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Collective on Calton Hill

Extensive refurbishment of the Category A Listed City Observatory, Transit House, Playfair Monument & Boundary Walls. Including a new restaurant, which cantilevers over the north east corner of the boundary wall, a new gallery which is excavated into the basalt mound to the north of the Observatory and a new welcome kiosk at the East Gate. The connections are carefully knitted together by a new landscaping scheme, allowing the site to become fully accessible, for the first time in its 240 year history.

 

The City Observatory was designed by W.H. Playfair in 1818. We had a full detailed set of original Playfair drawings to work with when developing the proposals. This informed the conservation work, including reinstating the original interior plan form of a single central hall with double column arrangement; opening this up allows light to flood into the space on a perfect east/west orientation as Playfair intended. A particularly striking feature are the meridian slots, two 180 degree slices into the roof and elevation of the east and west wings which were once covered by timber shutters, to allow the building to be opened up to the sky. These have been reopened, the shutter mechanism overhauled and the slots glazed as part of the works; this intervention feels very contemporary, but is a fundamental original element of the 200 year old building design.


The Transit House predates the City Observatory, and in many ways is a simplified first version, with a single meridian slot, the same timber shutter system and scaled down detailing.


The restaurant occupies the vacant north west corner of the site; historical analysis found that Robert Adam had urged James Craig to ‘fortify’ each corner of the site when he was developing proposals for Observatory House and although this was not fully realised, the later additions of the Playfair Monument and City Dome strengthened this principle, leaving the north west corner empty by contrast. The form of the restaurant is designed with a geometric kinship to the Playfair Monument, diagonally opposite. From outside the compound it appears single storey, projecting out in a bold manner over the boundary wall. A series of stone columns support the roof, set in an asymmetric arrangement to create a sense of anchoring the building backs into the hill. The pyramid roof form is topped by a glazed oculus, to echo the form of the Observatory House.

 

Material Used :
1. Structural Steel: Parkhead Welding Co Ltd
2. Internal structural: In-situ concrete and blockwork
3. Ceiling and soffit linings:  Restaurant – Bespoke joiner made ash battens over acoustic felt
4. Gallery – Sto Silent Panel A-Tec over exposed in-situ concrete soffit
5. External Walls: Self load bearing Cullalo sandstone outer leaf to gallery, restaurant and kiosk – supplied by Tradstocks. 
6. Doors: External: Schuco Aluminum Door System / Internal: Integrated Doorsets or bespoke joiner made doors to Observatory & Transit House. Ironmongery: Allgood plc
7. Windows: Schuco Aluminum Window System to new building, Sash & Case windows overhauled by Fergmann Window Solutions. 
8. Roofing Finish: Kiosk & Restaurant – VM Quartz Zinc Plus. Gallery – CetcoVolseal inverted roof. Lead roofing by D Blake & Co. 
9. Bespoke Glazed Slots &Rooflights: Grey and Dick Ltd 
10. Conservation Rooflights: The Rooflight Company
11. Sanitaryware: Ideal Standard
12. Bespoke Furniture: Elite Joinery

Floor Finishes: 
1. Oak Flooring – Russwood Solid Oak Chateau Prime Grade
2. Polished Concrete: ArdexPanDOMO K3 FloorPlus
3. Linoleum: Forbo Flooring 

Project credits

M&E consultant
Quantity Surveyor, Principle Designer, Project Managers
Landscape Architects
Acoustic Consultants

Product spec sheet

Aluminum Window System to new building, Sash & Case windows overhauled, Aluminum Door System / Internal: Integrated Doorsets or bespoke joiner made doors to Observatory & Transit House
Polished Concrete: Pan DOMO K3 Floor Plus
Silent Panel A-Tec over exposed in-situ concrete soffit
Ironmongery
Bespoke Furniture
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