Cornwall Archaeological UnitLocal expertise with a national reputation

Working with Historic and Industrial Buildings

Many historic buildings and structures areprotected by national or local legislationand understanding what is and is not

possible is not always straightforward. CornwallArchaeological Unit (CAU) have been working withindividuals, developers, planners and legislativebodies for over 30 years, enabling developmentand helping our clients get the best experiencefrom their properties whilst safeguarding theheritage that make these structures so valuable.CAU offer three key services:

• Pre-planning Heritage Statements or HeritageImpact Assessments (HIA);

• Historic and Industrial Building Recording;

• Historic and Industrial Building Consultancy.

Other services we offer include desk basedassessment, measured and topographical survey,Conservation Management Plans, cultural heritage

chapters for Environmental Impact Assessment(EIA) and archaeological monitoring (watchingbriefs) of ground disturbance associated withhistoric buildings.

Heritage Statement or Heritage ImpactAssessment

A Heritage Impact Assessment is a pre-planningdocument that outlines the historic and/orarchaeological significance of a site within its wider setting.

It typically provides a written description of the siteincluding an outline of its historic development. Itsets out the historic significance of the site, assessesthe potential impact of any proposed developmenton existing structures and/or below-ground depositsand outlines a mitigation strategy.

These documents may be required for planning appli-cations within designated areas such as Conservation

Working with Historic and Industrial Buildings

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Areas, for Listed Building Consent, or for developmentsnear areas of known archaeological significance.These statements can also be requested by the LocalPlanning Authority to assess potential developmentimpacts on non-designated areas or sites.

The scope of the Statement or Assessment will bedependent on the scope of the application. As aminimum requirement the local Historic EnvironmentRecord (HER) should be consulted and the building/sand/or area should be assessed by a heritage expert.

Historic and Industrial Building Recording

When redeveloping or working with historic orindustrial buildings, there is often a requirement for aformal record or survey to be undertaken. Methodsused can include photographic survey, measured andtopographic survey, aerial photograph interpretation,laser scanning and desk based interpretation and analysis.

The standards for this are defined by HistoricEngland guidance but largely follow the structureoutlined below.

Level 1 survey presents a visual record of thebuilding’s exterior and of any key architecturalfeatures. Recording methods will be simplesketches and a series of photographs.

Level 2 survey is a more descriptive level ofrecording. Expanding the requirements of Level 1,both the interiors and exteriors are described,drawn, photographed and interpreted. The recordis accompanied by a report outlining the building’sdevelopment and its historic functions.

Level 3 presents an analytical account of theevolution and change a building has undergone. This Level requires all the aspects of a Level 2 surveywith the addition of measured survey. The record isaccompanied by a report outlining and presenting allavailable documentary evidence. This will includehistoric map regression, the assessment and collationof old photographs and, where available, writtenaccounts and documentation that relate to thebuilding, its previous usage and previous ownership.

Level 4 recording is a comprehensive analyticalrecord of a building. It includes all aspects of Level 3,but consults all available resources to assess anddocument the significance of the building as anexemplar of architectural significance, or its role insocio-economic development regionally or nationally.

Historic and Industrial Building Consultancy

Historic building consultancy normally follows three main stages: the pre-works consultancy, site consultancy during works and archaeologicalrecording during and after works.

Pre-works consultancy

Design Teams facilitate production of plans andspecifications in advance of the proposed works.Pre-works historic building consultancy throughoutthis design period leads to general compromise and agreement. Production of impact assessmentreports including mitigation statements can beproduced by CAU following the approved designstage, as part of statutory consent procedures.

Detailed liaison with the project’s architect andappropriate statutory officers throughout thedesign and specification process ensures that siteimpacts can be reduced as much as possible.However, not all the impacts are known at the time,and cannot therefore be commented upon in detail,nor can mitigation be discussed – for example thestructural stability of masonry walls cannot all bedetermined in advance of the works.

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Site consultancy

The site archaeologist will provide historic buildings(conservation) advice and guidance for the projectteam throughout the term of the project. This workwill also seek to ensure that any conservationphilosophy is followed at all times.

