the default floor is different from normal static meshs. One way to solve your issue is to modify the UV maps on the meshes using a program like blender which will remap and rescale the maps. Another option is to do into your material and use a texture coordinate node. the texture coordinate node will allow you to tile the texture one the X and or Y axis based on the input you give it. to get TexCoordinate node go into your material and right click on the graph ans search for it then you can select the node to modify the tiling information. the node will then connect to the pins on the left side of the texture. Hope this helps a bit good luck