Jackie Gillies, of Jackie Gillies and Associates, said this week Lodge Arrow Kilwinning No 86, on Wiltshire St, was "totally deserving" of its registration as a category 1 historic place, the highest listing available.
Ms Gillies and architectural historian and objects conservator Eimear O'Connell played a part in the $220,564 restoration of the schist building to its former glory.
The work, which was concluded in February with a rededication ceremony, included the surprise rediscovery of a rare 112-year-old dado-level stencilled frieze, which had been hidden behind Pinex walls for about 60 years.
"The [interior] paint effect is possibly unique in New Zealand masonic lodges. It's really amazing," Ms Gillies said.
"Eimear did a great job and Blair Roger drove the project."
The trust board recognised the lodge fitted the category 1 definition of a "place of special or outstanding historical or cultural heritage significance or value," when it met in Wellington last week.
The building is the 15th category 1 building in the Queenstown Lakes district and the 1067th in New Zealand.
Trust Otago-Southland heritage adviser Heather Bauchop, of Dunedin, said in a statement the level of Arrowtown support and appreciation for the lodge was reflected in its continued use as a meeting place.
"People associated with the building may have come and gone, but the one constant is the building, which remains in remarkable original condition. It is a physical link to the history and social interaction the community has had, and continues to have, with this Arrowtown landmark.
"The interior has been painstakingly and superbly restored by Eimear O'Connell to show the architectural beauty and significance that had, over the years, been covered up."