Archaeological recording

Archaeological recording during works is often aconditional component of statutory planningconsent. Production of an appropriate watchingbrief report records in detail the impact mitigationrecommendations detailed in the planning conditionsand any other aims and objectives of the project.

Case StudiesHeritage Impact AssessmentManor Cottage, St Mawes

Manor Cottage is a Grade II listed building situatedin the heart of the historic core of St Mawes.Proposals to convert one of the outbuildings at therear of the property to become a holiday let alongwith partial conversion of a second outbuilding toprovide utility space resulted in a request fromBuchanan Partnership Ltd on behalf of the ownersfor a Heritage Statement to support a planningapplication.

The assessment carried out by CAU concluded thatthe proposed development would have little impactvisually on the historic character of the area if historic

elements were retained, but that alterations to oneof the outbuildings would have an impact on the understanding of its historic fabric and therefore rec-ommended that a level 2 historic building record bemade prior to the commencement of building work.

Historic and Industrial Building RecordingTrerice House

Trerice has been a property of the National Trustsince 1953. In recent years many questions havearisen regarding the historic development of thehouse and its grounds and the Trust has embarkedon a series of studies to provide some answers.Following the results of a detailed archaeologicalassessment of the gardens and grounds carried outby CAU the Trust decided to commission a full studyof the house and an associated barn.

Most dating evidence was provided by a combinationof interpretation of the standing archaeology of the building, documentary records and historicpaintings and photographs. Dendrochronological(tree-ring dating) analysis was also undertaken onsamples taken from the three main roofs in thehouse (above the Great Hall, the Kitchen Range and the Great Chamber). The results gave a timberfelling date range between the 1560s and 1580s.They also showed that timbers from different roofswere derived from the same tree, suggesting asingle felling and building programme for all threeroofs. This work also helps to confirm dates shownon overmantels in the Great Hall (1572) and GreatChamber (1573).

The Great Hall, Trerice House Holman’s and Rule’s engine houses, Caradon Hill

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Examination of the historic fabric of the houseproduced new findings resulting in some significantchanges of interpretation. The study confirmed thatthe present house occupies the site of a medievalhouse; vestiges of the medieval layout are visible inthe plan of the existing house and the barn.

Historic and Industrial Building Consultancyand RestorationCaradon Hill Area Heritage Project

This project involved structural remedial works to15 engine houses and a range of other industrialbuildings in the Caradon Hill area of east Cornwall.

The Caradon mines are nationally important mine sites, a significant proportion of the Caradonlandscape is scheduled and all are within theCornwall and West Devon Mining Landscape WorldHeritage Site.

CAU were commissioned to prepare an assessmentof the impact of the proposed works on these

important heritage assets, and to provide historicbuilding consultancy both before and during theworks. The consultancy programme ensured thatthe conservation works followed an agreedconservation philosophy to have a minimal impactduring works, and afterwards to ensure the workswere sensitively completed.

As a result of the consultancy traditional buildingmaterials were used when consolidating thebuildings, such as traditional lime mortar mixesusing locally sourced aggregates to match theoriginal mortar composition.

Andrew YoungCAU ManagerCornwall Archaeological UnitTel: +44 1872 322534ayoung@cau.org.comwww.cau.org.uk

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Local expertise with a national reputation

Cornwall Archaeological Unit (CAU) is the new name for the former Historic EnvironmentProjects team of Cornwall Council’s Historic Environment Service.

With over 30 years’ experience providing archaeological services throughout Cornwall, theIsles of Scilly and elsewhere in England, Cornwall Archaeological Unit offers a comprehensiverange of quality and cost effective archaeological services, delivered by a highly experiencedand professional team. It is a fully accredited organisation, working to ISO 9001 standards

and is a Registered Organisation with the Institute for Archaeologists.

We are committed to delivering cost effective, sustainable and affordable solutions whichsatisfy planning conditions. We also work in seamless partnership with other heritage

organisations, such as English Heritage, to deliver discretionary projects that identify, record,protect and promote the historic environment for the benefit of local communities.

For further details please email cau@cornwall.gov.uk

Cornwall Archaeological Unit, Fal Building, County Hall, Truro. TR1 3AY

01872 322057 cau@cornwall.gov.uk www.cau.org.uk