User:Chia-Cheng.Ng/sandbox/Demolition of Queen Elizabeth Hospital, Hackney

The Old Queen Elizabeth Hospital for children located on Goldsmith Row, Cambridge Heath, London E2 8FU went through a regeneration/repurposing process in 2014 and was completed by 2017. The Site now stands the original mid-Victorian style building known as Charles Hayward building, together with 24 new residential blocks split onto another plot of land parallel to where the old hospital was standing.

History
The Hospital was founded in the 1860s by two sisters, Ellen and Mary Philips during the Cholera epidemic, it was named The dispensary for women and children in Virginia road and Bethnal green. The founder originally decided that this hospital should be an institution that only treats children, but the work was later transferred to the relatively small North-Eastern Hospital for Children which houses 12 hospital beds.

Three years after the opening of the initial building, they managed to acquire the freehold of the buildings on the corner of Hackney Road and Goldsmiths Row, where the hospital soon took over. Around the end of 1905 extension blocks were added to the main building, greatly expanding its capacity to house patients. Queen Elizabeth Hospital later became part of the Royal Hospital Trust (now Barts Health NHS Trust), which was then relocated to Royal London Hospital, vacating the buildings on Hackney Road in 1996. The Hospital complex was left unused and standing until 2017 when it was finally demolished.

Description of the Demolition
Demolition of all existing hospital buildings apart from the main building fronting Hackney Road. The Demolition of the hospital was awarded to Downwell work who has done multiple demolition projects with the NHS in both London and South East of the UK. Their role in the process was the principal contractor for asbestos removal and general demolition; Soft strip, extensive façade retention scheme and demolition works .Throughout the demolition operation, the job of asbestos removal was subleased to Inner City Environmental. Hiring a subcontractor who specialised in a particular trade is common and legal. In the procedure of soft stripping were completed through dismantling and categorising into their own grouping of waste before sending it down to the ground floor by the way of internal steel frame lift shafts .The demolition were done through the use of a high reach machine under the strict guideline of NFDC. According to the given report, no major incidents were reported in the duration of work.  { "type": "FeatureCollection", "features": [ {     "type": "Feature", "properties": {}, "geometry": { "type": "Point", "coordinates": [ -0.06591260433197023,         51.53142304158591        ]      }    }  ] }

Surveying

 * Building Surveying


 * 1) Type of Construction material.
 * 2) Previous Stage.
 * 3) The presence of hazardous materials.
 * 4) The condition of drainage and underlying problems with water pollution, flooding and erosion.
 * 5) Shared utilities and facilities.
 * 6) Adjoining vehicular and traffic conditions.
 * 7) The impact of noise, dust, vibration and traffic movements on the local community.


 * Structural Surveying


 * 1) Construction Method
 * 2) The fundamental Conditions of basements and underground tanks
 * 3) The Skeletal system was adopted
 * 4) The building condition

Removal of Hazardous materials
What is Asbestos?

Asbestos, a common export from countries such as Brazil, Russia, South Africa and China, is a natural fibrous mineral often used as construction material from the 1950s to the ’80s. This mineral was such an accepted and welcome material in western countries, due to the fact that they have many characteristics that benefited and counter the weather; they are very strong, heat-resistant, incombustible and sound-absorbent.

In the context of the United Kingdom, buildings that were redeveloped and constructed during 2000 will most likely contain Asbestos. However, with the increasing number of lung diseases amongst the workers dealing with material, the UK has decided to ban it for health and safety concerns. That being said, Asbestos can still commonly be found in less developed countries such as India, China, Russia and Indonesia.

Sublease of Asbestos removal work

Downwell works closely with Inner City Environment through an agreement of subleasing a certain area of the Asbestos removal process, this is to ensure only qualified and well-knowledge professionals are deployed to the site by rules and regulation.

