MISSOULA, Mont. -

The last of the tenants who were temporarily relocated from the Palace Apartments will move back into their homes by the end of the week.

The downtown landmark's top floors are low income apartments.

But since June, the entire structure has been undergoing major historic restoration.

The interior work is almost done on the building, which is on the National Register of Historic Places.

If you've driven or walked down Broadway you've probably seen the workers perched in cranes high above street level.

They've been putting final touches on new custom made energy efficient windows in the old Palace Hotel.

Workers uncovered top portions of some windows which had been buried in a false ceiling.

"To recapture the light and the grandeur," said project manager Sam Oliver from Bristlecone Development.

Oliver said the challenge was getting a massive amount of work done in a short time frame, while the building was partially occupied.

Tiny details from roof to basement.

For instance, historic trim practices, said Oliver.

"Trim practices that are no longer available that had to be custom made," he said, "and custom cut."

The original multi- story hotel was built in 1909.

An addition was built in 1941 and attached to the original.

"I take great enjoyment taking some of Missoula's old iconic buildings and rehabbing them so that we can see them for decades to come," said Oliver.

There's a new heating and cooling system.

There are solar panels on the roof.

The exterior on the back of the building has been restored with common brick, a low fire, soft brick, historically used in low visibility areas because it was cheap.

"It's really enhanced the downtown," said Missoula Housing Authority director Lori Davidson,"by being able to restore all of the beauty of the exterior."

The Missoula Housing Authority has about 60 low income apartment units at the Palace.

"We have five studios, eight two bedroom and the remainder are all one bedrooms and there are some vacant units on each floor," said Davidson.

That's about 15 units.

Restoration will also start on parts of the ground floor, which houses the lobby and several businesses.

The Missoula Housing Authority's next step will be to renovate the street level's exterior of the old Palace Hotel.

It will be restored to look the way it did in 1941.