Restoring a Pugliese barrel vault, two hundred years later

When you walk into a Pugliese casale that has stood for two centuries, the first thing you notice is the ceiling. It curves over you in a shallow stone arc — the volta a botte, a barrel vault — and it is, almost always, the only thing in the room that was built to outlast the people inside.

Our casale was built in the late period of the Regno di Napoli, probably around 1820. It was sixty square metres of warm carved limestone, one door, two small windows, and that vault above. By the time we found it in 2022, the whitewash on the outside had been worn back to its yellowed underlayer. The wooden door barely hung from its hinges. The vault was still there.

What a vault actually is

A Pugliese barrel vault is not decoration. It's the entire roof of the room, carried as one continuous masonry curve from one long wall to the other, with no interior support. The stones are cut from local tufo or pietra leccese — soft when freshly quarried, hardening with time in air — and laid in a precise sequence so that each block pushes against its neighbour. Take one out and the whole thing should fall. They almost never do.

What goes wrong, instead, is the surface. The vault is finished in calce — lime plaster, applied in thin layers, breathable, allowing the masonry to release moisture without trapping it. Over a century or two, the lime breaks down, the surface darkens, salts blossom out of the stone. The structure is fine. The skin is tired.

The temptation, and why we resisted it

When you start, every contractor wants to gut the room and reline it. Strip the lime, render in cement (faster, harder, "modern"), maybe drop a flat plasterboard ceiling at three metres and bury the vault above it. We were offered this twice before we found Claudio Monnini, the architect, who looked up at the vault on his first visit, paused for a long time, and said: la si lascia parlare. We leave her to speak.

The structure is fine. The skin is tired. The temptation is to replace both. The work is in replacing only the skin.

So we did the slower version. We brushed the vault down by hand, repaired the three small fractures with hydraulic lime mortar, and re-rendered it in three thin coats of natural lime, finished by trowel. The cure took ten weeks. During that time, we couldn't use the room — the air had to stay dry, the coats had to set in sequence, and a heater would have made the lime crack.

The lessons we got wrong

Two things, in case you're starting a similar project and want to skip our mistakes:

One. The original window opening was off-centre. We almost re-cut it to centre it on the room — it would have looked tidier in a photograph. We didn't, because Monnini insisted the original was the original. He was right. The off-centre window is now the best detail in the room: it frames a single olive tree that's been standing exactly there since long before the window was cut. A "tidy" centred window would have framed nothing.

Two. We tried to keep the original pavimento — the stone slab floor. After six months of trying to stabilise it (water was wicking up through the joints), we accepted that the slabs had to come up. We re-laid them only along the threshold, kept the rest as a clean polished concrete (béton ciré) in a warm grey. The room is more comfortable for it. The floor was the one thing we shouldn't have tried to save.

The room as it stands

The master bedroom at Casa Andrea is now this: the original vault overhead, re-lime-plastered, breathing. The original window cut, framing the olive that has stood since before the casale. A new concrete floor in a quiet beige. Lime-washed walls — the same lime as the vault, so it all moves and weathers together.

It is not a "restored" room in the brochure sense. It's a room where we replaced what had failed and left what hadn't. There's no architectural drama in that — only the relief of looking up and seeing the same curve a shepherd's family saw on the night before their daughter's wedding in 1842. Which, in our experience, is the dramatic part.