Lighting revealing seams

[GreatBuzzard2844]

Hello,

I am having issues with unreal engine 5’s lighting revealing the seams of my meshes. I am a little worried it is because i created the entire map out of individual tiles, such as the floor is made of lots of 3x3m tiles and the wall is 4x3m and i have read somewhere than unreal engine will calculate the light differently on every face revealing the seams. i have tried merging every part of my map together but it still reveals seams. In unlit mode my walls and floors are completely seamless. Could someone please help and suggest possible fixes? i am pretty new to unreal engine so might need to explain how to do stuff.

Also in this image you can see im using a rect light but only part of the floor is being lit up which i find strange, the dark part only lights up if i place the light directly above it. Could be linked to the main problem im having im not sure.

Any help appreciated!!!

[McMillJon]

Hey @GreatBuzzard2844 since the seams disappear in Unlit mode, this points to a lighting or shading issue rather than the geometry itself. However, it could also be a material problem. Check whether the seams are visible in the Base Colour, Normal, Roughness, or AO texture maps individually. If the textures tile correctly and the seams only appear in Lit mode, I’d investigate Lumen, shadow settings, or mesh normals/smoothing groups first. The Rect Light only affecting part of the floor also suggests a lighting setup issue rather than a texture issue. Does it do the same when using other lights. I’m assuming it does but doesn’t hurt to check.
Let me know how you go!