was006-002: demolition exemplar case study … house full case...was006-002: demolition exemplar...

WAS006-002: Demolition Exemplar Case Study

Recycling Demolition Arisings at Hamilton House, Sandwell

By a strong collaborative partnership, more than 96% of the demolition arisings were recycled, exceeding the 70% recycling target for the project.

Project code: WAS006-002 ISBN: 1-84405-363-6 Research date: November 2006 - April 2007 Date: May 2007

Front cover photograph: Hamilton House, in Sandwell prior to demolition works beginning.

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Recycling Demolition Arisings at Hamilton House, Sandwell 1

Executive summary Sandwell Metropolitan Borough Council commissioned Coleman & Company Ltd, as the demolition contractor, to demolish a 24 storey high rise residential block, Hamilton House, with associated area, car park and footpaths in Sandwell near the centre of Birmingham. This was carried out as part of a 5 year partnership contract between demolition contractor and the local council. The demolition methodology involved soft stripping and controlled explosive demolition. Demolished materials were source segregated and sent to nearby recycling facilities including the Coleman Meriden quarry for the crushing and screening of inert materials. A high recycling rate of 96.3% was achieved for the project. This high recycling rate was attributed to a long term partnership contract approach, mutual trust, an open relationship and team work reinforced with agreed sustainability objectives and technical experience. The partnership approach to long term contracts helps to save costs and liability to the client, provide a safe environment for the local residents, improve on the design of programmes for the contractor, and increase on quality of resources to achieve high recycling targets. Furthermore, these factors helped overcome perceived barriers associated with traditional tendering, limited project planning, cost and programme.


Contents 1.0 Introduction ............................................................................................................................. 3 2.0 KEY FACTS: The Sandwell and Coleman Partnership at Hamilton House ................................ 3 3.0 Project Details.......................................................................................................................... 3 4.0 The Sandwell and Coleman Demolition Partnership Contract ................................................. 4

4.1 Reasons for the partnership ...................................................................................................4 4.2 The tendering process for the partnership contract..................................................................4 4.3 Partnership Working Arrangements.........................................................................................4 4.4 Strategic Management ...........................................................................................................5

5.0 Project Planning....................................................................................................................... 5 5.1 Early Contractor Involvement through the partnership .............................................................5 5.2 Achievable Recycling Targets .................................................................................................5 5.3 Site Waste Management Plans................................................................................................6

6.0 Demolition works ..................................................................................................................... 6 7.0 Reuse and Recycling Activities................................................................................................. 7

7.1 Recovery and Recycling of Materials .......................................................................................7 8.0 Recycling Rates........................................................................................................................ 9 9.0 Drivers and Barriers to Recycling........................................................................................... 10 10.0 Environmental and Social Considerations.............................................................................. 10

10.1 Transportation.....................................................................................................................11 10.2 Climate Change Considerations ............................................................................................11 10.3 Socio-Economic Considerations.............................................................................................11 10.4 Health and Safety................................................................................................................11

11.0 Project successes and future improvements ......................................................................... 12 12.0 Further Information ............................................................................................................... 12


1.0 Introduction Coleman & Company Ltd (Coleman) was commissioned by Sandwell Metropolitan Borough Council (SMBC) to demolish a 24 storey high rise residential block, Hamilton House, Smethwick, Sandwell, West Midlands. Hamilton House was scheduled for demolition by SMBC as part of a 4 to 5 year partnership contract. This partnership contract, worth between £4 million and £16 million, was formed on the back of a successful pilot partnership. The demolition of Hamilton House included the clearing of the associated car park and footpaths which covered an estimated 6,800 m2 in total. SMBC has not yet decided on the future use of the site once cleared. At the time of writing, the demolition of the high rise tower block was completed with only the clearance of hardcore material from the site, the car park and associated footpath remaining. 2.0 KEY FACTS

This project forms part of the 4 to 5 year contract worth between £4 million and £16 million for the Sandwell

and Coleman demolition partnership;

£1.5 million programme for Hamilton House involving asbestos removal, engineering, demolition, pre-planning

and evacuation process. The evacuation process to clear the area surrounding involves the police, fire

brigade and other standby emergency services;

24 storey high rise residential tower block demolished in Smethwick, Sandwell, West Midlands to make way

for a new redevelopment;

Demolition works were carried out near other residential housing;

The Sandwell and Coleman demolition partnership approach was the key to the success of the project;

Sustainability targets including recycling rates and waste segregation were integrated into the 4 to 5 year

partnership contract; and

96.3% of the demolition waste from the site was reused and recycled.

