Procurement of Specialist Services

Richard Stocking

  Surveying a timber framed building in Evesham  
  Surveying a timber framed building in Evesham: a thorough specification reduces the risk of uncertainty in pricing (All photos: Richard Stocking)  

The procurement of specialist services for the conservation and repair of our architecturally and historically important buildings is complex. We need to access and select the right skills at each stage of a conservation project or repair programme. This article explores how tendering and quotation mechanisms can be used to obtain these specialist skills and services and how quality can be most effectively assured, particularly where funding bodies and owners would favour accepting the lowest quotation.


We have a rich historic environment all around us in which buildings of all shapes, sizes and types make a vitally important contribution. Our historic and architecturally important buildings provide a tangible link to our past, our cultural heritage and our sense of identity. They are precious and often irreplaceable assets.

Conserving and sustaining our built historic environment is of great importance and benefit to current and future generations. Caring for our built heritage is a dynamic, positive and proactive process which involves managing change, including reconciling the needs of today in ways that allow the value of an asset and its setting to be fully appreciated.

Conservation as a process encompasses not only the need for ongoing maintenance and repair but also for sensitive adaptation and change.

With ascribed values placed upon our built heritage and the ease and finality with which these can be camouflaged and eroded, a greater weight and emphasis is placed upon decisions made during the conservation process. While each decision may not require expert input, contribution of specialist conservation services is often necessary to guide and inform conservation decisions, to undertake repairs and implement change.

Responsibility for the care of the UK’s designated buildings and their settings falls to a wide variety of people and organisations, from private owners (who own the majority of designated sites) through to public bodies. When specialist conservation input is required, often when more intrusive and extensive work is planned, it is so vitally important that those responsible for their care (the owners and public bodies) receive the correct expert advice and input. This includes not only the services of conservation consultants and practitioners, but also those of appropriately skilled and experienced conservation contractors and conservators. Success will depend on all these people – collectively termed conservation advisers – working together as a team.

Selecting appropriate conservation advisers (such as chartered architects, engineers and surveyors, building contractors, conservators and project managers, archaeologists, heritage consultants and planners) will provide greater confidence that advice being given and received is based on a firm understanding of conservation approaches and principles. There is an expectation that those providing that advice will have an inherent awareness of potential values and special importance that a building and its setting may possess. They will be able to evaluate, justify and mitigate conservation decisions and effectively traverse the challenges of working with designated buildings. They will also have an inherent understanding of when further specialist advice, work and input is required.

It is increasingly accepted that the early engagement and integration of conservation advisers into project work is a positive step that can achieve better conservation and project outcomes for the client.

Get the wrong advisers and the results can easily compromise the values and special interest of our built heritage, while burdening their employers with a plethora of unnecessary, unforeseen and unexpected risk and challenges to overcome.

The misapprehension that ‘only the outside of a building is listed’ or ‘it’s Grade II, so only the front elevation is listed’ is still
a worryingly commonplace misconception held by non-specialists, including both professionals and contractors, as well as by those that appoint them. The consequences of misguided advice forming the foundation on which projects are planned and progressed are all too common. Given the extent that flawed counsel continues to influence projects, it must be questioned whether the true ramifications of doing so are truly understood by private owners and public bodies.


  The quality of restoration and conservation work must be carefully observed when working with historic buildings.  
  The most important criteria for assessing a tender are usually cost, quality and time frame. Where historic buildings are concerned, quality is a particularly complex issue, encompassing not only technology and traditional materials but also philisophical issues such as significance.  

In construction, tendering is usually a competitive process where bids from companies are sought by invitation to carry out specific packages of identified work, observing key values of fairness, clarity, simplicity and accountability. It is a process primarily associated with the procurement of contractors, but the process is also relevant to the appointment of professional consultants.

The principle of tendering is to ensure that true competition is achieved by applying various criteria. Generally, the three most important factors are finance, quality and time frame.

Financial criteria are commonly used to evaluate tender responses and may comprise a simple assessment of a tender sum, or a more complex financial evaluation of projected costs over the life cycle of a completed project. Assessment will sometimes be based solely on cost.

Other criteria used in conjunction with financial measures, often referred to as quality criteria, address factors such as the level of capability and previous experience of a contractor or consultant. Time frame is another important criterion.

