The building sits on an outcrop of a small rocky headland rising about 15 m above the sea on the narrow western coastal margin of Loch Fyne. Access is along a low coastal strip on an unsurfaced single-track road.
The initial concept was to replace a derelict traditional wooden summer house which sat upon the summit of the headland with a modern single storey building approximately 8 m long x 4 m wide, having modern amenities in the form of basic sanitation, sleeping accommodation for a couple, and a study desk/reading area. The building was to be designed to maximise the stunning views across Loch Fyne while withstanding the rigours of the local environment for many years to come.
Early proposals for the project consisted of an anvil-like reinforced concrete substructure, supporting a superstructure comprising glass external walls surrounding a small braced steel core topped by an aluminium stressed-skin monocoque roof.
Unfortunately, the design was found to be both expensive and difficult to construct in the location. Further iterations resulted in the final solution that featured a slender tubular steel substructure supported on an elongated pad footing dowelled into a shelf cut in the bedrock, and a relatively traditional timber roof.
These changes required further consideration of the superstructure, in particular the sway and torsional forces present in the core required to be transmitted to ground. The new proposal also had superior environmental credentials since the volume of substructure concrete was reduced, with a further indirect but relevant benefit of less potential for pollution on site.
Costing of this proposal proved positive, but concerns remained over the buildability and future maintenance of the building, particularly regarding installing and replacing glass units, but also with respect to the amount of work still required at height. As a result, glass and galvanized steel play a major role for the long-term durability of the structure.
Opportunities to introduce significant temporary or permanent torsional stiffness in the thin floor deck of the superstructure were limited, so detailed modelling of the superstructure’s distortion as it was slid out along the rails was undertaken.
When the steelwork was erected slight distortion of the rails due to galvanizing was found relative to the deflection tolerance of the glazing. Trial slides of the structure to check that this was not going to damage the glass when the finished structure were carried out. The first slide was carried out with kentledge applied to the superstructure’s floor deck to mimic the substantial weight of the double glazing and the floor and roof finishes. Distortion of the floor deck edge was monitored throughout the slide and the results were satisfactory.
A second successful slide was then carried out with the glazing mounted. Great care and attention to detail has resulted in an elegant, efficient and long-term solution that accounts for limited site access and an aggressive environment.
Image: Tigerchick Media