Sleight joined the business in 2021 as Managing Director of the readymix concrete division and positively transformed it during his tenure. Last year he moved to take up the role as Managing Director of the aggregates division.
Aggregate Industries' new CEO has more than 20 years of experience in the construction industry, holding various senior leadership positions.
Earlier this year, it was announced that the UK building materials major's current CEO, Dragan Maksimovic, had been appointed Region Head West Europe, overseeing the leadership of the Holcim businesses in the UK, France, Belgium, Germany and Spain.
The outgoing Aggregate Industries CEO said: "Firstly, I'd like to congratulate Lee on his appointment. He will make an excellent CEO.
"I have worked closely with him for the last few years, and he has a proven track record of leading and transforming businesses. I am confident he will continue to drive the business forward while delivering on our ambitious plans of decarbonisation and green growth."
Sleight, who will start in his new position on 1 August 2024, said: "It is a very proud moment for me to be chosen to lead this fantastic business. Having been with the company for a number of years I know first-hand how amazing the people who work here are.
"I am now really looking forward to working with our teams around the country in order to deliver on our ambition to be the UK's leading supplier of sustainable construction materials and to keep progressing on our journey to a net zero future."
Kaziwe Kaulule will succeed Sleight as Managing Director of the company's aggregates division. Kaziwe joined AIUK in October 2023 as Director of Strategic and Commercial Growth, having previously been CEO of Holcim's South Africa and Zimbabwe businesses.
