No 56 ecember 1997
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THE INSTITUTE OF HISTORIC BUILDING CONSERVATION Context and !HBC News Editor Bob Kindred, 4 Henley Road, Ipswich IPl 3FS, Tel: 01473 259441 (Ipswich Borough Council), Tel: 01473 262934, Fax: 01473 262974 IHBC Officers Chairman: Ma1y King (English Heritage, Tel: 0171-973 3853), 24 Beech Road, Aughton, Ormskirk L39 6SJ, Mobile: 0410 534911 Vice-Cbairman: Alan Taylor (Staffordshire County Council, Tel: 01785 277282), 15 Village Gardens, Walton on the Hill, Stafford STl 7 OLL, Tel: 01785 664473 Secretary: Dr Richard Morrice (English Heritage, Tel: 0171-973 3132), PO Box 301, Brighton, E Sussex BN2 lBQ Treasurer: Robert Parkinson (West Oxfordshire District Council, Tel: 01993 770247), The Old Priory, Priory Lane, Bicester, Oxon OX6 7BG Membership Secretary: Gus Astley (Bath & North East Somerset Council, Fax: 01225 477674), Manor House, Wells Road, Hallatrow, Bristol BS39 6EJ, Tel/ Answerphone: 01761 453047 Brancbes Co-ordinator: Julia Smith (Milton Keynes BC, Tel: 01908 252501), 49 Chaucer Drive, Aylesbury HP21 7LH, Tel: 01296 435187 Consultations Co-ordinator: Graham Arnold (Sefton Borough Council, Tel: 0151-934 3574), 13 Sefton Drive, Liverpool LS 3SD Education Co-ordinator· John Selby (South Cambridgeshire District Council, Tel: 01223 443000), 77 Deacons Lane, Ely, Cambs CB7 4PS Technical Panel Co-ordinator: Marion Brinton (Basingstoke & Deane Borough Council, Tel: 01256 844844), Development Department, Civic Offices, London Road, Basingstoke, Hanes RG21 4AH Publicity Ojficer: Kathy Baird (North Shropshire District Council, Tel: Business: 01939 232771, office fax: 01939 238422; Other times Answerphone/Fax: 01691 656516), Edinburgh House, New Street, Wern, Salop SY4 4DB Registered as a Charity Number 1061593. Company Limited by Gu:1rantee. Registered in England Number 3333780. Registered Office: Old Laundry Cottage, J\fote Road, Ivy Hatch, nr Sevenoaks, Kent TN15 0NT. Branch Officers North (acting).· Ian Goodman, Tel: 01670 519391 North West: Graham Arnold, Tel: 0151-934 3574, Fax: 0151-934 3587 Yorkshire: Sarah Higgins, Tel: 01653 600666 West Midlands: David Baxter, Tel: 01432 364674 East Midlands: Michael Taylor, Tel: 0116-252 7296 South.· Martin Andrew, Tel: 01494 421578 South West. Paul Dadson, Tel: 01823 255425 East Anglia (acting): John Selby, Tel: 01223 443000 South East: Nigel Barker, Tel: 0181-541 9417 London: Rosemarie MacQueen, Tel: 0171-641 2455 Scotland: Ronnie Robertson, Tel: 01343 563287 Wales. Neil Sumner, Tel: 01656 643159 Northern Ireland: Laurence Manogue, Tel: 01232 23500 ext 279 Context 56 December 1997 Context Contents News 4 THATCHING Historic thatch (Ireland) study: an interim report. J B Letts 6 Supporting Columns: Supporting a thatched roof. Brian Morton 9 Difference between long straw thatch and reed thatch hardly noticeable? Michael Munt 10 Defending the thatching tradition in East Hertfordshire. Mike Harris 12 EDUCATIONAND TRAINING Education and training for a new Institute. John Selby 14 Defining competence for an emerging preofession. Philip Grover 15 Sponsorship for conservation training. Philip Grover 16 Training and education in Scottish building conse1vation and the S/NVQ Level 5 initiative. lngval Maxwell 18 Setting standards for building conservation. John Preston 25 Student placements 27 IHBC Education Committee Student Placement Questionnaire 28 Fort Brockhurst Training Centre. Chris Wood 28 Comment There were times in the run-up to the establishment of IHBC when the sheer amount of hard work, complexity and pressure seemed about to ove1whelm the band of highly dedicated and entirely volunta1y members of (firstly) ACO, and then IHBC Council. We were rightly reminded by the Chairman, however, that it must be 'little steps for little feet'. We are a very new Institution and it will take us time to build upon the excellent and firm foundation laid by the old Association, but equally we may need to stretch our stride if we are to influence historic building conservation for the better. We have been launched upon a wide and supportive professional audience but upon a largely unsuspecting world. We must now go out and promote the professionalism of building conservation and emphasise its positive virtues and value to local communities. As part of the agenda for the new Institute we published in the final edition of ACO News (No.13 p.2) acEDUCATIONAND TRAINING (cont) British Waterways Heritage Training Programme. Nigel Crowe 30 Training in analysis and recording. Robert Hook 31 Equal rights at last? Jack Warshaw 33 Educating the structural engineer. Ian Hume 34 Current issues in the revival of traditional stone paving. Stuart hydmann and Hans Halstvedt 36 M'Learned Friend. Charles Mynors 41 Sir Titus· Moving listed buildings. David Morton 44 Green Flag Park Awards. Alan Taylor 45 Gazebo: Conserving and securing garden statuary. Judith Roberts 47 Institute News 50 Book reviews 52 Illustrations in this issue 58 tion lists for both the first six months and the second six months of our existence. One key element of the former was the establishment of the basis for the validation of conservation courses, while one key element of the latter was exploring the Institute's involvement with NVQs and CPD. This issue of Context is therefore dedicated, in part, to these important topics and has been assembled by the Institute's Education Committee under the dedicated Chairmanship of John Selby. Much of what is being proposed for conservation education and training has a direct bearing on and relationship with the Institute' s Areas of Competence - the outline of skills, knowledge and experience required to by members of the Institute. Raising professional standards was a primary motivation in forming the Institute and the creation of a clear relationship between education and training and core competence will give help give credibility to its activities and those of its individual members. 3
