Project focus: Evelina Childrens Hospital, London

EA Scaffolding & Systems Limited undertook this complex scaffolding project during 2012.

The building

The Evelina hospital was founded in 1869 (as Evelina Hospital for Sick Children) by Baron Ferdinand de Rothschild, whose wife, Evelina, and their child had died in premature labour. It was established in a purpose-built hospital in Southwark Bridge Road, Southwark, opposite what was originally the headquarters of the London Fire Brigade at 94 Southwark Bridge Road. It was nationalised in 1948, becoming a branch of Guy's Hospital. In 1976 the original hospital building was closed, and the children's wards were moved to the newly built Guy's Tower. The original buildings have since been demolished, and the site is currently a green space. In 1999 a decision was made to re-establish Evelina Children's Hospital as a new specialist hospital for all children's services at Guy's & St Thomas', on the site of a former nurses' home. An architectural design competition was managed by RIBA Competitions and won by Hopkins Architects and engineers Buro Happold. Davis Langdon provided quantity surveying and employer's agent services. Construction began in 2002, and the building was completed in 2004, ready for fitting out.

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This is one of the few hospitals in the world to be built not around the doctor's perspective, but around the patient's. The building won the IStructE Award for Education or Healthcare Structures in 2006. In addition to child healthcare today the hospital contains an active school for sick children.

The problem

During 2010 problems were noticed with the double glazing units installed to the roof. The edge separating beads between the panes were becoming dislodged and were being forced towards the centre of the panel, each pane of glass of the double glazed unit was therefore free to move causing leaks and inefficiencies associated with the loss of seal between panes . Because of this a decision was made to replace all of the roof glazing.

The contract

In October 2011 Gleesons were awarded the main contract package to replace the roof glazing, specialist glazing sub-contractors Structura were appointed to undertake the glazing works. EA Scaffolding & Systems Limited were awarded the scaffolding design and installation package from Structura. The scaffold package was awarded in January 2012 for start of works during February, scaffold contract value GBP500,000.

The scaffold solution

Overview

The parabolic arched glazed roof spanning some 33m provides protection to the entire central atrium of Evelina Childrens hospital and the active school on Level 3. Removal of the high level glazing therefore presented a considerable operational challenge. It was essential that the school and hospital remain open and that persons and plant inside were protected from site activities, noise, vibration and the weather. The scaffold solution also needed to provide lifting, edge protection and insulation capabilities for the glazing operations.

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Description of the scaffolding

Following a project demand review EA Scaffolding and Systems Ltd chose to tackle this demanding project using a range of specialist scaffold equipment. OKTOLOK modular system scaffold was chosen for external scaffolds and internal birdcages, DESSA 78cm aluminium beams were chosen for all structural spans and DESSA UNI roof was chosen for the mobile gantries and temporary roof. GEDA transport platforms were used to facilitate both men and materials, specifically large glazing panels complete with bespoke shifting trolleys. The scaffold when complete consisted of the following key items:

An excess of 300 Tonnes of scaffold materials where used to complete the above works.

Design

Special requirements

Each phase of the works required independent design, certification and checking. Working to current EN legislation, EA Scaffolding and Systems Limited produced over 120 drawings detailing each aspect of the design and operation. Phase specific risk assessments and methods statements being prepared for all phases. EA Scaffolding and Systems Limited in house designers produced 3D solid models of each phase allowing the Hospital Trust to visualize and discuss the scaffold phases prior to erection.

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Analyses and checking

Due to the sensitive nature of the existing structure and the fact that a majority of the scaffolding was to be built from existing floor slabs, walkways, roof beams etc EA Scaffolding and Systems Limited's in house designers produced 2D and 3D structural analysis models in order to optimise the scaffold design in terms of self weight and to accurately model the scaffold behaviors allowing independent assessment of scaffold impacts on the existing structure. Non-linear analyses model were used extensively in order to predict the precise scaffold behaviour.

Health and Safety

Working within a live hospital environment poised many health and safety challenges. The West elevation access scaffold was to be constructed directly over the main hospital entrance, the road outside being a red route for Accident and Emergency vehicles. Internally the hospital and school were to remain operational during all scaffolding and re-glazing operations. Each pane of glass weighing in excess of 280kg was to be lifted and replaced above the live working environment. Furthermore, construction noise was to be kept to a minimum for the benefits of pupils and patients. In order to reduce the impact noise generated through the fixing of modular scaffolding, EA Scaffolding and Systems Limited noise trialed numerous hammer types and opted for a timber shafted copper core hammer for all fixing operations, this producing the least impact noise whilst maintaining impact force. As expected, full PPE was required at all times and the job was completed with no reportable incidents.

Statistics

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Runway system
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Upper roof runway
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Walkway and un sheeted roof
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Roof being moved
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Front following 1st roof move
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Roof from walkway
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Cantilever birdcage
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Unsheeted roof from front
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Brise soleil Walkways
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Underside of roof with lifting rails
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Brise soleil walkways
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School protection deck
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Brise soleil walkways
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Upper level of internal scaffold
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Atrium scaffold
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Atrium scaffold
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Atrium scaffold
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School protection deck
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School protection deck
EA Scaffolding and Systems Limited.
Unit 16 Sedgwick Road, North Luton Industrial Estate Luton LU4 9DT.
Telephone 01582-575200, Fax 01582-599254, info@eascaffolding.co.uk