EVERETT — The Boeing Co.’s Paine Field site will buzz with activity next month when workers knock down old office buildings to make way for new carbon-fiber-composite manufacturing.

Carbon-fiber technology — crucial to the future of big jetliner production — comes to Everett at a cost. Washington coughed up huge tax breaks, and members of the Machinists union made big concessions, to make sure Boeing built the wings of the new 777X here.

According to project plans submitted to the city of Everett, the Chicago-based company will construct a 1.3-million-square-foot building for wing fabrication. The structure will house three giant autoclaves for heating the new jetliner’s 114-foot wings.

The plans also detail a second 350,000-square-foot structure just east of the main assembly building for 777X fuselage work.

The plans call that building a “FAUB facility.” FAUB means “fuselage automated upright build” — a new way to assemble airplane bodies that replaces much of the human work with automation. It also eliminates the need for a giant lathe-like structure, like that used on the 777 classic line, to rotate each fuselage section halfway through production — a very time-intensive step.

The new approach should help the company build a 777X faster than it takes to build a legacy 777 today.

Overall, Boeing doesn’t expect the number of employees in Everett — about 40,000 — to change, though the company is moving 2,500 to 3,000 office workers to another site. The company is looking for office space along the Interstate 90 corridor, in Bothell, and in east King County, according to a real estate agent familiar with the search.

Because the number of workers in Everett won’t change much, if at all, traffic to and from the site shouldn’t change, according to the permit applications.

Parking will be lost to construction, but Boeing plans to offset that by adding 300 slots to the south and by leasing another site with 1,000 spaces, according to the documents.

The 777X wings will likely be assembled inside the main factory, said Scott Lefeber, a spokesman for Boeing’s 777X line.

Boeing Commercial Airplanes CEO Ray Conner has said final assembly, too, will take place in the main building, where the company now has a “surge” line to meet 787 production goals. The company plans to phase out that line.

Dan Catchpole: 425-339-3454; dcatchpole@heraldnet.com; Twitter: @dcatchpole.