Documents & records
Redline drawings
Also called: markup drawings, red-lines
Redline drawings are the working set the field marks up in real time — literally in red — to capture what actually got built where the plans said something else: a rerouted line, a relocated cleanout, a dimension that shifted, a change from an RFI answer. They're the primary record kept as the work goes in, and they're what a clean as-built drawing set is later drafted from. If a change isn't red-lined when it happens, it's usually lost.
Why it matters
Field conditions never match the plans perfectly, and the moment to record a deviation is when it's made and still visible — not months later from memory. Redlines are the difference between an as-built the owner's facilities team can trust and a set that quietly disagrees with what's behind the wall.
What proves it
A redline is stronger when it's backed by a dated pre-cover photo of the condition before it was concealed. The markup says what changed; the photo, tied to the location, proves the real routing that no drawing can show once the assembly is closed up.
Checklists that put redline drawings to work
Free, field-ready checklists, each with the photo every item needs before it can be submitted.
Related terms
- As-built drawingsThe construction drawings marked up to show how the work was actually installed, including every field change from the original design.
- Request for information (RFI)A formal written question from the contractor to the design team when the drawings or specs are unclear, conflicting or incomplete.
- Change orderA signed amendment to the contract that changes the scope, price or schedule, agreed by owner and contractor before the changed work proceeds.
- Photo documentationDated, located photographs of conditions and work — especially before they're concealed — kept as the visual record behind inspections and closeout.
- Punch listThe running list of incomplete or defective work a contractor has to fix before an area is accepted and closed out.
- Nonconformance report (NCR)A formal record raised when installed work does not meet the drawings, specs or an accepted standard, and the plan to resolve it.
Knowing the term is step one. Proving it is the job.
RTI holds the submit button until every mandatory item is answered and the photos are attached, then chains the record so it can be proven untouched later.