Cardiff City Centre Full Case Study.b2c141ca.4825

WAS006-002: Demolition Exemplar Case Study

Recycling Demolition arisings at Cardiff City Centre

Despite time and programme constraints imposed by the competitive tender process, 98% of the demolition arisings were recycled. Project code: WAS006-002 ISBN: 1-84405-361-X Research date: April 2007 Date: July 2007

Front cover photograph: Aerial view of ongoing demolition works by Cuddy Group at Cardiff City Centre using traditional demolition methodology to progressively deconstruct and recycle the various buildings. While steps have been taken to ensure the accuracy of this case study, WRAP and Golder Associates cannot accept responsibility or be held liable to any person for any loss or damage arising out of or in connection with this information being inaccurate, incomplete or misleading. Care should be taken in using any of the data provided as they are based upon numerous project-specific conditions and are subject to change. The listing or featuring of a particular product or company does not constitute an endorsement by WRAP and WRAP cannot guarantee the performance of individual products or materials. For more detail, please refer to WRAP’s Terms & Conditions on our website: www.wrap.org.uk.

Recycling Demolition arisings at Cardiff City Centre 1

Executive summary Land Securities Plc appointed Cuddy Demolition and Dismantling Ltd to demolish numerous shops, an ice rink, library, offices, car parks and other buildings at St David’s 2, Cardiff City Centre, to make way for the construction of a new retail area with associated car park. This construction programme involved design, demolition, construction and refurbishment in the city centre. Cuddy was awarded the 8 month contract worth £2.7 million for the demolition works and construction of the sheet piling system only. To date a recycling rate of 98% has been achieved. This is includes approximately 100,000 tonnes of demolition waste (90,000 tonnes of which consisted of hardcore materials) This can be attributed to the use of the Cuddy Cardiff Quality Protocol that was submitted to the EA SE Wales office and based on the WRAP quality protocol. This document allowed for the classification of the inert demolition materials as a product rather that a waste. The demolition works were carried out adjacent to a live shopping centre, residential area and traffic therefore special measures were required. All buildings were demolished, using modern procedures including the following: manual or mechanical ‘soft strip,’ followed by structural demolition of the buildings by high-reach 50 to 80 tonne excavators with concrete pulveriser attachments. Demolition works will be completed by digging a trench to remove any obstructions and backfill the perimeter of the site in advance of the sheet piling system. The construction of the sheet piling system will form the external wall of the basements for the new-build.


Contents 1.0 Introduction ............................................................................................................................. 3 2.0 KEY FACTS................................................................................................................................ 3 3.0 Project Details.......................................................................................................................... 3 4.0 The Quality Protocol for the Production of Aggregates from Inert Waste............................... 4 5.0 Project Planning....................................................................................................................... 4

5.1 Contractor Involvement .........................................................................................................4 5.2 Achievable Recycling Targets .................................................................................................5 5.3 Site Waste Management Plans................................................................................................5

6.0 Demolition works ..................................................................................................................... 5 7.0 Reuse and Recycling Activities................................................................................................. 6

7.1 Soft stripping ........................................................................................................................6 7.2 Demolition and Recycling of Inert Materials.............................................................................6 7.3 Metals Recycling....................................................................................................................7 7.4 Materials Disposal..................................................................................................................8

8.0 Recycling Rates........................................................................................................................ 9 9.0 Quality of Recycled Materials................................................................................................. 10 10.0 Drivers and Barriers to Recycling........................................................................................... 10 11.0 Environmental and Social Considerations.............................................................................. 11

11.1 Transportation.....................................................................................................................11 11.2 Socio- Economic Considerations ...........................................................................................11 11.3 Environmental, Safety and Quality Considerations .................................................................12

12.0 Project successes and future improvements ......................................................................... 12 13.0 Further Information ............................................................................................................... 12


1.0 Introduction Land Securities Plc appointed Bovis Lend Lease Ltd (hereafter referred to as BLL), as the building contractor, and Cuddy Demolition and Dismantling Ltd (hereafter referred to as Cuddy), as the demolition contractor, to demolish numerous shops, offices and other buildings in the centre of Cardiff. This case study looks at the factors attributing to and hindering the recycling rates of materials generated from the demolition of mixed use and aged buildings at St David’s 2, Cardiff City Centre. The site was scheduled for demolition during a strict 8 month time contract to make way for the construction of a new retail area with associated car park in the city centre. 2.0 KEY FACTS