Work and services needed within the historic built environment are incredibly diverse and are habitually complicated by commercial pressures such as budget constraints, functional requirements and inflexible deadlines. Inevitably these pressures influence the prioritisation given to criteria used to select and procure specialist advisers. Obtaining a balanced and appropriately weighted assessment matrix is however essential to make sure the most competent and appropriately skilled conservation advisers are selected. One person’s specialist is another person’s generalist.

Financial factors such as available funding and associated constraints and limitations are of course a primary concern and consideration for building owners and clients. Indeed, where grant-aid is sought for project work there is an express requirement of procurement regulations that value for money is achieved for all goods and services acquired. However, value for money is regularly misinterpreted and misunderstood, viewed simplistically as representing the cheapest offer and often confused with the term best value. This is borne out in invitations to tender for specialist contracting and professional services that procure based on financial criteria alone or where the financial element makes up the substantial part of a scoring matrix.

While commercial pressures may be present, experience shows that the cheapest cost for the provision of services on conservation projects rarely equates to being value for money.

In a tendering or appointment scenario where costs returned by those competing to provide a service are closely aligned, there is less risk associated in selecting the cheapest offer when the appropriate quality assessment and tender and appointment information has been compiled.

However, great care and scrutiny is required where a significant spread in costs are returned for the provision of a service, as commercial pressures may make it tempting to select the cheapest offer. A wide-ranging set of costs could be an indication that the information used to inform the offer (such as a brief or a set of drawings) is unsatisfactorily vague and unclear (possibly due to an inexperienced and inappropriately skilled design team), ultimately leading to uncertainty in pricing. On the other hand, where a brief or design information is clear, well defined and unambiguous, a broad range of costs may be more indicative of a lack of understanding and experience by some respondents.

Clearly, there will be occasions when a respondent may take the decision to submit an intentionally low and therefore exceptionally competitive proposal (from a cost perspective) to generate new work opportunities. If effective quality assessment is in place and confidence sought and gained that the respondent fully understands the project requirements and scope of service, then advantage can be taken.

Contract documentation and work specifications have an important role in ensuring the most appropriate contractors are appointed and that the desired outcomes are achieved. Specifications are a vitally important tool for the management of construction work and are generally prepared using either a prescriptive or performance approach, or a combination of these.

Prescriptive specifications are more detailed than performance specifications and are in effect precise method statements leaving little open to interpretation. They are well suited to conservation work because of their precise and detailed descriptions of work methods and processes and their ability to be customised and tailored to conservation work. However, their success relies extensively on the experience and proficiency of the designer. While this might be unnecessarily detailed when working with specialist and experienced conservation contractors, the benefits of providing a precise method statement are clear when the focus is on seeking the lowest cost and where there is a risk that inappropriately skilled contractors might be selected.

Performance specifications such as the National Building Specification (NBS) present criteria and principles for how work should be completed, often defining minimum standards. As the information presented about working methods and practices tends to be limited, these specifications place greater reliance on the contractor to determine what is most appropriate, based upon their experience, skills and judgement. If prepared with care and due regard to the appropriateness of content, performance specifications can be effective when work is carried out by experienced conservation specialists. Historic fabric is often full of surprises which only surface as work proceeds, and even the best specifications cannot accommodate all possible outcomes. Considerable reliance on the skills of the contractors and conservators is inevitable, not only to identify problems as they arise but also to work with the rest of the conservation team in resolving the issues. However, while some projects may suit performance specifications, interpretation by unskilled and unqualified contractors can quickly lead to inappropriate and harmful working practices being adopted on conservation projects.

The timely selection and appointment of appropriately skilled conservation advisers is vital, not only for the preparation of suitable specifications, but also for identifying the most appropriate form of specification and procurement mechanism.


  A lime render being applied to a masonry wall  
  A lime render being applied to a masonry wall: getting the right specialists' input at each stage of the conservation process is essential  

There are various tendering and quotation mechanisms that can be used to procure the services of conservation advisers. Some of the more common procurement routes are introduced here, but variations of these and other mechanisms may warrant further consideration depending on the type of project, project and site constraints, funding and programme considerations and availability of skilled input.

