Interestingly, all those new Art Deco buildings survived the earthquake.
The city underwent another building boom - including a proliferation of new constructions in the various Art Deco styles - as it was rebuilt in the decade after the quake.
That period of intense reconstruction means the city became home to the world's most dense concentration of buildings in the styles of the 1930s: Art Deco, Spanish Mission and Stripped Classical.
The book The Art Deco City, published by the trust, has this to say about what defines the Art Deco style: "Broadly speaking, the style expresses the confident, brash and sometimes vulgar spirit of its age, when the excitement of speed and burgeoning technology, the social freedom of 'the new woman', the relaxation of old standards promoted in particular by the movies, democratisation and personal freedom set the modern age well and truly on its path through the 20th century."
The Art Deco City says the Spanish Mission style originated in the south-west states of North America and was popular in New World countries, especially those with climates similar to California.
"It arrived in New Zealand in 1913 when the Auckland Grammar School was completed, and in Hawke's Bay with Iona College in 1914 and the Hastings Municipal Theatre in 1915, though the former may perhaps be considered more Italian in flavour than Spanish."
The Stripped Classical style has been described as "a variation of classicism devoid of all ornamentation".
"The style was popular with finance-related businesses that wanted to give an image that they were conservative, long established, nurturing of other people's money - your money is safe with us," says Mr McGregor.
For those wanting to make sense of Napier's architecture and its various styles and history, he recommends the guided walks run by the trust, or its guide book.
"You have to bring the buildings to life with stories, as you do with any architecture."
A bid to have Napier's unique concentration of Art Deco buildings recognised through Unesco World Heritage Site status was turned down in 2011 but Mr McGregor says another push for that recognition is likely at some stage and, if successful, it will result in a boost to tourism.
Some have argued that other cities with world heritage site status have suffered from being overrun with tourists, but Mr McGregor does not share that concern.
"We will never have the problem of being overrun with tourists, except maybe on Art Deco Weekend," he says.
