Pittsburgh’s Carnegie Science Center has detailed plans for its US$21m (€18.7m, £16.1m) Science Pavilion to include 14,000sq ft (1,300sq m) of new exhibition space.

Designed by Indovina Associates Architects, the three-storey building will be built around the existing Omnimax Theater with the pavilion facing out over the Ohio River. In addition to temporary exhibition space, the extension will feature nine STEM learning labs and a top-floor space capable of hosting corporate events and social gatherings.

“With this new traveling exhibition space, we’ll be able to bring to Pittsburgh the kind of blockbuster traveling exhibitions that are all over North America now, that come to Philadelphia and Chicago and Washington D.C., but bypass Pittsburgh because there isn’t adequate space,” said the science centre’s co-director, Ann Metzger, speaking during a planning briefing. She added that the plans were six years in the making.

The pavilion’s development is part of a larger US$34.5m (€30.7m, £26.5m) campaign to expand the science centre’s STEM programme. To date, the campaign – dubbed SPARK! – has received gifts from 120 foundations, corporations, and individual donors, including 11 donations of at least US$1m (€891,000, £768,000). The largest donation came from the DSF Charitable Foundation, which gave US$5m (€4.45m, £3.85m) to finance the pavilion’s Special Exhibitions Gallery.

Construction is expected to start by the end of Q4 2016, with an opening slated for June 2018. The SPARK! campaign will also fund two new permanent exhibitions for the science centre, as well as a giant screen digital theatre and future endowment costs.