D & C versus Full Design

Full Design or D&C?

This post discusses D&C vs Full documentation.

Should I fully document a project or go D&C?  

This question is normally answered by the Architect or the Project Manager at the very outset of a project. This is a fundamental decision point. The rest of the team have no input, indeed the project, or potential project is very often still under wraps.

If you’re going D&C, then the team should be involving D&C (design and construct) contractors (Builder, HVAC, Elec, Hydraulic and so on contractors) from the start.

If this is too hard (D&C contractors involved early), then your heading for the Full Design approach with usual consultant input or the half-way house, where the team (including Architect and Consultants), get the project to say 30% and then start the D&C process (The hope is that the 30% work is not abortive).

Basically it comes down to hard dollars (again) and trust. The hard dollars (will I get a cheaper price if I fully document and go to competitive tender) and the trust (can I trust a D&C contractor not to rip me off).

My Views

I’ve been asked this question so many times over the years (D&C vs Full documentation).

There is no clear best way to document a project. It always comes down to the individuals, either on the consulting team or the D&C team. See also my post on competitions.

I have seen a trend towards the D&C approach.

The typical pros are:

  • It’s cheaper (cuts out the consultant)
  • Full responsibility lies with the contractor and it was always going to.

The typical conns are:

  • A perception you will be ripped off
  • D&C design isn’t as good.
  • Full documentation means there are ‘no variations’.
  • The building may be too far down the track when the D&C contractor is appointed.

Are Consultants Creating the D&C approach?

My call is yes. There is a definite move to providing less in consultant documentation. Two classic examples are shown below.

E.g. 1: Its easier (Time wise, PI insurance etc) to not show balancing dampers on a drawing or commissioning valves and so on. Just put a note on the drawing or in the specification and let the contractor work it out.

Eg. 2: Co-ordination, will it fit? Let the contractor work it out attitude often pervades.

So, if the consultant is providing a concept design and in reality a schematic layout, you can see why industry groups think “I might as well just use the contractor”.

In the consultants defence a client fees may be so low, that all you can do is dust off the last similar project and regurgitate it.

If you’re a services contractor

If you’re a contractor with the willingness to employ great staff and undertake projects in a fair and reasonable manner, then absolutely the opportunity to excel and win work without consultant input is there.

Main D&C Contractors

The large and good D&C contractors are generally forgotten in the process. They are often frustrated having to tender on documentation, which is consultant derived and can be considered useless. Wrong Concept employed, not representing best value to the client, un coordinated drawings (that just can’t work) etc are the comments you hear on that side of the fence.

What Should Consultants Be Doing

I’ve been a consultant for most of my career, so forgive me for my slight bias.

A consultant should be offering more than great drawings.  And clients should be using consultants to do more than just ‘great drawings’.

What a consultant should be doing:

  • Ascertaining what the client wants
  • Ascertain what the Architect wants
  • Ascertain what the site will allow
  • Review the world wide market and report to the team the options available, with life expectancy, power and water consumption etc. (LCC). So the client can make the best and most informed decision.
  • Concept design, spatial planning
  • Setting minimum standards.

Summary: Providing the smarts

At this point the consultant can be moved to a watching brief role or if they have the skill set move to a ‘documentation consulting’ role. For the Architects reading, this is all similar to the ‘Concept Architect’ and ‘Documenting Architect’ roles.

If a consultant provides all the services above in a watered-down fashion (due to low fees shall we say), they will not be thanked and push more work the D&C route.


I’ve sat on the fence a bit on this one, but hopefully covered off the main topic items. I have not covered PI insurance on purpose. Your feedback and experiences would be appreciated…write a comment.

Author: Jorgen Knox

Date: 12/08/2014

Contact: e: jorgenk@knoxadv.com.au, t: 02 800 33 100, w: KAE, LI