£300 million construction programme involving design, demolition, construction and refurbishment of Cardiff

City Centre;

Retail shops and units, ice rink, library, offices and car parks to be demolished in central Cardiff to make way

for a new retail development;

Demolition works were carried out adjacent to a live shopping mall, traders, businesses, residents and traffic;

The Quality Protocol for the Production of Aggregates from Inert Waste was the key to the success of the

project;

98% of demolition wastes has been reused and recycled, despite no recycling targets being set.

Approximately 100,000 tonnes of demolition waste (90,000 tonnes of which consisted of hardcore material)

had been processed at the time of writing.

3.0 Project Details Cuddy, a multi-disciplined contractor, was contracted by BLL to demolish a number of retail shops, units, offices and two multi-storey car parks (some being 6 stories high) at St David’s 2, Cardiff City Centre. This area is to make way for a new retail development in the city centre.

Client: Land Securities Plc;

Main Contractor: Bovis Lend Lease Ltd

Demolition Contractor: Cuddy Demolition and Dismantling Ltd

Recycling Contractor: Cuddy Demolition and Dismantling Ltd

The £300 million construction programme involves the design, demolition, and construction of a central part of Cardiff City Centre, covering a total area of approximately 144,000 m2. Cuddy was awarded the 8 month contract worth £2.7 million for the demolition works only. The contract was procured by a lengthy, price based traditional tendering process. The construction works are being phased over two periods. Phase 1 involved the demolition of a mix of large retail store, smaller retail units, ice rink, library, market stalls and trading area, offices and two multi-storey car parks. Phase 1 is expected to be completed in mid June 2007. Phase 2 represents the construction phase and includes the retail development for a large John Lewis store and other retail shops in Cardiff City Centre and will be undertaken by BLL. This case study summarises the demolition and recycling activities of the Phase 1 demolition works.


Figure 1: Ongoing demolition works at St David’s 2, Cardiff City Centre with high reach excavators in the background.

4.0 The Quality Protocol for the Production of Aggregates from Inert Waste Cuddy won the tender on price and being able to meet the stipulated time frame for the completion of the demolition works at the site. Furthermore, Cuddy was able to keep costs low for the tender price due to their development of a site specific quality protocol (hereafter referred to as the ‘Cuddy Cardiff Quality Protocol’) for the Cardiff City Centre demolition works. It was produced by Cuddy and was submitted to the Environment Agency (EA) SE Wales office. This site specific document is a quality management system for reprocessing and is based on the WRAP document entitled The Quality Protocol for the Production of Aggregates from Inert Waste (hereafter referred to as the ‘WRAP Quality Protocol’). Cuddy’s Cardiff Quality Protocol was submitted to the Environment Agency (EA) SE Wales office in order to classify aggregates produced from the demolition arisings at the Cardiff City Centre site as a product rather than a waste. This Cuddy Cardiff Quality Protocol played a key role in achieving high recycling rates at the site and provided Cuddy with a key differentiation from other tendering contractors. Typically aggregates from demolition sites are classified as a waste and require the application of a Waste Management Licence (WML), or exemption, in order to process, reuse and recycle such materials. However, for this project, Cuddy was able to ensure that the materials were classified as a ‘product’ rather than waste, which reduced the tender price significantly. The importance of the WRAP Quality Protocol for this project, and potentially other UK demolition projects, can not be over emphasised since it prevented the need for WML applications, documentation and associated regulations, which ultimately allowed high recycling rates to be achieved for this project. The wide scale use of the WRAP Quality Protocol would facilitate high recycling rates at other similar demolition sites across the UK. 5.0 Project Planning 5.1 Contractor Involvement Cuddy competitively tendered for the demolition works and negotiated a demolition programme with BLL prior to commencement of the works. There was little early contractor involvement in the planning of the project since the work was won under a conventional tendering exercise. Approximately twelve weeks was given to the project planning stage of the demolition works. This included hand over dates, partial occupation and service terminations, method statements, risk assessments and asbestos surveys. The type 3 asbestos survey could only be undertaken once the properties were vacated and the mains disconnected.


