It's got natural light, big meeting rooms, new exhibit space and plenty of greenery.

That's what patrons of Vancouver Public Library's central branch will be treated to when the library opens the top two floors of its landmark building on Saturday.

The rooftop garden was designed by Vancouver landscape architect Cornelia Hahn Oberlander. (Johann Nertomb/CBC)

Media were invited Wednesday for a preview of the $16.8-million expansion, including a look at the much-anticipated rooftop garden.

"What you see around you is just the beginning," said VPL's chief librarian, Christina de Castell.

"This is a garden that is in its infancy and it will grow over time. We'll see honeysuckle coming down from the rooftops and the plants growing larger as time goes on."

Part of the eighth and ninth floors were knocked down to create a second atrium. (Johann Nertomb/CBC) The garden will offer new views of Vancouver's downtown skyline. (Johann Nertomb/CBC)

7,400 square metres of new space

The Colosseum-like building was designed by architect Moshe Safdie and opened in 1995.

At the time, the eighth and ninth floors were leased to the province.

Once the 20-year lease ended in 2015, the library chose to convert the floors into more public space.

The garden has only recently been planted and features all local plants. (Johann Nertomb/CBC)

Construction began in June 2017 with an initial $15.5-million price tag. De Castell said the cost went up as problems emerged with the aging building.

The expansion adds 7,400 square metres of footage to the branch, including a reading room, 80-seat theatre and outdoor terraces.

The library says the new meeting rooms will meet the high demand for programming space. (Johann Nertomb/CBC) The new gallery on the eighth floor will feature an inaugural exhibit titled morph, showcasing artwork, photographs and rare artifacts. (Johann Nertomb/CBC)

On Wednesday, workers were seen polishing the floors and putting the finishing touches to the space.

The new floors will open to the public Saturday at 10 a.m.

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With files from Johann Nertomb