4 Context Editor: Bob Kindred 4 Henley Road, Ipswich IPl 3FS, Tel: 01473 259441 (Ipswich Borough Council), Tel: 01473 262934, Fax: 01473 262974 Deputy Editor: Vacant Production Editor: Jonathan David, Tel: 01582 763415, Fax: 01582 467480 Context is published quarterly and is distributed to all members of the Institute of Historic Building Conservation. © Institute of Historic Building Conservation 1997 ISSN: 0958-2746 Published for the Institute of Historic Building Conservation by Hall-McCartney Ltd, Heritage House, PO Box 21, BALDOCK, Herts SG7 SSH. Tel: 01462 896688 Fax: 01462 896677 Nonmember subscriptions to Context Context is available to nonmembers of the IHBC at an annual subscription rate, including postage, of: United Kingdon Elsewhere: £38.00 US$108.00 Subscription orders, together with remittances payable to Hall-McCartney Ltd, should be sent to the address shown above. The views expressed in Context are not necessarily those held by the IHBC or the publishers. Neither the publishers nor the IHBC shall be under any liability whatsoever in respect of contributed articles. The products and services advertised in this publication are not necessarily endorsed by the Institute. NEWS FORTHCOMING ISSUE-SDEADLINES ANDTHEMES Copy deadline for the Spring 1998 issue will be Wednesday 21 January. Please adhere to this deadline. Issue 57 will be devoted to Conservation Appraisals and Conservation Plans - What are they really for, Will the latter now being advocated for development control appraisals be confused with those requested by HLF?Looking further ahead the Summer issue will take the question of Economic Viability - must listed buildings pay? Other contributions, experiences, technical notes and case studies are welcome (space permitting). We would like to receive more items concerning points of interest emerging from conservation related Planning Appeals but only as complete (if short) articles. Please do not send all the paperwork to Context and expect the Editor to write it. Articles under 2,000 words are much preferred. Copy in word-processed form on 3.5 inch floppy disk would be appreciated where possible. Please be sure to state the natne of the software it is w_ritten in on the label. Don't just give the title of the file! NATIONATLABLOEF PROSECUTION FINES Over the last two years the Editor had been compiling tables to analyse the size, nature and success of criminal prosecutions of owners of listed buildings under Sections 9 and 59 of the 1990 Act. This now contains about 56 cases of fines over £500 and 13 cases under £500 and is organised by size of fine and by date. The latter table is to see if fines were higher in line with the corresponding increase in the maximum from £2,000 to £20,000 in September 1991. It is intended to publish this information in some form in Context in 1998. While some members have supplied details, many more have promised the information which was then not forthcoming. PPG 15 makes clear the publicity value of prosecutions in appropriate cases, but the outcome needs to be co-ordinated. If you have details of past cases it is important to let the Editor have these soon. SUCCESSFPURLOSECUTIOFNOR DAMAGINGA HISTORIPCUB Ipswich Borough Council recently successfully prosecuted Pubmaster pie, the East Anglian pub chain, for damaging alterations to the Old Bell Inn 1-3 Stoke Street, Ipswich (Grade II). The building dates in part from the early 16th century and some features from that period had survived intact. Important features had been damaged by the installation of pipework installed without Planning Permission or Listed Building Consent. The unauthorised work had involved the plumbing-in of beer chiller insulated pipework into the building. A hole had been cut in a late 18th or early 19th century outer doorway. A similar hole had been cut in the carved oak spandrel of an inner, rear cross-passage doorway of c.1540 (illustrated) - splintering the reverse face. A deep chase had also been cut in a vertical oak stud leading to the cellar. All these features are important to the special architectural and historic interest of the building, and the doorways give the Old Bell Inn a strong and distinctive character. PPG 15 Appendix C emphasises that poorly thought out COVERPHOTO Our cover photo shows the dressing of water reed on a cottage in County Waterford. It was taken as part of a research project on thatching in the island of Ireland funded jointly by the DoE (N. Ireland) and the DACG(Eire).JohnLettsofReadintroductions of services can be detrimental to the structure, appearance and character of a historic building and that the introduction of new services must be handled with care so as not to entail alterations to features such as doorways. The installation paid no regard to the importance of the features of the building. Although a Listed Building Enforcement Notice was served and complied with, this could not compensate for the serious damage to the original fabric. The contractor, Hussman Refrigeration, pleaded guilty to causing the damage but was given a formal caution as the firm had required the owners to obtain the necessary consents. Pubmaster pie as owner was successfully prosecuted in Ipswich Magistrates Court on 29 September, where the company pleaded guilty and was fined £3,000 plus £350 costs. ing University, an archaeo-botanist who has pioneered the analysis of ancient thatch, reports in this issue on the interim findings of the research commissioned by the governments of Northern Ireland and the Republic of Ireland. DEADLMYORTARS POL>CE,aCowo,.,o tJNTHELOOSE ~-f-111 TI ~ Spotted by Eddie Booth of English Heritage, it was actually about fireworks but it certainly made local Conservation Officers sit up! Context 55 December 1997
GRa§§for peiriodl window§ .A--,~~.~V\ ~ The London Crown Glass Company specialises in providing authentic glass for the windows of period buildings. This glass, handblown using the traditional techniques of the glass blowers, is specified by The National Trust, The Crown Estates and indeed many others involved in the conservation of Britain's heritage. Specify authentic period glass for your restoration projects. • THE LONDON CROWN GLASS COMPANY Twin Archway, Eli1,ahcth Road, Henley-on-Thames, Oxon. RG9 IRJ Telephone: 01491 413227 Fax: 01491 413228 ARCHITECTS & INTERIOR DESIGN CONSULTANTS Our philosophy is based upon conservative repair, well reasearched and sensitive alteration and the use of traditional materials, crafts and construction techniques. We have successfully applied these principles to our work upon some of the most important historic buildings in the country. We are committed to high quality repair and refurbishment work as well as to comtemporary design, particularly in the context of historical buildings and sites. We provide a full and varied service to our clients including specialist interior design skills,archival research and historical analysis,feasibility studies, strategic and budget planning, planned maintenance