David Orna and Juanjo Estallo have made it their business to preserve the stone-slab roofs typical of Upper Aragón (in the Pyrenees and their foothills). Juanjo has been climbing up on roofs since he was a child in Botaya. David, from the nearby village of… Ena, has worked in traditional building with stone for 15 years. They say they learned the trade from the former piquero mason-roofers and elderly locals. They are devotees of heritage conservation and derive satisfaction from renovating buildings with traditional techniques.

The trade of piquero began to disappear in the Pyrenees with the advent of half-round clay tiles and slate tiles from Galicia, as these are cheaper. But the villages in the Natural Park of San Juan de la Peña are now listed and required to respect this architectural tradition.

Though they also do general masonry work, they excel for their expertise in stone-slab roofs. This involves the use of round timbers which they themselves harvest from the woods and set to dry. Over the substructure they lay a bed of tasca turf to help the stone settle.

Another job they do is building dry-stone walls and garden or orchard terraces. They use the local Flix stone, abundant and easy to source. They often reuse stones from derelict structures or huts nearby, and thus there is no need to purchase quarried material.

All the tools they use are traditional: they cut stones with two hammers, use brick chisels and spalling or bush hammers for texturing slabs, and also work with picoleta pick mattocks (known elsewhere as alcatones), carbide point chisels, etc.

They use stone in its rough state, except for window jambs, which they give finer finishes.

Given the harsh conditions in the mountain winters, David and Juanjo distribute their work by doing interiors (trusses, renders, etc.) in the winter, and slab roofs from spring to autumn.