How many submeshes are too many

I’ve tried to find a proper thread but have not succeeded.

I’m doing a house model and there are a lot of different textures and materials.
Because maps for objects such walls are based on tiling I cannot use one texture for all.
And every material comes from Blender as a submesh. There are not so many faces actually for each.

So If I have for a house 10-15 submeshes and 15-20 houses for a scene would it be affordable for PC and Android?

If the materials used are the same across the different houses, they can be batched together. Have a look at static or dynamic batching documentation.

Materials are the same across different houses. Just different meshes and UVs.

I’ve looked batching documentation and seems it is working. I have bathed calls.
But I cannot use static for houses because right now there are issues with different lightening for static and dynamic objects in Unity 5 right now.
And I’m not sure if I can use house as static when light is fixed because I want those to be destructible because if a wall is destructed I need to remove the whole mesh from scene and replace it with sliced mesh with rigidbodies if that is a correct approach.