no longer choosing between broad ideas, but they still need one selected path refined enough to make a stronger decision on cost, direction and the next engineering step.
- A promising concept, but not defined enough to commit capital to
- No firm confidence on scope, procurement implications or updated cost
- Unsure whether the preferred solution survives contact with suppliers
- Not yet clear enough to move straight into tender-ready engineering
How EM3 Delivers It
Start from the concept
We take the output of BoD-A or feasibility and move it into a structured engineering development phase, run under a governed engineering procedure with defined roles, templates and process steps inside our quality system, not as an ad hoc exercise.
Test against vendor reality
We move on from the assumptions and estimates of BoD-A toward a developed engineering estimate informed by vendor engagement and quotation evaluation. This is where supplier reality starts entering the picture and the concept gets tested commercially, not just on paper.
Develop the design across disciplines
We develop the design under the architectural, civil and structural, mechanical, electrical, controls and equipment headings, confirming permitting and EHS impacts and validating energy savings through a heat and mass balance.
Formal design review and risk
We run a formal design review with design risk assessments, a risk-mitigation strategy and tracked actions, so the developed concept is challenged and de-risked before procurement, not after.
Procurement and value engineering
We prepare the procurement inputs: tender packages for the major equipment carrying our design specifications and requirements, budget pricing and any value-engineering opportunities, so the project is ready for the market.
Deliver the developed package
It comes together as a more developed Basis of Design to roughly plus or minus 20 percent, with an updated budget estimate, programme, commissioning protocols and drawings, ready for procurement or the next detailed-engineering stage.
What You Receive
A developed Basis of Design
A fuller BoD-B package to roughly plus or minus 20 percent accuracy, with noticeably stronger technical definition than BoD-A.
Multi-discipline design development
Detailed development across mechanical, electrical, automation and civil, taken to tender stage.
Procurement-ready tender packages
Tender packages for the major equipment carrying our design specifications and requirements, plus tender analysis.
A formal design review and risk register
Design risk assessments and a formal design review with tracked actions and a mitigation strategy.
An updated cost and value view
An updated budget estimate and any value-engineering opportunities, so the commercial picture is current.
A Lite route, where it fits
Where you only want a narrowed commercial view, a BoD-B Lite delivering a cost estimate and a savings-and-feasibility summary.
Proven Outcome
On a heating-decarbonisation project at a manufacturing site, EM3 had already completed an initial feasibility study and presented several options. The BoD-B work took one selected option forward into a Basis of Design B, developing it to roughly plus or minus 20 percent. The client was offered the full package and a lighter route limited to a cost estimate and a savings-and-feasibility summary, a clear illustration of how BoD-B turns an earlier concept into a more mature, costed engineering decision.
And BoD-B is not always needed. Where a BoD-A concept is already mature and big changes are no longer expected, EM3 will recommend skipping straight to BoD-C rather than adding preliminary refinement that would not earn its keep. The point of the stage is confidence, not paperwork.
Why EM3
Part of a staged pathway
We refine the concept into a firm, costed solution with detailed site survey, technical design, an updated business case and technology and vendor selection, with the downstream delivery consequences in mind, not engineering detail for its own sake.
Independent at the procurement gate
We are not tied to hardware vendors or software sales, which matters most at exactly this stage, where procurement, tendering and equipment evaluation start to shape the project. It is a structured decision point before procurement, where an independent technical view has real value.
A governed engineering stage
BoD-B is run under a formal procedure with defined roles, templates and process steps inside our quality system, so it is a rigorous, reviewable engineering stage rather than a proposal dressed up as one.
Right-sized to the decision
Full BoD-B or a lighter route, and an honest recommendation to skip the stage entirely when a BoD-A concept is already mature enough. We develop only as far as the decision needs.
How We Engage
Frequently Asked Questions
How is BoD-B different from BoD-A?
BoD-A defines the concept and proves there is a credible project, to roughly plus or minus 30 percent. BoD-B develops that concept further, to roughly plus or minus 20 percent, testing whether the selected direction still holds up once more engineering detail, procurement input and design discipline are applied.
When do we need BoD-B?
When you have a promising concept that still is not defined enough for a confident capital decision or a move into full tender engineering, especially where large variations are still possible and you do not yet have a clear enough vision to go straight to BoD-C.
Do we always need BoD-B?
No. Where a BoD-A concept is already mature and big changes are not expected, we will recommend skipping straight to BoD-C rather than adding preliminary refinement that would not add value.
What is a Lite option?
Where you only want a narrowed commercial view, we can deliver a BoD-B Lite: a cost estimate and a savings-and-feasibility summary, rather than the full engineering and procurement development.
How accurate is the cost at this stage?
A Basis of Design B is typically developed to around plus or minus 20 percent, tighter than BoD-A, because it is now informed by vendor engagement and quotation evaluation rather than internal assumptions alone.
Do you start engaging suppliers at this stage?
Yes. BoD-B is where supplier reality enters: we move from BoD-A assumptions toward a developed estimate informed by vendor engagement and quotation evaluation, and prepare tender packages for the major equipment.
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