programming and co-ordination of specialist consultant teams. Our clients include • TheRoyalHouseholdPropertySection • The CrownEstate • The NationalTrust • TlzeChurchCommissioners. MARTIN ASHLEY ARCHITECTS The Stables, 2a Friars Stile Road, Richmond, Surrey TWI0 6NE Telephone 0181 948 7788 Facsimile 01819485520 Context 56 December 1997 As a local family company, spanning three generations, we aim to provide personal attention, close supervision and comprehensive after sales care. For maintenance and repairs, however small, we provide a prompt reliable service. We have the experience and resources to have carried out contracts of all types and sizes, from literally a few pounds to several millions of pounds; our main objective being to provide a quality job and a satisfied client. With a large, directly employed workforce, we have the resources to cover all aspects of building work including decorating, electrical work, roofing, plumbing and heating etc. together with a full design and planning service. Many of our craftsmen are trained and experienced in the more specialised areas of their crafts, such as:- Specialist paint techniques Running decorative plaster cornices and mouldings Use of traditional lime putty in brickwork and plastering Purpose made joinery We run a large joiners shop from which we faithfully reproduce period joinery such as doors and windows, stairs and mouldings as well as designing and manufacturing high quality bedroom and kitchen furniture. Our estimates and advice are free. R.W. ARMSTRONG & SONS LIMITED HIGH QUALITY BUILDING AND DESIGN ALDERMASTONROAD, SHERBORNEST.JOHN, ~-I!I BASINGSTOKE,HAMPSHIRE RG249JZ ; ~; •ELEPHONE (01256)850177 FACSIMILE(01256)851089 Aegis1eredHouse.Bwlder THE TRADITIONAL LIME Co. • matured lime putties • mortars • renders • plasters • lime washes • pigments TRADLYM® TODAY'S BOND WITH THEPAST Church Farm, Leckhampton, Cheltenham, Glos GL51 5:XX Telephone: (01242) 525444 Fax: (01242) 237727 5
6 Historicthatch(Ireland) studya: n interimreport J B Letts reports on an important project which it is hoped will produce a detailed picture of Irish thatching practice. In the early spring of 1996, a research project on the history of thatching in Ireland funded jointly by the DoE (N. Ireland) and the DACG (Ireland) began with a tour of 40 thatched buildings in Ulster province. The study is being conducted by John Letts of Reading University, an archaeobotanist who has pioneered the analysis of ancient thatch over the last four years in research projects commissioned by English Heritage and the governments of Northern Ireland and the Republic of Ireland. In an initial study of 'smokeblackened' thatch recovered from the base coats of late medieval open-hall buildings, and in Thatching in England from 1790 to 1940 undertaken jointly with building historianJames Moir, Mr. Letts has integrated the in situ evidence from excavations of ancient, multi-layered thatched roofs with ethnographic, historical and technical data to provide an overview of thatching over the past five centuries. This provides the academic and historical basis for legislative action which English Heritage which has been under pressure to adopt to protect historically significant roofs, materials and thatching techniques. Research on thatching in Ireland follows roughly the same approach and has broadly similar goals, although with a greater emphasis on recording the in situ evidence which survives from every historical period and highlighting technical issues which could improve the performance - and hence the economic viability- of thatch vis a vis common alternatives. The research is propitious as traditional Irish thatch is in an advanced stage of decline, but evidence of the techniques and materials used in the Flax thatch, County Londonderry. past survives either under corrugated iron or on semi-derelict houses scattered throughout the countryside. The new'Euro-thatch' that is emerging to take its place relies on imported materials and methods which are far removed from Irish tradition and are in many ways unsuited to Irish climatic conditions. An integrated study will provide a basis for legislation which could help preserved at least a portion of ancient Irish thatched roofs, as well as elucidate some of the underlying factors that should be taken into account by owners, thatchers, architects and Conservation Officers as 'Irish thatch' adapts to the economic and technical realities of the new millennium. ProjectBrief The core of the field work involves surveying a selection of multi-layered thatched roofs in each of the four provinces of the island oflreland. Each building is 'excavated' as thoroughly as possible in order to establish a chronological sequence in terms of the materials and techniques used at each rethatching. Essential constructional aspects of the building and roof structure are also recorded, along with details on the local environment and agriculture that will help situate the building in its historical and economic context. Wherever possible, local informants are interviewed to obtain more detailed information on the building and thatching materials and practices once used in the local area. A photographic and video record is also made of the building, the roof and the excavation. Samples are taken of every layer of thatch revealed, and these are later analysed in the laboratory in order to identify the species used and the way in which they were harvested and processed for use as thatch. An immense amount of reliable ethnographic data on thatching in Ireland survives in a unique collection of replies to a questionnaire on thatching that was circulated to thatchers in most counties by the Irish Folklore Commission in the 1940s. Approximately a third of the c.500 replies in the Department of Irish Folklore at University College Dublin are in the Irish language and have been translated into English for the purposes of this study. This collection is without doubt the richest source of information on 'traditional' thatching practices available anywhere in Europe, and will greatly Context 56 December 1997
