Hapimag, Lancaster Gate, London

Client: Hapimag Investments (Guernsey)

Value: £14.5M (Approxl)

An interesting refurbishment project in a listed building with fine façades and a number of outstanding historical features. Originally bult as three large high standard houses on a corner site, just north of Hyde Park, it was converted to multiple occupancy as a hostel/hotel and an Aparthotel more recently. The 130 year old building has a basement and five floors, with mansard roof space and an additional floor added in part. Our involvement included the following services:-

Land and Building Surveying:

Topographic site measurement, drain condition survey;

Geo-Environmental Engineering:

Soils / contamination and foundations investigation;

Structural Engineering Design:

Survey, building refurbishment and mezzanine designs;

Civil Engineering Design:

External works including rear courtyard and pavement.

The original building construction was predominantly load bearing masonry with massive solid walls and traditional corbelled brickwork foundations, and a concrete basement slab onto the underlying London Clay. The suspended ground floor was supported on early rolled iron joists, with dry stone aggregate lime infill known as Holland & Barrett flooring, as an early non combustible floor system. The remaining superstructure was largely separate floor and ceiling joists supported on primary timber beams which were supported on rolled iron beams, with some modern steel beams that were installed after fire damage.

The building refurbishment comprised a mixture of existing masonry alterations and new steel frame mezzanine structures, supported off new steel and existing timber floor supports. The large ground and first floor ceiling heights enabled sleeping pods to be installed on mezzanines above integrated kitchen and bathroom areas, but retaining full height living space to the external facades. This complex integration of new hospitality services and expectations, within original and listed building features, needed sensitive architecture with well considered structural solutions to be integrated.

Part of the challenge involved enabling the upgrade and installation of modern services, maintaining the original ceilings and plasterwork across the site. The drainage design and detailing was of particular complexity, as historic records were not complete and on site surveys were necessary.

Apart from ourselves, the main project team consisted of a number of disciplines, as follows:-

Client:

Hapimag Management UK Ltd

Project Manager:

Orchard Property Development

Architect:

Howse Wallis Partnership

Quantity Surveyors:

Optimorph Developments Ltd

Civil & Structural Engineers:

Evans & Langford LLP

Mechanical & Electrical Engineers:

Mendick Waring Ltd

Principal Contractor:

Interserve/Paragon