Z-Fighting artifacts on decals

[anonymous_user_03f0871a]

Hi folks,
Looks like I’m seeing some odd z-fighting artifacts using decals. In the attached image you can see z-fighting on the walls, but oddly not on the floor. Not sure whats going on here so posting in case anyone here has some ideas.

UE4.15 PC_D3DSM5 renderer.

Thanks!