Chief Executive Stephen Harrison said an independent listing was the next step for the maker of the popular London brick as it looked to increase its production capabilities.

"The fundamentals of our industry are attractive and with our efficient manufacturing base, strong positions across all product categories, long-standing customer relationships, and significant scope for future capacity expansion, Forterra is very well placed for the future," he said.

Forterra said it expected to have a free float of at least 25 percent of its shares following the listing, which market sources said would give the group an equity value of about 450 million pounds ($642 million).

The group has been owned by U.S. private equity firm Lone Star Funds since it was sold by HeidelbergCement in March 2015. The German company bought Hanson in 2007.

Forterra grew its core earnings to 71 million pounds in its 2015 financial year, up from 22 million two years earlier, it said, thanks to its streamlined production facilities and growth in brick prices.

(Reporting by Paul Sandle; Editing by Mark Potter)