Work crews are scrambling to repair snow damage to the nearly century-old Minnesota State Fair cattle barn roof in time for this year’s Great Get-together.

About 20 percent of the 117,000-square-foot building’s roof collapsed March 12 after a weekend of heavy snow hit the Twin Cities. Repair costs, which are still accruing, have already topped $1 million, according to State Fair General Manager Jerry Hammer.

Built in 1920, the brick building is primarily used during the State Fair for exhibits where people can see cattle up close. It has space for about 1,000 head of cattle.

Off-season, it is used for storage and smaller events. The annual Twin Cities Classic Car and Truck Auction had planned to use the cattle barn later this month. Instead, the auction will move to other buildings on the Fairgrounds as the repairs continue.

The State Fair this year will begin on Aug. 22 and run through Labor Day.

Work on the damaged barn began shortly after the roof collapse. Areas in and around St. Paul had gotten up to 8 inches of snow in the days before the structure gave way, according to the National Weather Service. The heaviest damage was to the southeast section of the building.

The repairs have proved challenging because the 99-year-old building is not compatible with a lot of modern building materials. Matching the structural steel and bricks, for example, has posed problems, according to Hammer.

The cattle barn has a prominent spot on the Fairgrounds — visible from the busy Como Avenue entrances — and in the presentation of the state’s dairy industry. It also houses the Fair’s milking parlor and the Moo Booth — an informational exhibit about dairy farming.