3.0 Project Details Coleman, an independent company, was appointed by SMBC to carry out a demolition project at Hamilton House, Smethwick, Sandwell, West Midlands as part of a 4 to 5 year partnership contract. The project comprised of the controlled demolition of a 24 storey high rise residential tower block, Hamilton House, and the removal of the associated car park and footpaths at Grove Lane, Smethwick in the Metropolitan Borough of Sandwell in the West Midlands. The total floor area of Hamilton House covered 575 m2 and the total site area including the car park and footpaths covered 6,800 m2.

Client: SMBC

Main Contractor: Coleman

Demolition Contractor: Coleman

Recycling Contractor: Coleman

The £1.5 million project involved the design, asbestos removal, demolition, excavation and site clearance of the site. No redevelopment of the site has yet been planned. SMBC will make decisions on the future of the site once the demolition project has been completed. £1.2 million of the project was attributed to the demolition works and the remaining £300K of the project was attributed to engineering fees, policing and evacuation during the controlled demolition process. The evaluation process included the involvement of fire, police and emergency services to ensure the safety of the population and maintain a clear area surrounding the site during the explosive demolition. The demolition project commenced on 14 August 2006 and is expected to finish in mid May 2007. Approximately 6 months of pre-planning occurred prior to the commencement of the on-site demolition works. This case study summarises the recycling activities of the demolition works.


4.0 The Sandwell and Coleman Demolition Partnership Contract Coleman was appointed by SMBC to undertake a pilot demolition partnership contract worth £3 million over 2 years. The pilot partnership was completed within 18 months and the value was increased to £3.8 million. As a result of the success of this pilot partnership, SMBC decided to pursue another partnership for demolition but on a larger scale. The Demolition Partnership predominantly consists of the Council’s demolition engineering team (who operate from within the Urban Design section of SMBC) and a team of managers from Coleman. Urban Design is a multi-disciplined section of SMBC comprising Architects, Structural Engineers and Landscape Architects. The demolition team is part of the structural engineering section. Urban Design regularly wins local and national awards for a wide spectrum of works. 4.1 Reasons for the partnership In order to understand the impact of SMBC’s Demolition Partnership, its benefits over traditional competitive tendering must be considered. According to the construction and demolition industry, it is widely accepted that competitive tendering is adversary, and leads to poor performance and wasted resources. Generally, the contractor is not given sufficient time to prepare his tender. This tends to lead to disputes and claims which require increased effort. Standards are often reduced and thus recycling opportunities are not fully considered. The traditional tendering process is lengthy and inflexible and vacant premises are left leaving the client with potentially dangerous premises attracting additional costs and liability. The advantages of the partnering approach over traditional tendering processes can be summarised as follows:

It replaces co-operation for adversarial attitudes by creating incentives so that all parties benefit;

It encourages teamwork between the Client, Design Team and Contractor;

It promotes continuous improvement;

It readily accepts new and innovative ideas;

It develops trust and mutual benefit; and

It forms long term relationships/contracts.

