Wicklow-based McElheron says Pippa Middleton's bridesmaid dress is also proving a hit with bridal parties.
Speaking to the Herald from her studio the Arklow dressmaker, who worked in the fashion industry in London for 10 years, says she has experienced a massive increase in people hoping to recreate the intricate lace effect of Kate's dress.
"There are a lot of girls trying to use part of Kate's dress in their own designs now," the designer revealed.
"All parts of it: the lace, the high neck, the sleeves -- they are all being incorporated into dresses now.
"Even with dresses that have no lace on it, girls, who have already planned their days, are thinking where can they get lace onto the dress."
McElheron believes the beautiful gown sported by the new princess at her wedding to the future king of England, William, will be timeless.
"A lot of people have compared the dress to Princess Grace's dress and it's a style - a traditional style that is still contemporary -- that will not date," she told the Herald.
"It's not like Diana's dress, which after a few years looked quite dated. This style is going to continue on and will be a big influence on bridal dresses because a lot of girls can relate to it."
But it is not just the royal bride's gown that is proving to be a favourite.
"Pippa Middleton's bridesmaid dress is also a massive hit with people and we are getting a lot of inquiries," McElheron added.
"It is going to be very popular even though it's a style that will only work on a certain girl -- but it is going to be huge."