Recycling activities carried out on site, like most demolition sites in the UK, were constrained due to time and programme pressures imposed by the main contractor and client. Even with such constraints, Cuddy were able to achieve high recycling rates based on their experiences with processing and recycling inert demolition wastes and through the use of the Cuddy Cardiff Quality Protocol. This enabled the reuse of aggregates off-site without the need for a WML. 5.2 Achievable Recycling Targets No recycling targets were set for this project. Unfortunately, not enough time was allocated for the demolition works to enable Cuddy to maximise the reuse of materials on-site. The client had the ultimate say on the amount of time that the contractor was allowed to spend on site, which was also specified as a strict requirement during the tendering process. Time and programme constraints prevented the best on site recycling of resources and only 10,000 tonnes (out of a total of 90,000 tonnes of inert material) produced on site was reused mainly by trade contractors. However, the Cuddy Cardiff Quality Protocol was the key factor to overcoming these constraints and to achieving high total recycling rates from the project. The Cuddy Cardiff Quality Protocol facilitated the immediate reuse of aggregates off-site as a product. The Phase 1 demolition works have achieved a 98% recycling rate to date. 5.3 Site Waste Management Plans A Site Waste Management Plan (SWMP) was not developed for the demolition works; however, BLL maintain detailed weekly records of how much demolition material is produced, recycled and where it is sent by tracking vehicle movements. All Cuddy projects include the need to integrate environmental, safety and quality considerations into the procurement process. The contract for this project did not apply any targets to the recycling of materials. 6.0 Demolition works Commencement of the Phase 1 demolition was delayed by the termination of services and disconnection of mains to the properties (i.e. gas, electricity and water). Once the mains were disconnected, the asbestos surveys were undertaken and the demolition works were carried out in a traditional manner starting with the removal of asbestos and any other hazardous materials.

Figure 2: The systematic demolition of the library using a high reach excavator at the Cardiff City Centre demolition site.


The area planned for demolition consisted of a combination of building types. Most buildings were constructed of reinforced concrete structures and steel framed buildings of various ages dating back to the 1950s and 1970s. All of the brick and concrete structures, and steel framed buildings where demolished, using modern demolition procedures. It began with manual or mechanical ‘soft strip’ otherwise known as ‘strip out’ works. This involved the systematic removal of all internal fixtures, fittings, and temporary structures to leave an “empty shell”. Structural demolition of the buildings was undertaken by high-reach 50 to 80 tonne excavators with concrete pulveriser attachments. The systematic deconstruction of the buildings following mains disconnection and soft stripping, allows the safe and controlled demolition of structures and the effective management of potential environmental nuisances such as dust and noise. It provides an orderly framework for the systematic identification and separation of material for reuse and recycling. At the time of the site visit demolition of the buildings was 80% completed. Once the demolition works is completed, Cuddy will dig a trench (to a depth of 4m and width of 2m) to remove any obstructions and backfill the perimeter of the site in advance of the sheet piling system. The construction of the sheet piling system will form the external wall of the basements for the new-build. 7.0 Reuse and Recycling Activities Activities on site included disconnecting the buildings from the mains, removal of asbestos, soft stripping of materials and systematic demolition of various buildings using excavators. This was followed by removal of items for source segregation and off site reuse, recycling or disposal. The sequence of works was defined during the tender estimating stage to establish the most economical solution for the demolition works within a very specific time frame and programme. The materials were identified during a pre-demolition inspection by the Cuddy’s estimator based on their knowledge of the local reuse and recycling market. The 5 key activities were as follows:

asbestos removal and soft stripping of internal soft furnishings;

demolition of buildings and segregation of inert materials for recycling;

on site source segregation and processing of demolition wastes, largely for off-site use;

disposal by landfill of timber, glass, general wastes and asbestos materials; and

processing of 10,000 tonnes of inert material for use on site.

