Ooops, I airheaded....
I thought Battletech was N guage (1:160) which is very common at model rr stores.
That means that the building would be even bigger in scale than the minis if they are in the 1:250 range.
But even the battletech stuff changes as it matured - originally, a mech was around 30 feet tall, later you read where they are 30 meters tall, quite a bit of difference between a 3 story tall machine and a 10 story tall machine.