ensure that they are conserved. It is not intended to give technical advice on repairs and maintenance

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1 Roofs Roofs are an essential part of the character of traditional buildings. They require careful maintenance and repair in order to prevent serious structural deterioration of the roof structure, and ultimately the entire building. When remedial work becomes necessary, attention to detail, particularly the use of traditional materials and techniques, is very important if the special character of the building is not to be compromised or destroyed. This leafl et aims to draw attention to traditional roof materials, forms and details so that those involved in the care of traditional buildings can recognise their value and Pitched ensure that they are conserved. It is not intended to give technical advice on repairs and maintenance Hipped and you are advised to seek professional advice for anything other than minor repairs. Development of Roof Types Early buildings in the county were roofed in thatch. Thatch was used widely and almost without exception in the more humble buildings until the introduction of threshing machines which spoil the straw for roofi ng purposes. Surviving examples are mainly found in the lower lying parts of the county. More notable buildings, and by far the majority of buildings in the 18th century, used stone slate on the roofs (alternatively referred to as stone fl ag or grey slate). It elininated the risk of fi re associated with thatch and gave a more durable protection against the weather. Only when Britain s canal and rail network was established in the late 18th century and early 19th century were true slates (often referred to as blue or green slates) brought from Wales and Cumbria. Conserving your historic building Half-hipped Lean-to Gabled extension Mansard Double roof

2 Slate was widely used throughout the 19th and early 20th centuries, gradually replacing stone slate. Green Westmorland slates became fashionable towards the end of the 19th century and stone slate enjoyed a revival in the Arts and Crafts Movement of the 1880s and 1890s. Clay plain tiles were fi rst used in the county in the mid 19th century despite being used centuries earlier in other districts. They were not widely used in domestic architecture until the early 20th century. The Modern Movement promoted the widespread use of the fl at roof bringing us to the present day when roof coverings include concrete and clay interlocking tiles, pantiles, plain tiles and a wide range of sheet materials and substitutes for traditional slabs. Thatch The thatched buildings which survive in the south and west of the county represent a small fraction of the number which originally existed. Thatched roofs are laid at a steep pitch (60 degrees approximately) in order to shed water and are easily swept round corners or over complex plans. The eaves and verges normally have a considerable overhang and gutters were originally omitted completely. The steep pitch of a roof can often indicate that a building which was originally thatched has received a later roof covering at some point in history. Stone Slate (Grey Slate) Grey slates were used widely in the county but most predominantly in the 18th and 19th centuries in the Pennine areas where they were quarried. Because they were split in random thicknesses and sizes they are laid in diminishing courses, the larger slates Pitch of thatched roof Build up of bundles to form thatched roof Thatched roof with decorative scalloped pattern at the ridge

3 at the eaves and the smaller ones at the ridge. Each stone slate is held in place by a single oak peg. Ridge stones are cut from solid stone and butt jointed. Because of the diffi culty in metreing hips and valleys, roofs are normally gabled and adopt simple forms. As a consequence dormer windows are foreign to buildings with stone slate roofs. Overhangs at eaves and gables are kept to an absolute minimum because of the sheer weight of stone slates. The verge beneath the slate on the outside face of a gable is normally pointed with mortar. In some earlier examples the gable projects above the plane of the roof covering as a parapet or a coped gable. Pitch of grey slate roofs Oak peg Slate Ridge tile Mortared verge Stop end to eaves Kneeler stone Slates laid in diminishing courses 17th century crowstep as an alternative 18th century sloping coping stones on raised gable Quoins

4 True slate Centre hung slate Ridge tiles (clay) Slate True slate is used throughout the county, often as a replacement for other roof coverings. Slate from Welsh quarries is used in thin slabs of uniform size giving a precise and regular appearance. Slate from other areas of the country is cut in random sizes and thicknesses and is laid in courses which diminish in size towards the ridge giving an iirregular and more textured appearance. Eaves and verge details are usually close cut (clipped) except when architectural style or whim dictates otherwise. The ridge is normally capped with special clay ridge tiles of varying shapes and sizes. The verge beneath the slate on the outer face of a gable was normally pointed with mortar. During the 19th century every Lead roll Fishscale slates Ridge tiles Pointed verge Close cut eaves Decorative ridge tiles Decorative barge board

5 possible variation was employed to achieve stylistic aspirations, fi shscale slates, polychromatic bands, decorated ridge tiles and pierced bargeboards were all used giving picturesque and pleasing results. Less frequently a lead covered roll was used to fi nish a ridge or a hip, particularly in the Regency period. Good quality slates last almost indefi nitely. Slate roofs most frequently fail because the iron fi xing nails corrode causing slates to slip. Isolated slates can be restrained using lead or copper clips but widespread failure will require the whole roof to be re-laid. Non-ferrous nails should be used for the best results. Plain tiles Clay tiles do not feature prominently as a traditional roofi ng material in the county. They are far more common in regions where stone slates were not freely available. Special shaped and coloured tiles allow all the variety which could be achieved with slates as Clay tiles Plain clay tiles well as easily negotiating hips and valleys. Roof Replacement If a roof has reached the point where there is no alternative but to strip off the covering and replace it, advice should be sought from a contractor with experience in traditional roofi ng techniques. It will nomally be possible to salvage the majority of the original slates or stone slates and to purchase matching materials to replace any which are broken or missing. Owners are sometimes tempted to re-roof in inappropriate modern concrete tiles which can be cheaper in the short run, but remember: the life expectancy of many modern materials is untested and is unlikely to match that of slate or stone slate. Colours may change dramatically after exposure to the weather. most modern tiles have a fl at, engineered appearance which will detract from the character and probably the value of a traditional building.

6 listed building consent or planning permission may be required to change the type of roof covering. Generally the use of modern materials on traditional buildings is not advisable and is likely to be a false economy. In occasional circumstances, it may be appropriate to use the salvaged original slates on the front or more important slope and an alternative covering on the rear (for example, using salvaged grey slates on the front slope to maintain the appearance and slate on the rear. Substitute materials are now available which are designed to replicate the colour, texture and general appearance of grey slates. They are quite suited to some new build applications but need to be used with caution or not at all on listed buildings or in conservation areas. DORMER STYLES Gabled Gabled (window part below eaves) Hipped Dutch Gable Hipped Dormer (wholly in roof space)

7 Reroofing keypoints - some DOs and DON Ts Do establish whether planning permission or listed building consent is required. Do re-use the original roof covering materials whenever practical. Endeavour to match any new or second-hand materials like for like. Do consider replacing later out-of-character materials with traditional ones. Do pay particular attention to the treatment of eaves, verges, ridges and any other architectural detailing. Do ensure that the roof space is adequately ventilated. Don t consider the use of bitumen or cement coatings which are applied to the surface of the roof. Such temporary remedial measures are visually unacceptable, they reduce proper ventilation and prevent the slates being re-used at a later date. Don t consider the use of proprietary systems which secure slates by an application of an insulating/bonding agent on the underside. Such systems aggravate problems of rot and infestation in the battens and rafters and make proper overhaul problematic.

8 Advice Identifying sources of problems and appropriate remedial action will normally require the advice of professionals and contractors experienced in conservation work on traditional buildings. For further information please contact Michael Scammell eld.gov.uk Andrew Ramshall eld.gov.uk or write to: The Corporate Manager, Planning & Development Macclesfi eld Borough Council Town Hall Macclesfi eld Cheshire SK10 1DP It is the owner s responsibility to comply with all statutory requirements and seek appropriate professional advice. The Council cannot be held responsible for the specific use of these general design guides.