If you’re using RayTraced Distance Field shadows, I think depending on the mesh construction that you should only need to increase the Distance Field Resolution in the Build Settings of the Static Mesh Editor.
When distance fields are generated they will generate a mesh that is representative of the graphics mesh which you view with Visualize > Mesh Distance Fields. This generated mesh will also not be 100% accurate, so for sharp edges on a box or wall it can produce rounded corners. The larger the mesh the more rounded the corners will be and will need to be increased.
As an example here is a simple mesh I made:
This is the mesh:
Default Distance Field Resolution of 1.0:
Distance Field Resolution of 5.0:
You can change the DF Resolution in the Static Mesh Editor under the LOD0 settings here:
As the Distance Field Resolution is increased this can produce better results. The main thing to keep in mind is that Distance Fields are meant for modular assets and not for large geometry so if you break the mesh into smaller pieces it can produce better results.
From your image from your original post, and even with the mesh distance field view it’s hard to tell exactly for sureabout the quality, but looking at the mesh in the front where you’ve got the door ways that is one continuous mesh and you can see the rounding in the corners, which can be an issue for shadowing if you didn’t have the door there to block light because this rounded mesh will be used for the shadowing which wouldn’t be accurate to what the grahics mesh looks like.