4.2 The tendering process for the partnership contract The full partnership was proposed by SMBC for £4 million to £16 million over 4 to 5 years. Due to the value of this partnership a European Commission's 'Official Journal of the European Union' (OJEU) (formerly known as 'OJEC') notice was required. Sixteen questionnaires were returned and after assessment, these were reduced to 4. The 4 successful contractors were invited to tender and attend an interview. Following the interviews the contractors and their submission documentation were appraised using a stringent evaluation process. The evaluation process carried the following weighting: 60% for quality and 40% for pricing. Following the selection and evaluation process, Coleman was appointed as the SMBC partner for a £4 million to £16 million contract over an estimated 4 years with an option to extend for a further year. 4.3 Partnership Working Arrangements The Sandwell and Coleman Demolition Partnership has a mirrored organisational structure with clear roles and responsibilities. Offices and computer equipment are shared so that all project management and partnership documentation is readily available to the team. The project core group comprises of a project manager from Coleman and a demolition engineer from SMBC. This project core group deals with the day to day affairs with regards to project delivery, client liaison and health and safety matters. Monthly meetings are held to discuss projects, programme of works, monitor costs, prepare valuations and implement improvement measures. This stable team and culture of sharing offices and computer equipment has helped to establish a good working relationship between contract partners.


4.4 Strategic Management The Partnership is committed to a range of sustainability objectives, in order to establish a good working relationship between partners by addressing the following targets:

shared delivery of service;

flexible and effective resource capabilities;

creating jobs;

strategic management;

measurement of key performance indicators (KPI);

reduction of anti-social behaviour associated with vacant sites; and

reduction of fossil fuel use.

The KPI targets for partnership projects are:

Cost predictability – 70%

Time predictability – 85%

Quality predictability – 90%

Customer Satisfaction - not confirmed

Recycling – 70%

Think Local – 96%

Material resources are recovered and/or recycled through means of the KPI targets of the project and the partnership aims to think locally and take environmental impacts into consideration when deciding on where to send the materials. In order to develop collaborative sustainability commitments, the partnership aims to save costs, reduce administration and improve programme, working relationships, workflow and design. 5.0 Project Planning 5.1 Early Contractor Involvement through the partnership Project planning for the demolition works started long before Hamilton House was scheduled for demolition. Approximately 6 months of project pre-planning took place before the building was demolished. During this time monthly co-ordination meetings were held with the housing department, traffic engineers, social services, the police, fire, emergency services, SMBC and Coleman. The method of demolition used at Hamilton House was by controlled explosives. All demolition projects carried out by Coleman require a feasibility study and report. This feasibility study is carried out to determine and recommend the method of demolition. The project core team worked in collaboration to plan and design the demolition works and incorporate optimum recycling opportunities in order to meet the KPI target of 70% for recycling. The good working relationship and mutual trust between client and contractor allowed the partnership to identify and agree challenging but achievable recycling targets. The partnership approach to demolition projects in SMBC and strong mutual trust were key factors in achieving optimum recycling rates 5.2 Achievable Recycling Targets The overall recycling target for the partnership contract for demolition waste was originally 70%. The partnership approach has been so successful that an average of 87.1% recycling rate has been achieved on demolition projects within the partnership scheme to date. The partnership does not quantify or record what is to be recycled or achieved for each project, rather a minimum of 70% recycling target is set for all projects. However, the setting of recycling targets for each project


has been discussed by the project core group and the partnership intends to implement an appropriate procedure in future. The partnership is currently achieving over 94% recycling for this demolition project comprising explosives demolition of high rise buildings; and despite an excessive amount of asbestos present within the buildings on this specific project, a recycling rate of more than 96% was achieved for this project. 5.3 Site Waste Management Plans Although a Site Waste Management Plan (SWMP) was not used, the recycling of waste from the site was optimised by the use of the established partnership approach and KPIs. Further details on the approach are detailed in Section 4.0 above. 6.0 Demolition works The demolition was carried out using controlled explosives. Twenty-four weeks of asbestos removal took place at the Hamilton House tower block, sixteen weeks of which ran concurrently with the soft-stripping removal of soft furnishings from the interior of the building. Strengthening works were undertaken prior to the controlled explosive demolition. This strengthening was unique to this project, and was required in certain locations of the building to then enable subsequent pre-weakening works to be undertaken. Preweakening of the building prior to explosive demolition involves the removal of structural elements and minimises the amount of explosives required to demolish the building. After preweakening, charge holes were drilled, explosives placed and primary and secondary protection fixed to the building in preparation of the “blow down”.

