Remnants of the original 13th-century plaster which was painted white can still be found on some walls.
"Once you get down to the original plaster that's been discolored by the glue, just leave it," he suggests.
Visually, the new materials are indistinguishable from the original plaster.
In 2002, the church suffered a fire that destroyed the original plaster.
Some of the original plaster is on display inside the house, along with other elements of its construction.
The first floor retains much of the original plaster and marble work.
In each room she stripped a section of wall to the original plaster, then she moved on.
They are mostly finished in their original plaster.
The original plaster remains on the other side.