About half of the old Discovery Centre building in downtown Halifax has been reduced to rubble to make way for a 16-storey commercial and residential tower.

Over the weekend, crews began tearing down the 80-year-old building located at 1593 Barrington St., resulting in street closures and bus detours.

All of the road closures were supposed to end Monday night but the discovery of more rebar in the building than expected has led to delays in demolition. Municipal officials said partial closures of Granville and Sackville streets should done by Wednesday night.

Update: The Halifax Regional Municipality said Wednesday that the partial closure of Granville and Sackville streets will last until 9 p.m. Thursday.

Preserving the look

The new $50-million tower was approved by the city in 2012. The application was made by W.M. Fares Group, on behalf of a numbered company — 3258146 Nova Scotia Ltd. — which is owned by the Ghosn family.

The large limestone slabs that covered the facade of the old building have been preserved, with plans to attach them to the first three stories of the building.

1593 Barrington St. as it appeared before demolition began Saturday. (Brett Ruskin/CBC)

"We've taken off all of the original limestone, we've inventoried it, stored it, we're going to clean it and put it back on the new structure," said developer Jason Ghosn. "Then we will build a tower above that."

The new structure will feature some commercial space on the first floor, which is required by city bylaws.

"From a pedestrian walking perspective it will be very much what it's always been. The exciting part is having people living upstairs," said Paul MacKinnon, executive director of the Downtown Halifax Business Commission.

Renewal 'has to happen'

In 1939, the building opened as a Zellers. It was later purchased in 2012 for $4 million by the Ghosn family. The Discovery Centre moved in 27 years ago and has since reopened on Lower Water Street.

"I remember it was the Misty Moon at one time," said Paul Kamperman, who watched the demolition as he walked by Monday morning.

"It's urban renewal so it has to happen."

The building opened in 1939 as a Zellers. (Nova Scotia Archives)

For some, the neighbouring buildings have been in a perpetual state of construction.

"There's been construction for the entire six years that I've been here," said Heather Chamberlaine, manager of Venus Envy.

Chamberlaine said her business hasn't been affected by the scaffolding and detours but the demolition makes her nostalgic.

"It's definitely been a landmark. When people ask where are you located and we'd say we're right across the street from the Discovery Centre," she said.

More demolition to come

Crews will dig down three stories to make a parking garage with 56 spaces for residents.

The demolition is yet another development underway in the tightly packed portion of downtown.

The Green Lantern Building next door is also under construction and will be gutted with its brick facade staying where it is. That project is slated to cost between $25 million and $30 million.