The most frustrating part of the build was being restricted by the parts available. "Sometimes I would be waiting for parts and I'd get too frustrated, so I had to put it away for a week."
When he couldn't find parts, like light-grey pieces for the roof, Mr Catley said he had to make some of it up, which meant looking in stores as far afield as Belgium.
Though the house was finished, Mr Catley said he wasn't, and had already ordered some Lego plant parts for the house's landscaping.
The Duart House Society Inc. committee member Debbie van Asch was wowed by Mr Catley's replica, and she said she didn't know he had achieved such a high level of detail using only Lego.
Duart House was built for the Mclean family around 1882, and later used as a primary school.
From 1926, it was rented and then owned by the Greenwood family, who gave it to the Havelock North Borough Council in the 1970s.
-The real Duart House is open to the public on the first Sunday of every month from 11.30am to 12.30pm. Those wanting to visit outside those hours should phone 06 877 6334.