Running a slate to raise the roof

Small-scale quarrying is to be encouraged in some of England's loveliest landscapes to provide stone slates for traditional roofs.

A shortage of the heavy gritstone slate used in the south Pennines has prompted a "Roofs of England" campaign, to be launched at the National Stone Centre at Wirksworth in Derbyshire next Wednesday.

Based on a year of research by English Heritage, Derbyshire County Council and the Peak District National Park, the aim is to revive slate production from hand-worked quarries.

The park faces a dilemma over the slate shortage. It is generally opposed to quarrying - large-scale limestone extraction has left massive scars - yet it insists on traditional materials when old roofs are repaired.

Barns and isolated buildings in the Peak District and elsewhere in the Pennines have been robbed of their roofs to feed a lucrative trade. There has been no quarrying of gritstone for slates in the Peak District for years and much of the demand has been met by salvaging old slates, often from demolished mills. But as mills have become part of the protected heritage the shortage has increased, exacerbated by the dubious use of slates on new buildings.

Gritstone slabs fetch between pounds 200 and pounds 300 a ton. The Duchess of Devonshire, who will be at next week's launch, is among Derbyshire landowners who have had buildings stripped by slate thieves.

Up to three-quarters of an inch thick, gritstone slates are laid with the biggest above the eaves and diminishing in size to the ridge. An eaves slate can be five feet square and take two men to lift. Seven generic types of gritstone have been identified in roofs in the south Pennines.

The project team has managed to acquire new slate from a two-man quarry west of Sheffield. Though not in the past used for roof slates, the quarry yielded stone capable of being cut for eaves. The campaign will encourage other small quarries to open for slate production, including those in the Cotswolds.