Modeling · Beginner

Solidify modifier

A modifier that gives a flat or open surface an even, adjustable thickness

Also called Solidify

What is the solidify modifier?

The solidify modifier gives a flat or open surface real thickness by building a second, offset layer and joining the edges. A single plane becomes a board, and a hollow shape gets walls. It stays adjustable, so you can change the thickness any time before applying it.

Think of it like this

Like backing a paper cut-out with foam board: the shape stays the same, but now it has an edge you can see and hold.

Where it fits in a 3D project

  1. Create
  2. Surface
  3. Rig
  4. Animate
  5. Render
  6. Export

Create: Building the shape: modeling, sculpting, scanning or generating it.

How the solidify modifier works

  1. 01Select a surface with no thickness, such as a plane or an open shell.
  2. 02Choose Add Modifier > Generate > Solidify.
  3. 03Set Thickness; Offset decides whether it grows inward, outward or both ways.
  4. 04Turn on Even Thickness if corners look thinner than flat areas.

Solidify modifier vs extrude

PropertySolidify modifierExtrude
Adjustable laterYes, until appliedNo, it is real geometry
Works onThe whole object at onceThe selected faces or edges
ThicknessAn even shell all overWherever you pull
Best forWalls, cloth, sheets and shellsShaping new parts and detail

Use solidify when a whole surface needs an even thickness you may change later; extrude when you are shaping specific faces into new forms.

Where the solidify modifier is used

  • Turning planes into walls, floors and boards
  • Giving cloth, leaves and paper a visible edge
  • Making hollow models printable with real wall thickness

Beginner tip

If the result looks doubled or grows the wrong way, check the normals. Solidify grows along them, so recalculate normals outward first, or flip the sign of Offset.

Terms related to the solidify modifier

Solidify modifier FAQ

How do I add the solidify modifier in Blender?
Select the object, open the wrench tab in the Properties editor and choose Add Modifier > Generate > Solidify. Then raise Thickness until the surface has the depth you want.
How do I add thickness to a plane?
Add a solidify modifier and set its Thickness. For a quick one-off you can also extrude the faces in Edit Mode with E, but the modifier stays adjustable and keeps every part of the surface even.
Why is my solidify modifier not working?
The usual causes are a thickness too small to see, unapplied object scale that squashes it, or flipped normals that push the shell inward. Apply scale with Ctrl+A, recalculate normals, then check again.

Updated October 29, 2026 · Browse all 3D terms