Analysis of the pros and cons of Single Stage Design and Build Approach and key considerations for Construction Project Managers

1. Single Stage Design and Build Method & Construction Project Management
John Constance
MSc in Project Management, University of Liverpool
Introduction
When design concept drawings are produced this indicates that a design brief has been
implemented and additional data has been prepared (RIBA 2007). The design concept
drawings include completed structural and building services systems, specifications and
the design initial cost plan.
The use of the GC/Works/1 Single Stage Design and Build methodology indicates that
the number of tenderers are restricted and narrowed down to an approved list based
derived from applicants experience, general skills, financial capacity, integrity, and their
demonstrated competence and quality assurance approach.
Considering the two factors, this paper reviews the strengths and limitations of single
stage design and build methodology and the major challenges it imposes on project
managers for construction during design work; and how these challenges and their
associated risks can be mitigated.
Design Concept Drawings
According to the USACE (2008) Engineering Guide Design manual, the design concept
comes immediately after the special consideration of function, sustainability, technical
codes and standards, construction classification, accessibility standards, site adaptation
and alternative design and recommendations are completed and approved by the client.
With this information the designer can then produce construction drawings that will
include a cover information, perspective and architectural plans including floors, fire
protection code compliance, demolition, etc. and elevations and sections. With this
information the designer can now proceed to produce intermediate plans and a final
design.
However, during this stage it is important the construction project manager ensure that
a monitoring and controlling system is in place to produce the design information (CIOB,
2010, p.44). Selecting a design team leader can do this and there should be meeting of
the design team and other consultants to review all characteristics of the project. There
should also be a design management plan to show roles and responsibilities, drawing
type size and format, and schedules, computer aided design interdependencies, an IT
data transfer system, the impact of design resources to the productivity achieved, design
changes procedure and their predictive effects, and design performance review.
Fewings (2005, p.234) advised that design management be done to ensure that building
design information be the best quality and be constructed at the right time and delivered
to the right people. This is important for the construction project manage so as to have
the design team fully prepared for the issuance of the tender.

2. GC/Works/1 Single Stage Design and Build Methodology
In the single stage design and build methodology the contractor is not involved in the
project planning at the initial stage. Therefore offers are submitted with less information,
making the firm price only as wholesome as the design information. Also, any change
undermines certainty achieved with a lump-sum tender, and if cost assessment or the
contractor’s working method is incorrect, the risk transfer may have little value, and the
tenderers will take pricing risk due to the competitive pressure, and the approach offers
reduced scope for a shared objective or for a contractor’s contribution to the design
development.
Notwithstanding, with this approach there is cost certainty, risk allocation in the contract
is well defined, pricing is competitive, the cost of tendering simplifies tendering process,
with a complete, well-documented design there is a clear delineation of design and
construction obligations, and timescales are identified creating less opportunity for
extended negotiation (Simon Rawlinson, 2008)
Challenges and associated risk mitigation measures
• Ensuring all problems are identified - this can effect in delay, design changes, co-
ordination hitches – ensure the design concept is detailed and well defined and
involves all professional disciplines early on.
• Managing the design process including co-ordination and responsibility to
produce certainty – this can lead to poor design programming and tracking and
product – thoroughly apply design-stage reviews and freezes considering cost
management procedures (Sundaram, 2008), all the elements of green design
(Kubba, 2010, p.305), value management (CIOB, 2008, p.28), and the most
technically advanced and applicable suite of construction design codes (British
Standards Institute, 2009)
• Ensuring tender documents are complete or unambiguous – this can lead to
errors or blunders in the contractor’s offer – make sure the tender documents are
in accordance to the code of procedure for single stage selective tendering
(1996, NJCC)
• Selecting the spot-on contractor – poor selection can lead to poor delivery and
unsatisfied client – invest in pre-bid conferences and mid-tender consultation
using quality criteria and maybe e-tendering software (Simon Rawlinson, 2008)
• Mitigating contractor’s risk – while this creates competitive pricing it tends to
leave the contractor’s exposure open-ended - limit the contractor’s risk and
minimise work design during construction, and permit the contractor as much
discretion over specialists selection
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References
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Chartered Institute of Building (2010) Code of practice for project management for construction and
development 4th ed. Oxford: Wiley-Blackwell

3. Fewings, P. (2005) Construction project management: an integrated approach. London: Taylor & Francis
Kubba, S. (2010) ‘Elements of green design and construction’. In: Green construction project
management and cost oversight. Oxford: Architectural Press, pp.28-70
NJCC (1996) Code of Procedure for Single Stage Selective Tendering Published for the NJCC by RIBA
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Available from: http://www.building.co.uk/data/procurement-single-stage-tendering/3127871.article
Sundaram, V. (2008) ‘Essentials of design phase cost management and budget control’, Cost
Engineering, 50 (2), pp.24-28.
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Support Center, Huntsville, Huntsville, Alabama