The most frequently used procurement routes for securing the services of a contractor are design and build (D&B) and traditional. D&B is where a main contractor is appointed to design and build a project, providing the client a single point of responsibility. Traditional contracts are where a project is fully designed by a client appointed consultant team and a contractor is then appointed to implement the designs.

Design and build The suitability of D&B for built heritage projects is questionable and potentially troublesome, and is usually considered inappropriate. However, this procurement mechanism is sometimes used where works to heritage assets form just a small part of much larger projects such as urban regeneration schemes. Problems are likely to arise because the D&B tender process usually starts before a design or set of proposals has been completed, so tender information is less detailed and the potential for ambiguity is greater than when traditional procurement mechanisms are used. Furthermore, quality can be compromised by contractor-driven commercial pressures and by the appointment of inappropriately skilled and experienced contracting teams.

Traditional When dealing with heritage assets (where understanding is key and the unexpected common), traditional
procurement mechanisms are generally more suitable as they are more likely to ensure that a suitable and appropriate professional team is appointed. They allow for greater control over designs and they provide greater certainty and clarity over what works are required and how much it is likely to cost. This approach also allows a degree of flexibility during the post contract stage should variations need to be instructed.

Two-stage tendering There are several forms of two-stage tendering in use, but for heritage assets the first stage would usually focus on the development of the technical proposals by the designers and prospective contractors together. Only once this is completed are bidders invited to enter a second stage when financial bids are considered alongside the technical proposals. The advantages of this approach are that the expertise of the bidders can be used in defining the methodology before a price is agreed, and both sides develop a clearer idea of the scope of the works, leaving less room for misunderstandings later. It is also likely to lead to more collaborative and integrated project teams with better working relationships.

Negotiated tendering A further procurement route suited to more specialist conservation work is negotiated tendering. Certain works are so specialist that there may be a limited number of providers and so competitive tendering is not easy to
facilitate. Clients may already have developed confidence in a provider.

Negotiated tendering provides an opportunity for that provider to be appointed directly, potentially allowing earlier involvement and reducing the costs of tendering.


When working with built heritage, the experience and appropriateness of those providing services is of paramount importance. So how can we assure that only the most skilled and experienced service providers are selected and appointed to work on these buildings? The following guidance is pertinent to the identification and selection of professional consultants as much as it is to contractors.

A process of pre-qualification to identify the eligibility, proficiency and competence of those providing services, including specialists, can assist in the selection and accuracy of those invited to tender for work. Pre-qualification will typically consider relevant previous experience that a company and or individual has. It will try to assess the experience of any sub-contractors and sub-consultants that may form part of a wider offering. Establishing the lessons learnt from previous projects sometimes provides illuminating information about a provider. References can be taken up at this stage and preferably visits organised to inspect live or recently completed projects, to assist in determining competence and suitability. Site visits provide an opportunity to understand how particular challenges have been overcome, how motivated those delivering projects are, and the quality of management. Independently sourced recommendations can make an important contribution to the qualification process.

At tender stage, establishing and agreeing a balanced and appropriately weighted assessment matrix is essential to ensure that competent and skilled service providers are selected.

An assessment matrix should agree a higher quality rating than price, ideally divided 70:30 or as a minimum 60:40. It is of course accepted that cost and price is and will always be an important consideration. To make sure that cost and price always forms part of any assessment, it is suggested that a 70:30 ratio places the ideal level of emphasis upon quality while still recognising the essentiality of cost.

Consultants (such as surveyors, architects, engineers, cost managers and project managers), can be appointed by competitive tender but direct appointment based on recommendation is more common. Other appointment routes are by open and selective competitions, existing relationships and framework agreements. For professionals, in addition to training, experience and membership of professional bodies, arguably the most reliable indicator of suitability is accreditation from one of the recognised institutions or bodies.

Interviewing a service provider is an important and beneficial step and should always be part of the tendering process. It provides an opportunity to seek clarification and further validation of a provider’s suitability and an opportunity to assess personalities and ease of interaction – key qualities that are so important to a successful project.

The Building Conservation Directory 2019


RICHARD STOCKING BA (Hons) DipBldgCons MRICS IHBC is a chartered building surveyor, regional director and head of conservation and heritage at SNC-Lavalin’s Faithful+Gould business. He is a member of the IHBC and at the time of writing this article a tutor at the West Dean College building conservation master class in the conservation of historic concrete.


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