Demolition Plans
A demolition plan illustrates the different processes involved, and they are:
 * 1) Location of the building
 * 2) The distances from adjacent buildings, roads, Structures and schools
 * 3) The structural support
 * 4) Method statements for demolition of the building; Method and sequence of demolition.
 * 5) A health and safety plan for the public
 * 6) Waste Management plan
 * 7) Programme of the demolition process

Safety measures during Demolition of Buildings
All personnel on-site have to adhere to the rules and regulations, also a mandatory site induction is required. Fire and emergency safety plans are prepared and have to be shown during the induction period. Other than the standard minimizing and monitoring the onsite situation, all workforce has to wear appropriate attire when entering the site (full PPE), regular health check is also a must for all working on the project.

Demolition Methods
There are two types of demolition methods that companies employed

(1) Non-Explosive or Controlled Demolition

This process will only use hand tools and machinery and also includes the electric excavators operated from a distance.

Type of Demolition within this category-


 * Soft Strip
 * Floor Coverings
 * Suspended ceilings
 * Partitions
 * Doors
 * Air conditioning
 * Heating
 * Lift Removal
 * External cladding
 * Windows
 * Water Tank removal
 * Demolition using standard or High-reach excavators
 * This method of demolition depends on the height of the buildings which dictate the type of machine used in the process. When a building is taller than three storeys, high-reach excavators are normally used. Once Demolition reaches the lower floor, standard excavators will come into play.
 * Top-Down Demolition
 * While in some situations when the building set for demolition is surrounded by listed buildings, Demolition companies will go with the top-down method. All side of the building is covered with monarflex and scaffolding which helps in reducing dust during work.  “Small excavators and skids steers (Bob Cats) are lifted onto the roof by cranes. Openings made in the roof allow the construction of ramps. These allow excavators to go down onto the floor below. The excavators will then remove the roof working from below and above under controlled conditions. The same process follows on for each floor and with waste materials removed using waste chutes, lift shafts or materials craned away in skips.” (7)
 * Destruction
 * This process takes place using a crane. The panels are removed from the main building in reverse order of construction, although this method can only take place with proper support such as propping to prevent any potential disaster such as collapsing.
 * Dismantling
 * This is rather simple as compared to all others. Old machinery from the building is taken out of the building and dismantled (most of the time cut into small pieces).

(2) Explosive Demolition

Type of Demolition under this category


 * Implosion Method
 * Demolition through explosives through the removal of the foundations. This is typically used to demolish large industrial buildings and public infrastructure (power stations etc.). Most buildings demolition in the city is carried out by conventional means.  This method focuses on the supporting element of the building such as the column and the floor slab and fixes explosives on them. Once detonated, the entire structure will collapse.
 * "Falling like a tree"
 * Similar to the name of the explosion, the building block falls towards the side like a tree. This will be the preferred method of demolition works when there is sufficient space around the falling building.
 * "Falling into its footprint"
 * As for this method instead of falling to the side, it is downwards that the building is crushing towards. Different from “Falling like a tree”, “Falling into its footprint” is used when there is limited space around the building.  When planting the explosive, engineers will mainly focus on the middle section of the building block where the weak point is. This is to help the upper floor to carry enough momentum to come crashing down onto the middle breaking point after the explosion, at the end all falling on its footprint.

Façade Retention
The nature of the work is to retain the façade of an often historical building with great importance. Keeping the façade, preserving the exterior look while letting the redesign of interior space and structure meet modern standards.

For the reason of the work, the Designer/ Architects has to do extensive studies to calculate the estimated price of the project. During the demolition, façade structures are supported with an internal layout system when all of the internal work is done it will be reconnected with the building façade.


 * Façade Retention Type
 * Scaffolding (Suitable for low storey building with space at the base)
 * Proprietary rentention for higher facades
 * A mixture of both

Regardless of the support system. It must be able to withstand excessive force during work to prevent cracking on the façade, the supporting system has to resist the overturning moment and also eccentric dead load, in some cases, Kentledges can be incorporated to counter these moments. According to the information given by Downwell. 96 per cent of its materials from the site were recycled for future demolition.