7.1 Soft stripping Asbestos removal was followed by soft stripping. The soft stripping involved the removal of non-structural items from the building interior. Typical materials soft stripped included, plasterboard, carpets, false ceilings, furnishings, fixtures and fittings, furniture, doors and doorframes after the mains were disconnected. Soft stripping serves two purposes; firstly, it reveals the building structure, which can then be demolished and recycled with minimal contamination from other unwanted materials such as interior fixtures and fittings; secondly, it allows for the effective source segregation of materials for recycling. Soft stripping would normally be carried out at the contractor’s discretion, driven by financial incentives and market forces. However, Cuddy made a contractual agreement to soft strip before structural demolition. This played a key role in achieving high recycling rates and maintaining quality source segregation. 7.2 Demolition and Recycling of Inert Materials After soft stripping, the structural elements were demolished and inert materials were segregated and pulverised on site. Key material streams were concrete, steel reinforcement or rebar and brick. Due to time and programme constraints, treatment such as crushing and sorting were primarily carried out off-site at Cuddy’s screening, crushing and recycling facility in Leckwith, only basic pulverising took place at the demolition site.


At the time of writing 80,000 tonnes of demolition arisings has been source segregated on site and sent to Leckwith. This facility is situated only 4 miles from the demolition site minimising haulage, traffic congestion and environmental emissions. The demolition arisings were classed as a 1C product and were screened and crushed to the required specifications for reuse. Most material was crushed to the 6F2 specification or smaller but this is dependent on the end user and the product they require for use. Originally, before the Cuddy Cardiff Quality Protocol was approved by the Environment Agency SE Wales office, all demolition material was sent to the Newport recycling facility approximately 18 miles from the demolition site. However, on this project, only 10% of the total material was sent to Newport. 10,000 tonnes of demolition material has remained on site for the construction of the piling platform.

The recycling rate of 98% achieved on this project is considered optimal. However, it is evident that had time and programme allowed for it, a greater quantity of demolition material could have been crushed and reused on site for the redevelopment works. The focus of the works was to clear the site as quickly as possible to allow the construction of the new retail area. As a result, the fast track programme for the demolition works has been the main barrier to the achievement of high on-site recycling rates. The use of the Cuddy Cardiff Quality Protocol to make use of the demolition materials as a product rather than a waste has been the main contributor to achieving a 98% recycling rate, as well as the use of nearby reuse and recycling facilities for the inert demolition arisings, ferrous and non ferrous metals. Furthermore, the ‘soft stripping’ approach contributes to the good recycling rates of materials off-site despite the time constraints for the planned demolition works. 7.3 Metals Recycling Ferrous and non ferrous metals were source segregated on site for onward recycling by scrap metal merchants. At the time of writing, 5,800 tonnes of ferrous metals and 100 tonnes of non ferrous metals have been recycled by EMR in Cardiff and Swindon respectively. Although all metals were recycled by scrap metal merchants, it is worth mentioning that limited time and programme pressures to complete the demolition works restricted the cutting of reinforced rebar and structural steel on site to the desired 5’ x 2’ x 2’ specification, as normally required by scrap metal merchants to obtain the

Figure 3: Sorting, screening and crushing of hardcore and some reinforced rebar at the Leckwith site, which is another civil engineering project for two sports stadiums run by Cuddy, only 4 miles from the demolition site.


greatest revenue on this resource. Instead, uncut metal waste was sent off site in large 30 yard roll-on-roll-off (RORO) containers and less revenue was generated for the metals. 7.4 Materials Disposal Due to health and safety constraints and the need to maintain cost effectiveness, some soft stripped materials such as glass and timber became mixed during the demolition process. In order to recycle the timber and glass on site, Cuddy would have needed to increase the amount of labour required to undertake the difficult process of manually separating such material. Increased on site labour to recycle glass and timber would be to the detriment of health and safety and put labour in proximity with the demolition equipment. Instead, glass and timber fixtures and furnishings were source segregated and sent to landfill in a mixed state. Glass waste surrounded with metal frames, plastic coverings and adhesives etc was sent directly to Bryn Pica landfill in Aberdare. Plasterboard was sent to a plasterboard producer for re-processing. Most timber, compressed paper board ceiling tiles with nails, metal, treated chemicals, metal frames and plastic coverings were also sent to the Bryn Pica landfill. A total of 1,536 tonnes of timber, glass, plastic and mixed waste, and 40 tonnes of asbestos have been disposed of by landfilling at the time of writing.

