Remedial work at Lindisfarne Castle has intensified in recent weeks following the major project carried out over the winter.
Masons have been working at the south wall of the western building where they have hacked out, filled, pinned, pointed and rendered the wall.
House steward Nick Lewis, writing in the Island newsletter, said: “This is the same treatment given to the adjacent south-west-facing wall (part of the Upper Gallery bay window) and means we now have a much larger surface area which, on the outside at least, has been fully restored.
“We have also done work to the unusually high (5ft) parapet above this wall.
“All of this is to ensure the structure is breathable so we can run plaster trials on the inside face and this should all happen later in June and be evaluated later in the year.”
He also revealed that the repair of existing windows in the castle will now include the reintroduction of opening windows in some areas.
This will allow ventilation to be brought to some areas of the castle which get little or none at the moment and is also a more controllable way of getting air into the building than having big doors standing open all day.
“Our glazing specialist is going to be fitting one of these openers to the kitchen window range soon so we can test it out, along with all the other trial works,” said Mr Lewis.