Figure 1: Charging of explosives in strengthened structures at Hamilton House

Figure 2: Secondary blast protection using geo-composite liner on every fifth level of Hamilton House


Approximately 1,000 local residents were evacuated from the area by SMBC’s evacuation team and emergency services were put into place. The controlled explosive demolition was followed by “civilising the debris pile” which involves the use of machines immediately after the “blow down” to ensure that the demolished pile of rubble is safe, before allowing residents back into the area immediately surrounding the site.

The mechanical processing of the materials by excavators was the final process of the demolition works. This explosive demolition method allows the quick, safe and controlled demolition of high rise buildings. It prevents antisocial behaviour in the area by quickly removing a building which could normally be subject to vandalism, arson and theft. The demand for old construction materials such as roof slates has increased and many of SMBC’s Compulsory Purchase Order target sites are sought out by organised gangs who systematically strip the buildings of all valuable assets. More recently buildings awaiting demolition are targeted for copper pipe and boilers. Generally all derelict buildings are a potential target for arsonists and anti social behaviour. Traditional tendering processes and the Councils’ Standing Orders are inflexible in the options available to engineers to deal with these problems that controlled explosive demolition and the partnership approach help overcome. 7.0 Reuse and Recycling Activities The clearing of materials from the site began with 24 weeks of asbestos removal to an appropriately licensed landfill site. The resulting large quantities of asbestos from the site had little effect on the attainment of over 96% recycling rate of demolished materials for the project, because asbestos is light and the recycling percentage is based on weight. Some of the soft stripped material from the site such as, carpets, general waste and some furniture was sent to the SITA landfill site at Packington. These materials were sent for landfilling since they held no value for recycling. 7.1 Recovery and Recycling of Materials Soft stripped materials such as wood were recycled locally and metal was sent to a nearby scrap metal merchant for recycling. Upon completion of the soft strip operation the superstructure remains comprising of brick and concrete. The principle aim of the “blow down” (i.e. actual explosion) is to collapse the superstructure safely into a manageable rubble pile to enable excavators to process and segregate the reinforcement bar from the concrete and brick

Figure 3: Controlled explosive demolition of Hamilton House high rise residential tower in Sandwell


work. The piles of metal waste were sent to scrap metal merchants for recycling and the concrete and brick waste transported to the Meriden quarry owned and operated by Coleman 16.5 miles away from the demolition site.

The Meriden quarry is a 27 acre site, 16.5 miles from the demolition site, that provides an outlet for the recycling of materials arising from Coleman demolition and excavation projects. Bulk quantities of materials are sorted, segregated and processed into varying classifications of construction certified aggregates. The site crushes and screens aggregates to form the following specification of materials for resale: 6F1-4 inc, Type 1 & 2, 6C, 6N, topsoil and sand. The facility recycles 250,000 tonnes per annum.

There are no plans for redevelopment works at the Hamilton House site at present and it is therefore only intended to recycle materials for backfilling of voids once the substructure has been removed. All materials crushed and screened at the Meriden quarry will be used for other Sandwell and Coleman partnership reconstruction projects. The car park and foot paths immediately surrounding Hamilton House will also be removed and processed at the Meriden quarry. When the entire site is cleared it will be covered with a layer of top soil from the Meriden quarry.

Figure 4: Mechanical processing of material by excavators at the site following the controlled explosive demolition

Figure 5: Coleman’s Meriden quarry used to crush hardcore from the demolition site


8.0 Recycling Rates The monthly project meeting provided regular feedback on the recycling values and updates to the project core group. These were based on Waste Transfer Notes (WTNs), which record the types, quantities and destinations for waste materials from the site. Recycling rates were calculated using information on the tonnages sent to particular facilities or markets.

A 96.3% recycling rate was achieved for the project; this was slightly higher than the 94% achieved from similar previous partnership projects. All timber from soft stripping was reused off-site and all metal was sent to scrap metal merchants for recycling. All hardcore concrete and brick work was sent to the Meriden quarry for crushing, screening and reuse at other Sandwell and Coleman partnership reconstruction sites. Some foundation materials from the site will be reused for backfilling at the site and the site will be covered with a layer of top soil. The remaining 3.7 % of demolition arisings from the site consisting of asbestos, carpets and general waste was sent to landfill.

