The federal government offered its first look Thursday inside the $863-million renovation job on Parliament Hill's West Block, the heritage building expected to act as the temporary home for the House of Commons for 10 years.

The rehabilitation of the West Block, which started in 2011 and is expected to be finished next year, is just the first step in a massive three-stage revitalization of the Parliamentary precinct's heritage buildings. After the West Block work is complete, work will begin first on the Centre Block and then the East Block.

West Block temporary House chamber

An artist's rendition of what the temporary House of Commons Chamber will look like. Once it is no longer needed in that role, the space will be converted to six Commons committee rooms. (Public Works and Government Services Canada)

Temporary House chamber a major change

In addition to the rehabilitation of the building, the biggest change is the construction of a glass-roofed infill structure in the covered courtyard that will welcome the House of Commons chamber.

The West Block will be the new home of the House of Commons chamber when work begins to restore the Centre Block.

House of Commons Chamber

Some 5,000 assembly parts and 30,000 bolts are being used in the roof structure for the temporary House of Commons building. (Catherine Lanthier/Radio-Canada)

Prime Minister office

A first look at what will become an office for Prime Minister Justin Trudeau. (Catherine Lanthier/CBC)

During that time, the West Block will also take over a number of legislative functions, including housing four committee rooms and offices for the Prime Minister, House officers, party leaders and party whips.

Once the Centre Block work is complete, the West Block will revert to a parliamentary building, with 52 offices for Members of Parliament and their staff, and six committee rooms, including support functions.

West Block work

About 500 workers are at the job site daily. (Catherine Lanthier/Radio-Canada)

Visitor Centre

Work is also happening on the future Visitor Welcome Centre, which will be underground. (Catherine Lanthier/CBC)

Scaffolding around West Block

Scaffolding surrounding the West Block is seven storeys high. The building has been under renovation since 2011. (Catherine Lanthier/Radio-Canada)