enhance the data recovered by in situ sampling. The historical literature contains abundant information on thatching in Ireland and related topics, although more recent writings are often anecdotal and not nearly as botanically or technically 'rigorous' as one might wish. These sources provide the basis for sketching a broad history of thatching in Ireland taking into account many of the social, economic and environmental changes that have occurred in recent centuries. A great deal of information can also be obtained from photographic archives, particularly in reference to the appearance and techniques used for ridges, eaves and gables. Some modern Irish thatchers still use methods and materials that disappeared long ago in England, Scotland, Wales and the Continent. An effort is Eel grass and straw, County Down, Northern Ireland. being made to interview, and when possible record, these practices as most are unlikely to outlive the generation of thatchers now approaching retirement. The older generation's intuitive understanding of thatch and the link between structure, materials and performance is crucial to the success of thatch in the future whether a roof is thatched with rushes, oat straw or imported water reed. The technical basis of thatching has already been sketched in considerable detail by Mr. Letts in his work on thatching in England. Work completed Sampling For the purposes of this study, buildings surveyed fall into three categories: (a) derelict buildings that are sampled and recorded in detail; Turf and marram grass, County Donegal. Context 56 December 1997 (h) inhabited dwellings that are surveyed, but which provided limited sampling or recording opportunities; and (c) buildings with modern thatched roofs (i.e. replaced within the last 50 years). As much time as possible is being devoted to the recording of level (a) buildings as these will soon be lost due to general dereliction. Unfortunately, these buildings are not always easy to locate. Level (b) buildings can also provide data of technical, historical or botanical interest. Recording of the in situ evidence began in the spring of 1996 with a tour of Ulster Province, and has been followed by additional sampling visits to Leinster, E. Munster and N. Connaught. The success of the first Ulster tour was clue to the fact that buildings suitable for analysis had already been identified by the Environment Service of the DoE. Sampling in the South has been less methodical, but nevertheless successful because of the sheer number of derelict thatched buildings that exist in most southern counties. As of September, 1997, 24 level (a) buildings have been sampled and recorded in Ulster Province along with c. 25 in S. Leinster and E. Munster. A further c. 20 have been swveyecl to level (b) in each province. A dozen buildings have been surveyed in North Connaught and a half dozen in the Dublin region. Further sampling visits in October and November will focus on Munster and West Connaught, and the sampling component of the project will be completed by the encl of November. In general, sampling has gone more slowly than originally planned due to logistical difficulties and the need to develop local contacts. Locals are invariably aware of buildings suitable for surveying, whether derelict or inhabited, and home owners are almost always happy to provide access, but these contacts take time to develop and are difficult to pursue during short sampling visits. A number of contacts were provided by Mr. Peter Brockett, a thatcher and thatch instructor, who unfortunately passed away in the summer of 1996. Many buildings have also been located through historians and individuals with a strong interest in vernacular architecture. In contrast, and with a few notable exceptions, the response from county councils for assistance in locating suitable buildings has been less than enthusiastic. On occupied buildings, sampling is constrained by the type of rethatching that is occurring. Traditionally, a new top coat or patch was simply 'scolloped' or 'stuffed' into a weathered coat when required. Older thatchers are always eager to talk about the 'coating' methods they are using, but such roofs do not provide sequential series of samples as they offer access only to surface layers. Contemporary practice often involves stripping roofs completely for rethatching with either water reed or combed wheat reed, and numerous complete series of samples have been obtained from roofs being rethatched by a recently trained younger generation of thatchers. Semiderelict buildings provide the ideal sampling opportunity as they can usually be partially dismantled, recorded and sampled as methodically as time permits. Waterford, Wexford, Kildare and Kilkenny counties have been particularly rich in such 'sampling opportunities', and the additional effort devoted 7
■ --~ 8 to this region is justified by the variety of practices and materials discovered and the general applicability of this data to other regions. In contrast, derelict thatched dwellings are rare in adjacent Co. Wicklow, although the two that have been recorded revealed unusual materials and methods that will contribute significantly to the overall story. No building can be ignored, as almost eve1y building visited to date has provided evidence for idiosyncratic detail and a considerable degree of regional and local diversity in the principal materials and fixings employed. Materials research Modern Irish thatch is largely derived from oat and rye straw, whereas many of the older roofs excavated so far have a basal coat of wheat straw. This suggests that the shift to oat for thatching is a relatively recent one in many areas. Contempora1y thatchers would certainly use straw of"tougher', longerlasting varieties if these were available, but unfortunately almost no stocks of ancient Irish wheat or oat varieties survive in Ireland. One must turn to gene banks in Wales, Scotland and England for small samples of varieties similar to traditional Irish varieties that must then be multiplied over several years to reach production level. A ve1y rare example of an ancient, genetically-diverse 'land race' populations of bristle oat (Avena strigosa) was recently discovered by Mr. Letts in a remote part of Donegal and is currently being multiplied for experimental purposes. Netted thatch, County Donegal. Flax thatch, County Armagh. Some oat varieties undoubtedly produced high quality thatching straw in the past, but a short life expectancy for a thatched roof now seems to be accepted as inevitable - perhaps because of growers' attempts to produce marketable grain as well as straw from the same crop. The evidence suggests that a considerable increase in the longevity oflrish thatched roofs could be achieved by growing older varieties better suited for thatching, reducing the use of chemical fertilisers