Figure 7: the percentage of materials recycled compared to that landfilled from Hamilton House demolition site.

Figure 6: Breakdown of materials recycled to achieve the 96.3% recycling rate.

96.3% Recycled

3.7% Landfilled

0.3 % Lead iron

1.1% Rebar

1.4% Aggregate

54.7 % Concrete

0.1 % Mixed sheet

0.5% Scrap metal

42% Hardcore

Aggregate

Concrete

Hardcore

Lead iron

Mixed sheet

Rebar

Scrap metal


9.0 Drivers and Barriers to Recycling The underlying drivers for recycling are:

the aims and objectives of the Sandwell and Coleman partnership to achieve KPIs and high recycling rates

(detailed in Section 4.1 above);

the immediate soft stripping and removal off-site for recycling;

quick demolition of entire high rise building consisting of only brick and concrete material reinforced with

metal bars by controlled explosion;

immediate source segregation of metal from hardcore and removal off-site to nearby recycling facilities and

Meriden quarry;

cost saving of the Coleman quality scheme; and

the financial value of secondary material resources.

The technical expertise, past working relationship through the partnership approach, collaborative approach adopted by the project partners, and quick demolition process played key roles in unlocking the recycling potential of the project. The only barrier to the recycling initiative of this project was the high quantity of asbestos present at the site. Other waste materials such as glass and unplasticised poly vinyl chloride (UPVC) were sent to landfill due to the lack of recycling facilities capable of processing these materials. Coleman and SMBC have a good knowledge of the local market and understand the viability of recycling valuable materials which is built into the primary objectives of the partnership contract. The more than 96% recycling rate represented an optimum recycling achievement considering the large quantities of asbestos at the site. Asbestos cannot be recycled and therefore recycling rates could not have been improved. Optimum value was obtained from the demolition materials to achieve the maximum economic and practical viability of the initiative. 10.0 Environmental and Social Considerations Coleman operates according to an Environmental Management System (EMS) and Environmental Policy. The primary aim of the Environmental Policy is to “promote and maintain a high level of environmental performance and to operate and implement safe working methods and practices”. Coleman’s EMS and Environmental Policy, coupled with the core principles and requirements of the partnership approach to undertake projects in a way that protects the environment and its local residents help to continuously improve programmes and shape the way that waste is managed in the construction industry. A key challenge for demolition projects in the West Midlands is to carry out the demolition works close to local residents in the most effective method to prevent traffic congestion, nuisances associated with such works, keep local residents safe by keeping antisocial behaviour at bay and carrying out the works in a quick safe manner whilst minimising costs and potential liability to the council. By adopting the method of controlled explosive

Figure 8: Source segregated scrap metal pile in the foreground to be placed in the skip in the background ready for removal and recycling from the Hamilton House demolition site


demolition, Coleman was able to control risks and manage the demolition without harm to human health and the environment. 10.1 Transportation Traffic congestion near central Birmingham is unavoidable. The use of the local Meriden quarry by Coleman vehicles only, for all inert material ensured that minimal inconvenience to the local traffic was caused. The use of predominantly motorway haulage routes minimised traffic disturbance on local minor roads whilst reducing fuel consumption and minimising emissions. Furthermore, only local recyclers were used for the wood and metal, and a local landfill site in Packington for the general waste and asbestos waste, in order to keep traffic at a minimum. 10.2 Climate Change Considerations Whilst this project did not measure overall CO2 consumption, the principles of energy efficiency are incorporated in all Sandwell and Coleman partnership projects. A temporary electricity supply, rather than permanent on-site generators, was used as and when required. In addition, the use of local markets for recycling materials indirectly reduces CO2 emissions by substituting the use and transportation of non-local virgin materials. 10.3 Socio-Economic Considerations Nearby residents and local businesses needed to be protected from potential adverse impacts of the explosive demolition work. Coleman carries out a feasibility study prior to the commencement of any works for all explosive demolition partnership projects. This is done in order to recommend the method of demolition and determine the safest method of demolition that results in minimal nuisance to the local residents and services in the area. In addition monthly coordination meetings with the police, fire, emergency services, housing department, traffic and social services, demolition contractor and SMBC monitor and report on the socio-economic impacts of the demolition works. The controlled explosive demolition method results in a short term noise and dust nuisance on the day of the actual explosion; however, it causes less long term noise and dust nuisance to local residents than any other traditional demolition methods. The only inconvenience caused to residents is on the day of the “blow down”, when the area is evacuated; SMBC’s evacuation team, SMBC engineers’ Colemans and the police ensured that the area was secured and vacated before demolition, and ensured it was safe prior to allowing the local residents back into the area. After the controlled demolition works was undertaken, feedback at the monthly meetings showed that most of the local residents were impressed with the quick and smooth manner in which the explosion was carried out. 10.4 Health and Safety Significant efforts have been made in recent years to improve health and safety performance within the construction sector. Demolition contractors, like any construction industry contractors, must comply with stringent health and safety legislation and practice, and the health and safety of both site operatives and the public are a priority.

