A construction crew has started work on an extensive redo of a historic house at 929 Park Ave., a project that involves restoring the original structure and building an addition.

The Park City Planning Department said the house had been condemned by the chief building official a few years ago. The original parts of the house date to 1904, the Planning Department said.

Kirsten Whetstone, the City Hall planner who is handling the project, said the crews will build a two-story addition on the back of the one-story historic house. They will also build a basement.

The house was 962 square feet including an addition that was not historic. The part of the house that was not historic was removed as part of the work. The historic section of the house is 856 square feet.

The redone house will be 2,859 square feet.

City Hall holds a $207,500 guarantee that a preservation plan is followed restoring the historic house and returning it to its original location on the parcel.

The owner is from California.