and harvesting the straw while a little unripe. Experimental plots of a few older varieties of wheat and oats were sown for experimental purposes in Oxford and Co. Kildare in late 1996 to provide a basis for discussing the potential for varietal research in Irish thatch. The preliminary results of a screening trial of c.250 old wheat varieties being undertaken by Mr. Letts at the University of Reading in Berkshire, England, will also be available soon, providing a basis for selecting suitable wheat varieties for more detailed analysis under Irish growing conditions. Collection and analysis of ethnographic and historical data The translation of the Irish language replies to questionnaires and associated sources in the Department of Folklore at UCD is nearing completion. This work is being carried out by Diarmuid 6'Gruagain under the supervision of Crfost6ir Mac Carthaigh, and will eventually be made available to interested researchers through the Folklore Department. The unanticipated richness of this resource has encouraged a greater emphasis to be placed on the ethnographic data compared with studies of thatching in England. Preliminary results The in situ record of thatching in Ireland has turned out to be far richer than had been expected, both technically and materially, and Irish roofs clearly hold treasure troves of data useful to historians of agriculture, the landscape and vernacular buildings. Equivalent diversity in England and the Continent appears to have been ~tripped away long ago, and Irish roofs are thus unique in a wider context in having preserved methods and materials once much more widely used throughout Western Europe. The evidence suggests that wheat straw was more commonly used than oat straw in many areas in the last century, along with barley and rye straw. Somewhat surprisingly, combined barley straw was still used in some areas until ve1y recently. Truly appalling examples of straw thatching are not difficult to find in Ireland. Cases exist of newly applied thatch that could not withstand a winter without major repair, and the oat straw currently used rarely lasts for more Straw and water reed, Ardmore, County Waterford. Context 56 December 1997
than five to seven years. In contrast, straw roofs in Wales and Western England - districts with 'Irish' rainfall and shallow-pitched roofs - routinely last for 20 years with minimal maintenance. Ethnographic records suggest that roofs were expected to last from 10 to 15 years at the beginning of this century, and the reduced longevity is at least partially linked to the introduction of modern hybrid varieties with straw too short for use as thatch. Unusual main coat and fixing materials survive in profusion; corrugated iron shields older base coats of heather in Wicklow and Antrim; decay-resistant eel grass (Zostera maritimus), collected in bulk on the shore after a storm tide, was used in a similar way in coastal districts in the North; the almost ubiquitous turf 'scraw' - whether exposed or underlain by a thin flee king of straw - provided a firm base for scallops throughout much of the country; marram grass cut on a sustainable basis from coastal dunes was used effectively on rope thatched dwellings in many coastal areas; and flax was widely used in parts of Ulster when the harvest could not be sold for the production of linen (and continues to be popular in some regions). Water reed has been cut from beds along the River Suir in Waterford and Kilkenny for generations, but in this area it is applied in much the same manner of straw and is not dressed into position as in Norfolk-style water reed. In contrast to England and the Continent, however, native reed was generally considered to be inferior to straw for reasons rooted in population genetics as much as technique. Rapid improvements in the quality of domestic Irish reed could probably be achieved with relatively minor effort. In general, the in situ, ethnographic and historical evidence suggests that 'traditional' Irish thatch once performed better than is commonly believed, and a relatively small number of material and technical changes could increase significantly the average longevity of such roofs while preserving the visual, technical and material continuity with ancient Irish thatching traditions. j. B. Lelis is witb tbe Department of Agricultural Botany, Tbe University of Reading Context is grateful to Richard Oram and Lawrence Manogue of the Environment and Heritage Service, DoE (Northern Ireland) for permission to reproduce these interim findings. A final detailed report is to be published in due course. SupportingColumns Supportinga thatchedroof Brian Morton discusses an interesting case where a badly decayed thatched roof structure was saved. The Old Hall, South Burlingham, Norfolk dating from the 16th century, has in its upper gallery some ve1y important wall painting depicting hunting scenes. Having rescued it when it was a building-at-risk, the owners have been using all their resources to maintain the building but the condition of the thatched roof over the gallery was such a substantial problem that assistance was needed. This came initially from Norfolk County Council (guiding the owners as to how to proceed), then Roofstructure,1995 Context 56 December 1997 with fu1ther support from Broadland District Council and English Heritage with grant aid. When I was initially asked to look at the roof, the problem was immediately apparent. Nearly all the cut branch rafters had been seriously affected by worm and beetle infestation to a degree where many of them had simply broken. (photograph 1) The wall paintings are found on the vertical walls of the galle1y up to the bottom of the rafter positions and also Attic gallery, 1997. in one area of the sloping ceiling itself. These wall paintings are of ve1y great importance. At the time of my initial involvement, conservator Mark Perry, from Peny Lithgow, had carried out some cleaning and consolidation of areas of plaster. The practice's role was going to be ve1y important in carrying out any work. In discussions with Paul White of BroacllanclDistrict Council and Stephen Heywood of Norfolk County Council, it was agreed that it would be accept9
