I believe that's "the Red Barn" still standing, part of the museum now.
It has been moved from its original location. I remember when they moved it as a kid.
They put it on a barge and moved it down the Duwamish river!
I once worked in that old building for a brief time before it moved to the Museum of Flight. Among other things they made there were turbine engines that they tested in a Boeing fire truck. That fire truck and a hot rod with the Boeing turbine are in the car museum in Tacoma.
Paul in Tacoma