IFC drawings

Drawings pass through several statuses as a design develops. A typical sequence is preliminary or for information, then for coordination or review, then for tender, then issued for construction. Each issue gets a revision code and a status so everyone knows what the drawing can be used for.

IFC status means the designer has finished the design for that element, coordinated it with the other disciplines as far as they can, and is happy for it to be built. Builders usually won't let trades start work until the relevant IFC drawings are on site.

In design and construct contracts, the contractor's own design consultants issue the IFC set, often after the principal's team has reviewed it. In a traditional construct-only contract, the principal's consultants issue them.

IFC status doesn't mean the design is frozen. It means it is ready to build from today. Designers still answer RFIs, approve shop drawings and issue later revisions as the job progresses, and each of those revisions carries the same IFC status until it is superseded.

• Tender drawings. Issued so contractors can price the job. They may be incomplete and are not meant to be built from.

• IFC drawings. The approved set for construction. Any change from the tender set may affect price and time.

• Shop drawings. Prepared by subcontractors or fabricators to show how they will make or install their part, based on the IFC set.

• As-built drawings. Prepared at the end of the job to show what was actually built, including changes made on site.

IFC drawings are rarely issued once. Design changes, RFI answers and coordination fixes lead to new revisions throughout the job. The real risk is not the change, it is someone building from the old revision.

Good practice is to issue every new revision with a transmittal, update the drawing register, mark superseded drawings clearly, and remove old prints from site sheds and subcontractor packs. Many builders now use a single digital drawing set so the field team always opens the current revision.

Compare each new IFC revision with the last, and with the tender set, to find changes in scope. A revised IFC drawing that adds work may be a variation, so raise it promptly under the contract.

• Building from tender or superseded drawings. Always check the drawing register before setting out or ordering materials.

• Starting without IFC. Starting work on preliminary drawings to save time often means rework later.

• Missing revision clouds. Not every designer clouds every change. Compare revisions properly rather than relying on clouds.

• Not pricing the difference. Changes between tender and IFC drawings can be claimable. Review the IFC set against what you priced.

• Uncoordinated disciplines. Clashes between structural, architectural and services drawings often only appear on site. Check key interfaces and raise RFIs early.