“Airport Utility Buildings” are there to make our airports look nicer, but the “Blast Fence” is kind of a mixed blessing. It is 6 tiles wide, while small and medium runways are 5 tiles and the large one is 7 tiles wide. That means it is always either too big or too small to fit nicely, its width is just asynchronous. 
A 7 tiles wide Blast Fence would fit perfectly next to any runway. Just copy/paste a red or white tile of the asset to the opposite side. To me as a non-programmer it sounds incredibly easy to do. 
And as always, stay healthy and Merry Christmas everybody! 
