"Use More Solid Walls"

[JB|JustinBieber]

Everytime I make a map I tremble at the sight of the "Use More Solid Walls" error. So I always end up making walls that mess up my map :(
My question is, does it calculate the solid walls based on the size of the map or does it require only a certain amount of open space within "x" amount of squares.

[JMM]

There's a limit to how big open areas can be, which IIRC was a little larger than the open areas in douze.

[MykeGregory]

maybe...right, use more real walls. just a thought.

[V-Man]

Remember, a solid wall is different from a non-solid cube raised high enough to look like a wall.

[JB|JustinBieber]

I know a solid wall is different from a highly raised wall....Thanks tho :)
I am just trying to figure out how to fix my map.
I kind of wanted a semi (but not too) big area in the middle but I guess ill have to work around that