Figure 9: Proximity of Hamilton House to local residential buildings and businesses in central Birmingham


Coleman are members of the National Federation of Demolition Contractors (NFDC). NFDC contributed to the development of BS6187 Code of Practice for Demolition, the HSE Guidance Notes GS29 ‘Health and Safety in Demolition Work’ and the Certification of Competence Scheme for Demolition Operatives. Working at heights is normally a main health and safety problem at high rise demolition sites. The explosive demolition method prevents men from having to work at heights. It has been noticed that this method is becoming the preferred method for high rise demolition projects in the UK. Most mechanical work is carried out at ground level to minimise any incidents or accidents from occurring. 11.0 Project successes and future improvements As part of the Sandwell and Coleman partnership contract and the Coleman EMS and Environmental Policy, Coleman is committed to continual improvement in services, design, working relationships, environmental performance and sustainability with its client, the SMBC. The partnership approach aims to achieve predictability on cost, time and quality. Coleman incorporate recycling as part of their standard operations for all partnership projects, however, the past history of working with SMBC, relationship of mutual trust, understanding and open, continuous communication provided successful mechanisms achieving extended recycling targets into the project delivery process and sustainability objectives. The actual recycling rate of more than 96% for the project surpassed both the KPI of 70% and the past partnership average of 87.1%. Despite the large quantities of asbestos at the site, the recycling rate of over 96% for the project was slightly higher than the 94% recycling rate that was achieved for similar previous partnership demolition projects. Furthermore, the limited availability of alternative facilities in the West Midlands for the recycling of general waste materials that were sent for landfill has affected the recycling rate. However, this must be considered in comparison to the feasibility and environmental impacts from vehicle emissions to transport such a small quantity of possible contaminated demolition waste to a recycling facility. The recycled resource economy for construction and demolition waste materials is growing. While market prices will continue to fluctuate, like any material commodity, improved source segregation techniques and recycling infrastructure together with growing site awareness and new Codes of Practice such as Site Waste Management Plans are all helping to increase the economic viability and incentives for the reuse and recycling of construction and demolition waste. This project demonstrates that a long term contract approach, mutual trust, an open relationship and team work reinforced with agreed sustainability objectives and technical experience can overcome the limitations to flexibility in approach often caused as a result of traditional tendering. Furthermore, the partnership approach to long term contracts helps to save costs and liability to the client, provide a safe environment for the local residents, improve on the design of programmes for the contractor, and increase on quality of resources to achieve high recycling targets. 12.0 Further Information WRAP has developed a step-by-step guide to The efficient use of materials in regeneration projects which integrates the ICE Demolition Protocol together with work undertaken by WRAP on the procurement of recycled content in construction projects and site waste management plans.

Written by: Natalie Kohler and Simon Davies

Published by Waste & Resources The Old Academy Tel: 01295 819 900 Helpline freephone Action Programme 21 Horse Fair Fax: 01295 819 911 0808 100 2040 Banbury, Oxon E-mail: [email protected] OX16 0AH www.wrap.org.uk

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