Igloo is generated with exposed ladder shaft, exposed basements and partially floating igloo.

Seed: -588129531

Coords: 13, 112, -399

Steps to reproduce:

1. Create a world in creative using the provided seed.
2. Once the world has loaded up, teleport yourself to the coordinates provided above.
3. Observe igloo that is partially floating and that has exposed ladder shaft

Observed result: 

Igloo generated in a way where it is evident that there is a basement (or even that there is a structure) as the ladder shaft was is exposed to air.

Expected result:

Igloos do not generate floating, with exposed ladder shafts or basements. This way, the igloo blends into the surroundings more and it is nog blatantly obvious that there is a structure in the world, or that the igloo has a basement. The basements are meant to be hidden, not exposed.