Is it possible to "merge" different static meshes at runtime?

Hey! Thanks for the fast answer.
So would I need to create a HISM for each part of the house? Wouldn’t it be possible to merge the whole house in one?
My doubt is that in foliage, for example, you can join several types of trees and plants in a gigantic instance.
Is there any way to take all these different static meshes and merge them into one big static mesh?