Cost of Curvaceous Work

The popularity of “blobitechture” as practised by Hadid, Gehry etc. has led to a rash of offshore façade and interior finish subcontracting, some successes and some very disappointing results. The atmosphere of panic is often the result of AEC professionals who are shocked to find how much it will cost to build a beloved but curvaceous project. Unless a “perfect fit” supplier is missing from the bidders list, the bids received will closely reflect the productivity of existing technology, the market cost of materials and the current cost of labour. This means that the sticker shock is most often due to a lack of appreciation of the cost of design decisions related to processing labour, not materials.

In the following article I focus on exterior and interior paneling and cladding and provide a guide for comparing the cost of various categories of curvaceous work, based on the relative difficulty of the detailing, fabrication and installation process. I hope that this information will be useful in making choices during the design phase regarding materials, tolerances, geometry and ease of installation.

Because most suitable raw material is supplied in linear or planar form, such as sheets and stock lengths which must be laid out, cut, possibly formed and then assembled, geometric complexity (especially with a lack of repetition) is one of the biggest cost drivers in custom work. Materials like fiberglass and glass, which can be made in to compound curves, but which have no form until processed, are also costly to use. This is because molds are required and they are expensive to design and build. This problem is particularly acute if there is little or no repetition, as with Hadid’s glass-wrapped cable-car terminal in Austria.

And finally, don’t forget the cost of multiples, which arises in the pricing of mundane but custom components like screen segments, store fixture hooks, lighting shrouds, handrail brackets, machined trims, etc. These might only cost $50 each, but if 2000 are required, they suddenly become a major item. The multiple trap came in to sharp focus on a special effects job years ago, but the problem was with watts and dollars. A production company commissioned a friend of mine to build a full size mock-up of a pocket coil bed to be used in filming a commercial. Each coil had a light bulb in it and the lighting technician thought he needed 3kw to power the bed. Unfortunately he was off by a factor of ten and the bed sucked up 30kw of power, which was a lot more than they had available. My friend called me up in a panic and we spent the next 12 hours re-wiring the prop and running cords out the windows and all over the building; then we stood by with fire extinguishers in case the crew left the bed on for more than 30 seconds at a time.

Following is a list of panelized work organized by varying degrees of geometric complexity with the addition of explanatory notes. 1 is the lowest cost category, while 10 is the highest. Like the Dewey Decimal System, spaces have been left for the addition of intermediate categories. Please note that this system does not take in to account the cost of the material itself, which is relatively easy to determine. If you are in the design phase of a project, the object is to chose the fabrication option furthest up the list that will still provide the impact you want to achieve.