able to provide a ceiling at the level where some collars exist. This gave me the opportunity to consider the form of structure that we could place within the remaining triangular space to pick up every rafter - initially in a temporary situation - but then retained as part of the permanent system of structural support. After some discussion and thought, I proposed the use of a plywood-faced lattice-girder beam constructed in timber running down the length of the roof supported either off the existing gable brickwork at each end of the galle1y or off two new A-frames distributing the load back onto the eaves brickwork. The idea was that load would be transferred from the existing rafters to the plywood beam by the use of plywood gussets profiled to the underside of the distressed rafters, even though rafters were simply hanging in the air. If we could make the structure safe enough for the thatchers to work then we would have achieved our initial objective. This would cause as little damage to the existing roof structure as possible. The plywood beam being constructed is shown in photograph 2. Taking advice from Peny Lithgow, the practice initiallyconsolidated further areas of painted plaster. Polyurethane foam was then laid against the walls and a protective covering of plywood sheets was strutted up to the wall to protect the paintings further. Mark Perry was also ve1yhelpful in advising us which plaster could be broken away to show the condition of the wall plates. In preparing our design, we had to take account of the requirement to replace the thatch leaving perhaps 6 in (150 mm) of the existing and providing a new structure over the top to support new thatch. (see sketch). We decided that this structure must be self supporting; thus, we designed a series of Aframes with the collars penetrating the existing thatch and undecorated plaster. In providing a new roof structure over the top at eaves level, the further problem is that it does not bear on the existing brick walls. We have, thus, devised a gusseted support at the base of the rafters to carry the load back onto the existing walls. Fortunately, the additional overhang front and back is hidden by the gable brickwork. Currently we are at a stage where 10 I '- I I I TheOld hall, SouthBurlingham. the plywood beam is in position and the thatcher is about to commence work. I initially thought that plywood spreader sheets would be needed on the existing roof thatch to spread the load, but the contractor - W S Lusher of No1wich - suggested that a system of horizontal scaffold tubes supported from the tempora1y roof structure would work rather better and this is the current proposal. In a project of this nature eve1y small piece of opening up suggests a change to the design proposals. It has only been with the help of the conser0 mm Water Reedthatch new air dryedoak rafter couplersand collars positioned to miss existing rafters andthatch layer plywoodgussets vator and contractors that we can progress the job in a sensible engineering and conservation manner. At the beginning of the work on site I made it clear to the contractors that nothingwaswritteninstone. We would need to be flexible in our approach if we were going to be able to achieve our objective of providing a new thatched roof without damaging the wall paintings. This, after all, is the objective that we are all striving to achieve. Brian A. Morton CEng MICE Dip.Cons(AA) is consultant to the Morton Partnership. Difference betweenlong strawthatchandreed thatchhardlynoticeable? Michael Munt describes a perplexing recent appeal decision. The following curious appeal decision follows refusal of an application for listed building consent to replace straw thatch with reed thatch in Suffolk. The Inspector considered the main issue was whether or not the proposed works would preserve the architectural and historic qualities of the listed building, or whether, indeed, they would harm the building. The original 18th century barn has been converted and adapted for modern use and was considered by the inspector to still be an impressive Gracie II listed building but had lost something of its original character. The simple form of the barn structure was still obvious (the main element was, after all, essentially a large rectangular timber clad building under a dominating thatched roof) but the insertion of window openings into this simple form had, the Inspector stated, significantly detracted from the simplicity of the original concept. Nevertheless, the Inspector accepted that the preservation of the historic features of the historic building was an important planning aim and was convinced that the architectural integrity of the roof structure ought to be maintained if that was a realistic possibility. The proposal for re-thatching the existing roof was based upon the use Context 56 December 1997
of reed thatch but the Inspector accepted the evidence before him that long straw thatch would historically have been more readily available in the area and that this would be the traditional material for the locality. He acknowledged that the nature of the material itself is such that the form of a finished roof in long straw thatch would be more rounded and less crisp than a roof thatched in the tougher reed thatch but that the difference between the two materials would be more apparent in the case of a complex roof with dormers or outshots which would require the different slopes to be gently merged or swept in together to preserve the character of the building and also to ensure a watertight construction. The existing form of the main roof element was extremely simple comprising two plane slopes between the end gables of the building. In consequence he concluded that the visual difference between long straw thatch and reed thatch would be hardly noticeable in itself, especially if the thatcher were to take pains, as suggested, to round off the crisp edges which are more typical of reed thatch. In these circumstances he had no doubt that the visual differences between reed thatch and the long straw thatch which has been used on other buildings in the vicinity would not be noticeable once an initial period of weathering had taken place. He concluded that the use of reed thatch would serve to preserve the essential qualities of the historic building, subject to certain conditions to control the detailing, and that in view of the overall merits of this building there was little to be gained by preserving a long straw thatch roof as a specific feature when a reed thatch roof will be practically indistinguishable. He considered that the re-thatching proposal should be allowed as an exception to the general advice on HERITAGE thatching given in PPG 15para.29. and those in the