Two Sided Material
Show a surface from both sides
Also known as: Two sided · Double sided material · Double-sided rendering · Back face not showing
Quick answer
To make a mesh visible from both sides in Unreal Engine, open its material, click the main material node and tick Two Sided in the Details panel. By default Unreal draws only the front of each face, so a plane, a leaf card or a single-sided wall disappears when you look at its back. Two Sided makes the engine render the back faces too, using the same material.
How to fix it
Two Sided costs more than a single-sided material because the back faces are shaded as well, so use it where you need it: planes, cloth, fences, cards and paper-thin props. For leaves and grass use the Two Sided Foliage shading model so light passes through them. For solid objects, real thickness is usually better than Two Sided, and if a whole closed mesh looks inside out the problem is flipped normals, not a missing Two Sided option.
Tools that use Two Sided Material
See also
Backface Culling
Why faces vanish when seen from behind
Flipped Normals
Faces pointing inside out
Blend Mode
How a material combines with what is behind it
Subsurface Scattering
Light entering and bouncing inside a material
Master Material
Parent material that spawns instances
Two Sided Material in Unity
Show a surface from both sides in URP and HDRP
Solidify Modifier
Adds thickness to a surface
Foliage Looks Fake or Flat
Plants that read as flat cards or have wrong lighting
Foliage Cards
Alpha-textured planes that form leaves and plants