Fit-outs change on site. A partition moves, a door is rehung on the other side, a duct or cable route above the ceiling isn't where the drawing shows it. As-built drawings are the record of those changes, and the client will ask for them at handover.

When I was a senior site manager, producing the red-line drawings was part of my job. This article covers what as-built drawings are, how they differ from record drawings, and how to keep them so they aren't a rush at the end.

What are as-built drawings?

As-built drawings are the construction issue drawings, marked up on site to show what was actually built. The changes are usually drawn in red pen, which is why they're often called red-lines. The marks show where the finished work differs from the design: changes, additions and anything moved.

The contractor marks them up as the work goes. Trade contractors record what they installed and where.

As-built drawings or record drawings?

People use the two terms for the same thing, but they aren't quite the same.

As-built drawings are the marked-up site set. Record drawings are the clean, redrawn version that includes all the as-built information, normally produced by the design team from your mark-ups. The record drawings become the definitive reference for the finished project.

Check which one your contract asks for, and who is doing the redraw. If nobody has been asked, it tends to land on you at the end of the job, when there's least time for it.

On projects that use BIM, the model should be updated with the construction changes and handed over as the asset information model. The principle is the same: what's handed over should show what was built, not what was designed.

Where they end up

As-built or record drawings are normally part of both the O&M manual and the health and safety file. The RIBA Plan of Work puts the building manual, the health and safety file and the fire safety information together at the handover stage, and drawings feed into all three.

One set of drawings, kept properly, can serve every document that needs it. O&M manual or health and safety file? explains how the two documents should refer to each other rather than repeat each other.

How to keep them

What works is simple, and most of it is habit:

  • Keep one master set of the construction issue drawings on site, and mark up only that set.
  • Mark each change on the day it happens.
  • Date and initial every mark.
  • Hand the marked-up set to whoever is redrawing it well before practical completion.

The biggest risk is having more than one set. When changes are marked on whichever copy is nearest, nobody has the full picture at the end, and someone has to piece it together from memory.

Red pen has its limits too. On drawings that already use several colours, red marks can be hard to pick out. Agree at the start how changes will be shown, so the person redrawing them can read every mark.

What to mark on a fit-out

On a typical commercial fit-out, these are the changes that matter most to whoever looks after the space afterwards:

  • partitions and doors that moved from the drawing
  • service routes above ceilings and inside walls
  • isolation points and access panels
  • anything a maintenance engineer would need to find later and can't see

The last one is the test I'd use for everything else. If someone opening up the ceiling in five years' time would want to know about it, it should be on the drawing.

Frequently asked questions

What are as-built drawings?

They're the construction issue drawings marked up on site to show what was actually built, including any changes from the design.

What's the difference between as-built drawings and record drawings?

As-built drawings are the marked-up site set. Record drawings are the clean, redrawn version produced from them, usually by the design team.

Who is responsible for as-built drawings?

The contractor normally marks up the changes on site, and trade contractors record what they installed. Who produces the final record drawings depends on your contract, so check it at the start of the job.

What you get if you hand it over

We compile a Digital O&M & H&S File, from information you supply us, with your Company branding. You will receive a complete Digital O&M Package that complies with the BSA Golden Thread, in accordance with ISO9001, Section 7.5.2.

Request a call or email david@habgoodmanualsolutions.co.uk.

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