Performance specifications are an essential part of design and construction documentation.
By Lood Welgemoed, Boogertman + Partners
Having spent most of my working career in the United Kingdom, I was at first surprised and then worried when I found that South African architects don’t generally use performance specifications. For me this was an essential part of the design and construction documentation and a safety net which no office can afford not to have.
It seemed that the basic product selection was being done by the architect, but this was then captured and slightly expanded on in the bill of quantities (BOQ) by the quantity surveyor. The problem with this is threefold:
1. Firstly, the BOQ does not describe product or system performance and installation guidance, other than perhaps a reference to the model preambles.
2. Secondly, with respect to the quantity surveyors, they do not carry indemnity insurance and won’t be held responsible for any errors in specification.
3. Thirdly, there is a greater onus on the architect to manually add product descriptions on drawings, giving rise to duplication and error.
This problem does not appear to affect the engineering disciplines as much, which tend to produce comprehensive specifications. Perhaps it is as a result of the fact that they are also responsible for producing their own bills of quantities, again somewhat unique to South Africa.
Happily now this is a thing of the past at Boogertman + Partners, where Brit expatriate John Chapman has been appointed as lead specification writer for the group. John has been using the UK NBS (National Building Specification) system to develop a companywide master specification which forms the basis of each project specification.
This is a very comprehensive and current document which describes not only the product, but also relevant codes and regulations, approved suppliers, performance requirements, installation methodology and quality assurance.
From this master specification, a detailed project specification is created for each project alongside the architect and interior architect, by way of eliminating unnecessary clauses and adding project-specific products or systems. The master specification is divided into elemental categories such as metalwork or ceilings/partitions/raised access flooring or tiling.
The main advantage of the master specification is that ambiguity is avoided and the specification is constantly updated with changing building codes, green building requirements, new or discontinued products and feedback from projects. Through this collective approach the master specification is imbued with the experience, knowledge and character of the entire practice.
Contractually the specification takes priority over drawings, giving the architect and the client recourse in case of poor workmanship or inferior product selection by the contractor.
Leading on from this, the project specification is cross-referenced on the drawings by using keynotes. These are short codes which are annotated or tagged onto building elements in plan, section and elevation, eliminating the need for long descriptions and potential errors. With building information modelling (BIM) becoming more the rule than the exception in our office, the next development is to have the specification keynotes embedded into intelligent building components so that the keynote appears automatically when the item is tagged on a drawing.
In conclusion, the last few years have seen the arrival of comprehensive project specifications at Boogertman + Partners, at first with some trepidation but gradually being embraced as the architects recognise their value. Hopefully this will become an industry-wide trend.
Boogertman + Partners
Tel: 012 429 7300