County Structure Plan and Deposit Draft Local Plan. Furthermore, he took into account the weathering qualities of reed thatch accepting that the greater resilience of the reed would se1ve to protect the building for longer, if properly maintained, and that to insist upon long straw thatch would impose a very significant cost burden in the medium to long-term. In his view these arguments brought additional support to the appeal. Apart from the thatch material itself the Inspector stated that decorative details to thatched roofs vary in different parts of the count1y and was particularly concerned that the ridge details should be appropriate to its location, bearing in mind the simple but effective style which has been used on the existing roof. His view was that it was not necessary for the new roof finish to follow slavishly the pattern of the old, nor was it possible for detailed working drawings to be approved for such work with the meticulous care that might be appropriate to other details of buildings. The thatcher's art depended too much on the flair of the individual craftsman for that to be practical. Nevertheless, he believed that it would be realistic for a design statement, accompanied by a drawing or sketches, to be submitted to and approved by the Council to ensure that the traditions of that part of Suffolk were respected and imposed a condition to that effect and allowed the appeal. Michael Munt, the Mid Suffolk Conservation Officer, has made tbefollowing observations. Unfortunately, the Mid Suffolk Local Plan policy on this matter does not specifically cover thatch as a material to be retained in its present form. Rather, we have added to our policy a note which states that we will adopt the criteria in PPG 15, Annex C, paragraph C.29 of which specifically states that "When roofs are re-thatched, this should normally be done in a form of thatch traditional to the region, and local ways of detailing eaves, ridges and verges should be followed". Whilst the Inspector did discuss the eaves detail he did not pick up the wraparound verge which is prevalent in Mid Suffolk and which can only be satisfactorily done in long straw. There are two aspects of this decision which give cause for concern to Conservation Officers everywhere. The first is the philosophy adopted by an inspector who states that "there is little to be gained by preserving a long straw thatch roof as a specific feature when a reed thatch roof will be practically indistinguishable". The message to be read from this is why bother about such matters as the thickness of glazing bars, or the profile of the mortar joints as most people are not going to notice anyway?. Moreover, a later statement that in the inspector's view there is no need for the new roof pattern "to follow slavishly the pattern of the old", makes one wonder whether we should be bothering to encourage craft skills at all. Has SPAB got it all wrong? Secondly, the Inspector's assumption that to insist upon long straw would impose a "very significant cost burden in the medium to long term" is open to dispute and could be used to justify the use of second rate materials in other sensitive situations. As if to rub salt into the wound, a condition was attached to the appeal decision (which was left to the district council to enforce) asking for a design statement to be submitted which would presumably "round off the crisp edges" of the reed thatch. Surely if reed thatch is acceptable as a material it should not have to pretend that it is long straw? (Mid Suffolk Dislricl Council Planning Inspec1ora1eRefT/APP/W3520/F/96/813073/P8June 1997) MANAGEMENT SYSTEM ❖ ListedBuildinys ❖ Propert1,1fflanayement ❖ Linkedtodiyitalimayes • Available NOW • Receivedwith ACCLAMATION! • Unbeatable Imaging • Network ready • GIS linking, seamlessly • Greenbacksscanned, digitisedand OCR t~r v,ienA~WJ • Capture of images from digital cameras, film, slides, plans, etc. ORION IMAGING Ltd Comprehensive leaflet and demo disk available from: Tel:01633868811 Fax:01633868968 E-Mail:inlo@orions.co.uk Internet: htp://www.orions.co.uk Context 56 December 1997 11
Defendingthethatching traditionin EastHertfordshire Mike Harris discusses problems in maintaining the traditional simple local style of long straw thatching. With the approaching millennium, all appears relatively harmonious within the ancient craft industry of thatching in East Hertfordshire although this situation has not been achieved easily nor without vigorous debate. The threat to the very existence of thatched roofs has largely receded through the protection afforded by listed building legislation, local plan policies and, in this area, the use of the Historic Building Grants system. Social changes have also benefited the craft as the possession of thatched property has now somewhat middleclass cachet, where historically, thatch was the cheapest of vernacular roofing materials for agricultural workers housing. Long gone are the days of the wretched image of thatching as recorded in 77.1eBuilder (28 June 1845) "Thatching waste. It would be impossible, after having entered so generally into all the various details connected with homesteads, to omit one most important consideration respecting them. I allude to the habit; too often in use, of thatching buildings. 'Ibis cannot be too generally reprehended. Tbe arguments against it are endless~-it entails considerable expense, robs the land, creates danger from fire, is a harbour for vermin. Either of these objections is a sufficient reason for stopping this monstrous practice." Due in part to the generally poor rural economic climate in the 18th and 19th centuries and up to the Second World War, England has been left with a generous legacy of thatched buildings. Fortunately for posterity, the cost of tiling or slating these buildings could not be afforded. In East Hertfordshire, approximately 250 of the District's 4,000 listed buildings are thatched, and most of these are in the local tradition of long straw. Since the 1960s, however, there has been a greater threat to the distinctive 12 • Enthusiasticblock cut ridge. character of long straw thatch within this part of the count1y than in all the previous centuries of use. These threats are threefold: (a) the nitrate problem; (b) the increased popularity of wheat reed and water reed; and (c) the elaboration of ridge designs and associated detailin.g The overuse of nitrates in agriculture has been well documented, where the increase in grain