Can we dump the shop drawing stage?
Recently I’ve started questioning the level of detail required for complex buildings. A Melbourne residential tower I’ve been working on is now on site and one basement deep. The design process has been challenging, with apartment customisation continuing well into the contract. Our client offered purchasers 10 upgrade options, and for a fee, complete customisation of apartments. The resulting construction documentation contained 125 apartment variations and took on quite an organic nature.
Time and budget constraints meant that we couldn’t model every option so we developed a series of rules that defined each condition. For instance, some kitchen and bathroom elements had fixed dimensions so when they went beyond a certain range, we created a new type. Ranges were based on tile and carcass modules and appliances. We couldn’t in fact have delivered the project without this ‘grouping’ information.
The D&B contractor on the project offered our client significant cost savings through its own network. Included in its works was an extensive shop drawing and service co-ordination for all prefabricated items. Our tender drawings were used not for construction but for design intent, with mechanical, plumbing and fire services completely redrawn by the contractor’s sub trades. In addition to the consultant’s documentation, shop drawings were developed for basement piling, pool and spa, facade, lift interiors, interior elements and joinery.
The D&B process is evolving, with a significant shift away from architects and engineers as documentation creators.
The level of contractor service provision was comprehensive, relieving the architect of intense documentation. Substitutions and innovations were compared to design intent drawings, and responsibility for changes that deviated from it was with the contractor. However the only mechanism for quality control and further design iteration was through lengthy shop drawing review (the facade and bespoke joinery packages still need more iterations to resemble the design intent). The D&B process is evolving, with a significant shift away from architects and engineers as documentation creators.
In contrast, consultant roles on smaller projects appear unchanged, where architectural drawings are still used for construction. Here, I’ve worked with sub-contractors and fabricators in a direct and positive way to produce less redundant information. Could this not simply translate to a larger scale? Yes, there are efficiencies with sub-contractors documenting and building a product with which they are familiar, but the benefits of the design team’s wider project knowledge and momentum surely outweigh this.
Instead, the D&B option should begin with a development phase long enough for the design team to capture project intent without being too prescriptive. If the team was then given the opportunity to work directly with the contractor’s sub-trades, there would be no need for a shop drawing process at all. Alternatively the contractor could redirect certain documentation packages to their sub trades earlier on, to avoid producing redundant and conflicting information- cutting overall costs and time!
Alan Maclean is an architect at Bates Smart Architects in Melbourne