As part of a larger regional project intended to bring back life, heritage and tourism to the depopulated area around the Aragón River in Northeastern Spain, Zaragoza-based Sebastián Arquitectos has restored a small stone chapel outside the hamlet of Ruesta. The hermitage of San Juan de Ruesta was originally built in the 12th century; it was known for its significant collection of Romanesque paintings before the artwork was removed in the early 1960s, when a pharaonic reservoir and dam were built nearby, hastening the area’s decline.

In 2001, in an act that Sergio Sebastián Franco, founder of the architecture practice, calls “cruel and unnecessary,” the local government demolished part of the chapel’s roof and walls and covered the remains with a metal structure. The brief to the firm (which is also working on the wider master plan) was simply to restore the building, but it proposed instead to reinstate the original volume and turn the chapel into a welcome shaded respite for pilgrims on the road to Santiago once more.

Sebastián Arquitectos topped the formerly abandoned San Juan de Ruesta hermitage with a new sandstone block roof to complement the original structure while providing visitors protection from the elements.

The church’s remains are complemented by a new stone volume, slightly set back and resting on a layer of concrete that emphasizes the boundary between past and present. Unlike the original shell, with its stones laid in random sizes and patterns, the new walls are composed of overlapping and uniform CNC-cut sandstone blocks measuring 40 by 20 by 20 centimetres, made by local stone manufacturer Olnasa. The architects could have chosen a different colour or material to demarcate the contemporary insertion more vigorously, but opted to keep things monochromatic and relatively low-key.

“Our criterion was to build in a similar language as the existing chapel but using different words,” says Sebastián Franco. The shingles, also made of sandstone but cut into much thinner 40-millimetre slabs, sit atop a wooden roof and timber panels, while steel columns and beams support the volume as a whole. The slant of the slabs, which taper at the top, was the result of two objectives. “Visually, we wanted to expand the horizontal lines of the roof along the facade and produce a continuous image across the new intervention by creating a shadow effect on the lower part of the blocks,” explains Sebastián Franco.

The uniformity of the CNC-cut sandstone blocks creates a compelling rhythm. Slanted to promote rainwater runoff, the tiles also feature small square holes that reference the original building’s putlog holes, furthering the seamless nature of the renovation.

More practically, the inclined design evacuates rainwater naturally. Small openings known as mechinales on the lower left corner of each block reference the small putlog holes still visible in the original apse while also ventilating and illuminating the interior. “We wanted to restore the light conditions of the ancient chapel, where simple candles would have been used, and reproduce that intermediate phase between darkness and light.”

The always-open arched entrance and a narrow rectangular void above let even more natural light filter in throughout the day, creating dramatic illumination effects in different dimensions. A nice final touch is how the original stones left over from the 2001 demolition have been re-used: Laid around the chapel at equal distance from one another, they create a grid pattern that echoes that of the chapel’s new (and old) walls.