Krueck + Sexton Architects has designed a glazed office building in the Florida everglades for the FBI, using restored wetlands to create "a beautiful moat" for security (+ slideshow).

The Federal Bureau of Investigation's new seven-storey office building is its central headquarters for South Florida and officially opened in April.

Designed by Chicago-based architects Krueck + Sexton, the 375,000-square-foot (34,800-square-metre) all-glass enclosed building is meant to counter the fortress-like presence most US Federal buildings project.

"We were determined to make a building with some inspiration," said Mark Sexton, principal of Krueck + Sexton. "We designed the building for the people who work there – not just to meet the requirements of the FBI," he told Dezeen.

The restored wetland landscape is not only scenic, it also adds a layer of security. "It's basically a beautiful moat," Sexton said. "The water is a natural feature that's also a deterrent."

Using the landscape, the architects were able to eliminate the need for many of the walls and bollards prescribed by the Federal government for additional security following the 1995 Oklahoma City bombing and 9/11.

The building comprises a pair of curved bars of office space joined by a bridge containing the conference rooms and communal areas. The H-shaped plan means that every employee sits within thirty feet of natural light and views of the wetland landscape.

A metal sunscreen shields the building's south-facing side from the harsh Florida sun, while still allowing views out.

The project was built under the General Services Administration's (GSA) Design Excellence program, an initiative that allows smaller, more design-oriented firms to qualify for government contracts.

When the GSA selected the site it was lifeless and covered in a thick layer of gravel. "It was what's called an 'improved site'," Sexton said. "That's how they sell real estate in Florida."

They scraped the gravel from the site and used it to elevate the building, and then scooped out the trenches, allowing the water, plants, and wildlife to return. Krueck + Sexton worked with local landscape architects Curtis + Rogers Design Studio to restore the grounds to their lush state.

Working with sustainability experts Atelier Ten, the architects calibrated the building's facade to reduce energy use and glare, using fritted glass and the angled sunshade. Photovoltaic panels top the parking garage, further reducing the building's carbon footprint.

The building is Kruek + Sexton's largest project to date. The small firm is best known for the Spertus Institute in Chicago, a Jewish cultural centre and museum, which boasts a folded glass facade – the first contemporary addition to the Michigan Avenue streetwall in decades.

Photography is by Nick Merrick/Hedrich Blessing.

Project credits:

Lead architects: Krueck + Sexton Architects
Mechanical Engineer: WSP
Structural Engineer/Building Envelope Consultant: Thornton Tomasetti
Electrical Engineer: WSP
Civil Engineer: Miller Legg
Landscape Architect: Curtis + Rogers Design Studio, Atkins
Lighting Designer: George Sexton Associates, Syska Hennessy Group
Environment & High Performance Design Consultant: Atelier Ten
General Contractor: Hensel Phelps, Derek Hoffine
Design Build Architect: Gensler
Interior Designer: Gensler
Mechanical Engineer: Syska Hennessy Group, Inc.
Structural Engineer: Walter P. Moore