The castellations will be set on top of several turrets in the castle complex.
Owner Dot Smith was excited at the latest stage of her big project.
"They’ll finish the turrets and give them a lot of drama, especially when you see the sun set and see them standing out there ... looking majestic."
The building was expected to be finished within the next three months, but the grounds of the 1150sq m two-storey, six-tower castle would take longer to bring to completion, she said.
The castle, which is Mrs Smith’s home, has taken about four years to construct after 30 years of planning.
Seddons Plasterers, of Mosgiel, made the castellations on the turrets.
"We put the wee crown on top."
John Seddon said he was happy to take part in the North Otago castle project.
"Dot came down and we had a chat. She convinced me we had a job to do."
The castellations are made out of glass-reinforced concrete (GRC).
"My dad said, ‘If you can draw it, we can make it’."
GRC was chosen because it could be used to create detailed work and could withstand the weather, Mr Seddon said.
It was the first time he had worked on a castle but he said he would do it again.
