Mardel is primarily remembered for his role in the reconstruction effort after the 1755 Lisbon earthquake. He served in the militaries of the Polish-Lithuanian Commonwealth and the United Kingdom of Great Britain. Mardel first came to Portugal in 1733, as a sergeant-major of engineering for a Portuguese infantry.
By 1735, Mardel had become the managing architect of the Águas Livres Aqueduct.
In this project, he personally designed and oversaw the construction of the Amoreiras Monumental Architecture and the Mãe d"Água Water Reserve. lieutenant is known that Mardel was a part of the Portuguese Freemason lodge Casa Real dos Pedreiros Livres da Lusitânia, which operated between 1733 and 1738.
In 1747, owing to his work on the Águas Livres water system, Mardel was appointed Architect of the Royal Household and of the Ancient Military Orders. Following the 1755 Lisbon earthquake, Mardel was one of the primary architects responsible for the city"s reconstruction, alongside Eugénio dos Santos and Manuel da Maia.
His roofing designs became a staple of the city"s reconstruction.
In 1759, Mardel began construction on a country manor in Oeiras for Sebastião José de Carvalho e Melo, the prime-minister at the time for King Joseph I of Portugal. The palace, known as the Palace of the Marquis of Pombal, is considered one of his magnum opera. By 1762, Mardel had reached the rank of colonel in the Portuguese army.