Modular Building With Nanite Optimization

I have moderate experience with UE 5 but I need help I don’t know what to do. I created a building with modular pieces that I downloaded from bridge with 8k resolution. I applied nanite to all pieces and after I done building, I merged all actors to a single static mesh actor. When I opened the static mesh, I saw triangulate is over 1 million but I had enabled all pieces to nanite before I merge and enabled nanite to merged static actor . Also even the object has over 1 million triangulate, mesh was drastically deformed after I merged every piece. I grouped modular pieces than I copied 12 times to emulate a city, FPS count was around 50-60. Building is going to be static I mean player wont enter and step on stairs. Am I doing wrong framework? Should I model and import as complete building? Than I struggle with UVs when I make big and complex objects. Now to create a perfect city with a 60 FPS optimization what options do I have here? For now to me the best option is to create a city with modular pieces as 1080p not 8k

Well the whole idea of Nanite is that you can use a lot of high poly meshes in the scene. I wouldn’t merge them. I think Nanite works better that way.
And yeah- 8k is huge. Check if you really need 8k. Often 2k texture are bumped up to 8k so it looks better in the product description. Just see if the texture has enough detail to justify that resolution.

Hey, I used 8k because in integrated bridge, it said nanite not 8k and because I will use nanite I said my self why not :D. Probably, after I done with modular building, I will group and then I will dublicate to create a city. It looks like this is the best solution so far. Now, with UE4 I was checking LOD view mode to check how expensive that object is. Now there is an option on Nanite Virtualization but I couldn’t understand is it expensive or not. Probably, thats because already when you enable nanite, it is completely ready to go, and you don’t need to bother that static object. But when I merged I saw that over 1 million triangulate and nanite was enabled. I couldn’t believe and I checked with Nanite Visualization. Nanite was working and that’s the reason I created this question.

hey, I created a scene with two objects as 8k. I downloaded in Bridge. I enabled nanite than I only used 2 mesh and when I open their mesh editor their truangle was only 2000. I duplicated only 150 times and fps was 50-65. So I think when I merged modular pieces and in mesh editor over 1 million tringulate value had deceived me. I duplicated 12 times my building and fps count was 60. Now when I duplicate 150 times a 2000 truangulate mesh FPS was 50-65.