Construction can start on a partial set of drawings. It cannot start well on an unready one. Before a contractor mobilizes to an industrial site, a specific set of engineering deliverables needs to exist at “issued for construction” status for the areas being worked. Below are those deliverables, what each is used for on site, and the signs that a package is not ready.
What are engineering deliverables?
Engineering deliverables are the drawings, lists, datasheets, specifications and calculations produced by the design team. Before construction, the ones that matter most are those a contractor uses to plan, procure, fabricate, install and inspect.
Key deliverables and how the site uses them
| Deliverable | Used on site for |
|---|---|
| Plot plan and general arrangement drawings | Setting out, area planning, crane and laydown locations |
| P&IDs | Understanding systems, defining test packages, identifying tie-ins |
| Civil and foundation drawings | Excavation, reinforcement, anchor bolts and embedded items |
| Structural steel drawings | Fabrication and erection sequence |
| Piping GAs and isometrics | Spool fabrication, erection and weld mapping |
| Line list and piping specifications | Materials, test pressures, insulation and painting |
| Equipment datasheets and vendor drawings | Foundation checks, setting and nozzle orientation |
| Single line diagrams | Power distribution and panel installation |
| Cable schedules and routing drawings | Tray installation, cable pulling and termination |
| Instrument index, hook-ups and loop diagrams | Instrument installation and loop checks |
| Material take-offs | Procurement and material control |
What “issued for construction” should mean
An IFC drawing has been checked, approved and released, with its holds cleared or clearly marked. A drawing carrying a clouded note such as “hold, awaiting vendor data” is not construction-ready for that area. Holds should be logged and tracked, and the site should know which work fronts they affect.
Signs a package is not ready
- Vendor data for major equipment is still preliminary
- Piping isometrics were issued before stress analysis was final
- Cable schedules exist without confirmed equipment loads
- Tie-in points on a brownfield site have not been field verified
- More than one revision of the same drawing is in circulation
Any one of these can stall a work front. Several together usually mean the design schedule was squeezed to protect a construction start date, which tends to cost more time than it saves. The coordination practices that prevent these gaps are covered in mechanical, electrical and instrumentation design coordination.
Release deliverables in construction order
Not every drawing is needed on day one. Civil and foundation drawings come first, then structural steel, then equipment and piping, then E&I. A good design schedule releases deliverables by construction area in that order. It is the same logic used in planning structural fabrication: issue what the site needs next.
Engineering status should also be one of the items confirmed in an industrial site readiness checklist before mobilization.
Deliverables become the handover record
Most construction drawings are revised to as-built status at the end of the project. Tracking them properly from the start makes managing handover documentation much easier.
Apex Core Engineering prepares and reviews engineering packages through its design services. Deciding which deliverables a project actually needs is covered in how to scope engineering design.
Frequently asked questions
What does IFC mean?
Issued for construction. It is the revision status showing a document is approved for building.
Can construction start before every drawing is IFC?
Yes, in areas whose drawings are IFC. Work in areas with open holds should wait until those holds are cleared.
What is a hold on a drawing?
A marked part of a drawing where the design is incomplete, usually pending vendor or interface data.
Ask Apex Core Engineering to review your engineering package before construction starts.