Figure 4: Source segregation of metals and inert hardcore at the Cardiff City Centre demolition site.


8.0 Recycling Rates Despite not being set, Cuddy managed to obtain a 98% recycling rates Cuddy maintains a daily schedule of driver tickets for all the inert material and waste transfer notes (WTNs) for all metals and landfilled materials. The WTNs indicate the types, quantities and destinations of waste materials. The following reuse and recycling percentages were calculated based on the total tonnages of recycled material (95,900 tonnes) from the site to date.

93.85% Hardcore

6.05% Ferrous metals

0.10% Non ferrous metals

Hardcore (90,000 tonnes)Ferrous metals (5,800 tonnes)Non ferrous metals (100 tonnes)

Although the demolition works were only 80% completed at the time of the site visit, a 98% recycling rate has been obtained and is expected to be the same when the works have been completed. Typical recycling rates from demolition projects are usually in the order of 60-70%. Significantly higher rates were achieved primarily as a result of the following:

The Cuddy Cardiff Quality Protocol and the classification of aggregates as a product rather than a waste;

Use of nearby Leckwith screening, crushing and recycling facility; and

Soft stripping of materials for salvage and reuse of items.

Figure 5: On site sorting of ferrous metal into large 30 yard RORO containers for off site recycling by ERM in Cardiff

Figure 6: Breakdown of materials recycled to achieve the 98% recycling rate


98% Recycled

2% Landfilled

9.0 Quality of Recycled Materials For this project, the immediate source segregation and pulverisation of inert demolition arisings to class 1C specification followed by off-site removal of the material to the Leckwith site for further crushing and recycling played an important role in preventing their contamination and ultimately achieving high recycling rates of inert materials. The quality of materials was ensured by the Cuddy Cardiff Quality Protocol, which stated that the material would be treated as a product if the class 1C specification is achieved through pulverisation on site. Cuddy’s Leckwith site processes material according to the specifications set in the Specification for Highway Works, November 2005, Series 600. For example, the inert demolition arisings are crushed to class 1C aggregate at the demolition site where after it is then sent to Leckwith to be crushed to the Highways Agency 6F2 aggregate specification. This 6F2 recycled aggregate is being used at the redevelopment site to build the stadium, hotel and retail park in Leckwith. Waste timber and glass from the site was contaminated by other materials (i.e. metal frames, plastic coatings and nails etc). The recycling of this heterogeneous timber and glass is limited by the lack of potential markets. 10.0 Drivers and Barriers to Recycling The underlying drivers for reuse and recycling on this Cardiff City Centre project are as follows:

The financial value of recycled material resources.

The Cuddy Cardiff Quality Protocol and the classification of aggregates as a product rather than a waste;

Use of the nearby recycling facilities for hardcore and metals; and

The technical know-how, market knowledge and the Cuddy Cardiff Quality Protocol of the demolition contractor played a key role in unlocking the recycling potential of the project. As with most projects that involve competitive tendering rather than a collaborative partnership approach, the potential barriers to the recycling initiatives were programme, time and space. Programme issues and the strict time frame to complete the demolition works within 8 months, in order not to hold up the future redevelopment works, prevented the reuse of the recovered aggregate on site. Furthermore, the lack of UK facilities for heterogeneous timber and glass wastes negated their reuse and recycling. The overall 98% recycling rate to date represents an optimum recycling achievement despite the inflexibility of the tender contract. Cuddy provided significant market knowledge, and the viability of recycling was primarily

Figure 7: The percentage of materials recycled compared to that landfilled to date from the Cardiff City Centre demolition site


driven by the Cuddy Cardiff Quality Protocol. The cost of further increasing the recycling rate would have outweighed the value of the recycled materials, undermining the economic and practical viability of the initiative. 11.0 Environmental and Social Considerations Cuddy has Quality Management Systems and Standards and is a member of the British Safety council. They are BS EN ISO 9002 and BS EN ISO 18001 accredited and working towards BS EN ISO 14001 accreditation. Cuddy carried out asbestos surveys, prepared method statements and risk assessments for all their demolition projects to identify risks to human health and the environment and develop effective mitigation measures to reduce risks to an acceptable level. A key challenge for the Cardiff City Centre project was to carry out the demolition while allowing normal activities to continue in the adjacent retail shops, businesses and residential areas. The close proximity of traffic and nearby shoppers and businesses were vulnerable ‘receptors’, and care had to be taken to ensure their health and safety, control risks and manage the demolition without harm to human health and the environment.