production was at the expense of the quality of straw for thatching. This has been largely dealt with by thatching straw being specifically grown for the sole use of the industry. Nevertheless, the knock-on effect of poor long straw production Historic evidence, c. 1890. was the wider use of combed wheat reed and water reed thatching, thereby significantly changing the character of the local historic roofscape. East Hertfordshire District Council's Historic Building Grant system has enabled the Conservation Officers tomonitor this situation closely. By targeting grant aid at rethatching projects, there has been a success in restricting the insidious spread of wheat reed and water reed, and long straw has been reintroduced to properties that had been rethatched in wheat reed in the post-war period. By combining enhancing grant aid with the requirement for listed building consent for a change from longstraw the situation has largely been brought under control. One unfortunate side effect of the Council's firm line has been the emergence of a hybrid thatch - combed wheat reed dressed up as long straw. This has proven a more difficult issue to deal with and the control of this practice hinges crucially on an accurate definition of long straw. Much debate has taken place between Conse1vation Officers, English Heritage, SPAB, the Master Thatchers Association and thatchers themselves. The result is now the wide acceptance of the definitions of long straw from two sources. The first definition from the East Anglia Master Thatchers Association is: "Longstraw should bea hollow stemmed winter grown wheat with minimum averagelength of30inches(750mm). Currently, the main varieties in use are MARIS WIDGEON,MARIS HUNTSMAN, AQUILLA, SQUARE HEADED MASTER and MASTERPIECE. Tbreshing should leave the straw stem as little bruised and broken as possible. Long straw is composed of loose uncombed material dampened and shaken into a bed. The straw is then pulled out in bunches with ears and butts dispersed randomly Context 56 December 1997
Before and after rethatching, Sawbridgworth. to both ends toform yealm.s: these are applied to the roof with tbe revealed ends undressed." The ends are finished by raking and some clipping and the long straw is rodded at the eaves and gables. The second definition, gleaned from many years of practical experience, is from a detailed research paper produced by Peter Brockett, a good friend to many in the regional thatching industry who sadly died last year: "A simple definition of tbe tradition of long straw is a thatch material that can he easily bedded and fixed on to a roof andfinished on the sU1face to an even plane without the need to dress (i.e. lightly beat) into position." With much discussion with East Herts Grants Officer and Conservation Officers, most thatchers now working in the District are using this accepted traditional approach with a certain sense of professional interest and pride. The third problem to arise over the past twenty or thirty years has been the introduction of highly decorated block cut ridges to long-straw roofs. This has been a damaging trend, obscuring thatching's distinctive regional characteristics. Photographic evidence of long-straw thatched roofs taken between the wars show nearly ·au having flush ridges. Such evidence points to Context 56 December 1997 the fact that block cut ridges are a recent introduction on long-straw roofs. Unfortunately, this situation was made worse as simple block cut ridges soon transformed into elaborate, extravagant, overly decorated ridges, detracting from the simple nature of the material and the overall spirit of the building. It was also becoming obvious that the block ridge was technically inferior to the flush ridge, partly due to the extra amount of surface timber dressing and tying required, and partly to the drip line and subsequent deterioration created at the edge of the different thatching planes. This form of ridge seemed not to evolve from a traditional pattern or a natural evolution of good design, but rather from a deliberate commercial approach by some thatchers to win contracts, by offering showy displays of patterns produced in a spurious reference to cottage ornee designs. This disturbing trend has not been followed by a number of discerning thatchers, despite the pressure to follow this fashion among a number of property owners anxious to 'improve' the look of their rustic dwellings. Reversionary thatchers have had the support of the District's Conservation Officers, who have now impleTraditional practice, Furneux Pelham. mented a strategy to reverse this trend by making owners more aware and better informed of the technical, aesthetic and practical justification for the promotion of local long-straw flush ridges. This education process is underpinned in practice by the offer of enhanced grant aid for the retention or reintroduction of flush ridges. At first it was slow progress, particularly as thatchers, not unreasonably, would point out that if owners wanted elaborate ridgework, and were willing to pay extra, then the thatcher had little option but to comply with the clients' requests. Making owners more aware of the options and the subtle visual delight and balance that a flush ridge creates, reduces the pressure on thatchers to perpetuate inappropriate detailing. This is a long-term incremental process. No more than a dozen thatching grant applications at most come up in any one year, but every success provides an advertisement for the flush ridge further enlightening those property owners contemplating rethatching their roofs. Although Conservation Officers and thatchers are pleased with the current quality of thatching, there cannot be complacency. District Council grant aid continues to perform a crucial role as, in several rethatching projects, it was the offer of a relatively small amount of extra funds (£250 usually) that finally swayed the argument in the favour of flush long-straw. Other questions have yet to be debated and settled, such as round bale harvesting, stripped heads etc., as well as stylistic issues. Nevertheless, the spin off has been that the area now has the benefit of a group of skilled thatchers who will continue their craft well into the next century in the best traditions of the industry. Mike Harris, Conservation Officer and Laurie Humphries, Historic Buildings Repairs Advisor, East Hertfordshire District Council. 13
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