11.1 Transportation Traffic congestion caused by vehicles removing materials from the site was kept to a minimum by using nearby recycling facilities. However, the negative impacts of reduced parking and road closures to make way for the demolition and redevelopment of this area were unavoidable. This negative impact on traffic will remain until the new car park is constructed and road closures are removed. 11.2 Socio- Economic Considerations Adjacent shopping activities, local businesses and residents also needed to be protected from potential adverse impacts of the demolition work. Cuddy ensured the health and safety of nearby businesses and residents by undertaking risk assessments prior to carrying out the works. Dust, noise and increased traffic congestion were the main negative environmental impacts as a result of the works. Dust suppressors were used throughout the works. Furthermore noise and increased traffic is unavoidable until the redevelopment is completed. Positive social impacts of the actual project works included the removal of unsightly buildings to make way for new and better facilities for the public. Furthermore, the removal of vacant building prevented antisocial behaviour that is commonly associated with vacant, derelict properties.

Figure 8: Aerial view of the demolition works at Cardiff City Centre, illustrating the proximity to live businesses, residents, neighbouring buildings and roads.


11.3 Environmental, Safety and Quality Considerations Cuddy is committed to reaching high Quality Management Systems and Standards and is accredited to BS EN ISO 9002, which underpins their commitment to continuous improvements. In August 2000, Cuddy gained the highly prestigious Quality Assurance Award by the Asbestos Removal Contractors Association (A.R.C.A.) under their site audit accreditation scheme in recognition of their excellent site standards, safe working methods and management systems. Cuddy is committed to working towards Health, Safety and Environmental Best Practice. As such, the key aims of all Cuddy projects include the need to integrate environmental, safety and quality considerations into the procurement process. Cuddy incorporated their environmental, safety and quality considerations into the traditional competitive tendering for this project. It should be noted that the tendering process did not involve any early dialogue with the contractor or main client. Furthermore, the tender did not require detailed recycling targets to be set. Instead, the long tendering process stipulated a strict time frame for completion of the demolition works within one year from commencement. 12.0 Project successes and future improvements Cuddy is committed to continual improvement in services and environmental performance for their clients. They endeavour to incorporate recycling as part of their standard operations; however, traditional competitive tendering and strict time and programme pressures often hamper the recycling of resources and sustainability objectives of a project. Cuddy successfully overcame the barriers of inflexible competitive tendering by making use of the Cuddy Cardiff Quality Protocol based on the WRAP Quality Protocol, which allowed for the classification of the inert demolition materials as a product. This document played a key role in keeping the expenses of the project low, since WMLs were not required for the recycling facility at nearby Leckwith. The use of other nearby recycling facilities and value of recycled resources provided successful mechanisms for incorporating high recycling rates and sustainability objectives into the project delivery process. The actual recycling rate of 98% to date surpassed the average 60-70% recycling rate at UK demolition sites.

Due to site constraints, some heterogeneous wastes such as glass and timber could not be recycled and had to be transported off site for landfilling. Future projects should aim to push the classification of aggregates from demolition sites as a product rather than a waste and place more emphasis on the reuse of such materials. This project demonstrates that classing the recycled aggregates as a product rather than a waste can overcome perceived barriers associated with cost and programme. Economically viable high recycling rates can be achieved far beyond the norm. 13.0 Further Information WRAP has developed a step-by-step guide to the efficient use of materials in regeneration projects which will integrate the ICE Demolition Protocol, SWMP and WRAP recycled content approaches.

Written by: Natalie Kohler

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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Cardiff City Centre Full Case Study.b2c141ca.4825

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