diff --git a/crates/fj-kernel/src/algorithms/intersect/curve_face.rs b/crates/fj-kernel/src/algorithms/intersect/curve_face.rs
index 3dbe4a484..9e87ec130 100644
--- a/crates/fj-kernel/src/algorithms/intersect/curve_face.rs
+++ b/crates/fj-kernel/src/algorithms/intersect/curve_face.rs
@@ -150,7 +150,7 @@ where
 #[cfg(test)]
 mod tests {
     use crate::{
-        builder::CurveBuilder,
+        builder::{CurveBuilder, FaceBuilder},
         objects::{Curve, Face, Objects},
         partial::HasPartial,
     };
diff --git a/crates/fj-kernel/src/algorithms/intersect/face_face.rs b/crates/fj-kernel/src/algorithms/intersect/face_face.rs
index 3f72039e7..66b41ac30 100644
--- a/crates/fj-kernel/src/algorithms/intersect/face_face.rs
+++ b/crates/fj-kernel/src/algorithms/intersect/face_face.rs
@@ -67,7 +67,7 @@ mod tests {
 
     use crate::{
         algorithms::intersect::CurveFaceIntersection,
-        builder::CurveBuilder,
+        builder::{CurveBuilder, FaceBuilder},
         objects::{Curve, Face, Objects},
         partial::HasPartial,
     };
diff --git a/crates/fj-kernel/src/algorithms/intersect/face_point.rs b/crates/fj-kernel/src/algorithms/intersect/face_point.rs
index 007caa096..6fa3d17b9 100644
--- a/crates/fj-kernel/src/algorithms/intersect/face_point.rs
+++ b/crates/fj-kernel/src/algorithms/intersect/face_point.rs
@@ -136,6 +136,7 @@ mod tests {
 
     use crate::{
         algorithms::intersect::{face_point::FacePointIntersection, Intersect},
+        builder::FaceBuilder,
         iter::ObjectIters,
         objects::{Face, Objects},
         partial::HasPartial,
diff --git a/crates/fj-kernel/src/algorithms/intersect/ray_face.rs b/crates/fj-kernel/src/algorithms/intersect/ray_face.rs
index 9a3b873da..38201c372 100644
--- a/crates/fj-kernel/src/algorithms/intersect/ray_face.rs
+++ b/crates/fj-kernel/src/algorithms/intersect/ray_face.rs
@@ -152,6 +152,7 @@ mod tests {
             },
             transform::TransformObject,
         },
+        builder::FaceBuilder,
         iter::ObjectIters,
         objects::{Face, Objects},
         partial::HasPartial,
diff --git a/crates/fj-kernel/src/algorithms/sweep/face.rs b/crates/fj-kernel/src/algorithms/sweep/face.rs
index 181da6a69..3919832f7 100644
--- a/crates/fj-kernel/src/algorithms/sweep/face.rs
+++ b/crates/fj-kernel/src/algorithms/sweep/face.rs
@@ -84,7 +84,7 @@ mod tests {
 
     use crate::{
         algorithms::{reverse::Reverse, transform::TransformObject},
-        builder::HalfEdgeBuilder,
+        builder::{FaceBuilder, HalfEdgeBuilder},
         objects::{Face, HalfEdge, Objects, Sketch},
         partial::HasPartial,
     };
diff --git a/crates/fj-kernel/src/algorithms/triangulate/mod.rs b/crates/fj-kernel/src/algorithms/triangulate/mod.rs
index 8fc63496a..6f9579c70 100644
--- a/crates/fj-kernel/src/algorithms/triangulate/mod.rs
+++ b/crates/fj-kernel/src/algorithms/triangulate/mod.rs
@@ -84,6 +84,7 @@ mod tests {
 
     use crate::{
         algorithms::approx::{Approx, Tolerance},
+        builder::FaceBuilder,
         objects::{Face, Objects},
         partial::HasPartial,
         storage::Handle,
diff --git a/crates/fj-kernel/src/builder/face.rs b/crates/fj-kernel/src/builder/face.rs
new file mode 100644
index 000000000..41f6dc5b1
--- /dev/null
+++ b/crates/fj-kernel/src/builder/face.rs
@@ -0,0 +1,49 @@
+use fj_math::Point;
+
+use crate::{
+    objects::Cycle,
+    partial::{HasPartial, PartialFace},
+};
+
+use super::CycleBuilder;
+
+/// Builder API for [`PartialFace`]
+pub trait FaceBuilder {
+    /// Update the [`PartialFace`] with an exterior polygon
+    fn with_exterior_polygon_from_points(
+        self,
+        points: impl IntoIterator<Item = impl Into<Point<2>>>,
+    ) -> Self;
+
+    /// Update the [`PartialFace`] with an interior polygon
+    fn with_interior_polygon_from_points(
+        self,
+        points: impl IntoIterator<Item = impl Into<Point<2>>>,
+    ) -> Self;
+}
+
+impl FaceBuilder for PartialFace {
+    fn with_exterior_polygon_from_points(
+        self,
+        points: impl IntoIterator<Item = impl Into<Point<2>>>,
+    ) -> Self {
+        let surface = self.surface().expect("Need surface to create polygon");
+
+        self.with_exterior(
+            Cycle::partial()
+                .with_poly_chain_from_points(surface, points)
+                .close_with_line_segment(),
+        )
+    }
+
+    fn with_interior_polygon_from_points(
+        self,
+        points: impl IntoIterator<Item = impl Into<Point<2>>>,
+    ) -> Self {
+        let surface = self.surface().expect("Need surface to build polygon.");
+
+        self.with_interiors([Cycle::partial()
+            .with_poly_chain_from_points(surface, points)
+            .close_with_line_segment()])
+    }
+}
diff --git a/crates/fj-kernel/src/builder/mod.rs b/crates/fj-kernel/src/builder/mod.rs
index b6cf74d99..1d96e73d7 100644
--- a/crates/fj-kernel/src/builder/mod.rs
+++ b/crates/fj-kernel/src/builder/mod.rs
@@ -11,12 +11,14 @@ mod solid;
 mod curve;
 mod cycle;
 mod edge;
+mod face;
 mod vertex;
 
 pub use self::{
     curve::CurveBuilder,
     cycle::CycleBuilder,
     edge::{GlobalEdgeBuilder, HalfEdgeBuilder},
+    face::FaceBuilder,
     shell::ShellBuilder,
     sketch::SketchBuilder,
     solid::SolidBuilder,
diff --git a/crates/fj-kernel/src/builder/shell.rs b/crates/fj-kernel/src/builder/shell.rs
index ef1580478..867519507 100644
--- a/crates/fj-kernel/src/builder/shell.rs
+++ b/crates/fj-kernel/src/builder/shell.rs
@@ -5,7 +5,7 @@ use fj_math::Scalar;
 
 use crate::{
     algorithms::transform::TransformObject,
-    builder::HalfEdgeBuilder,
+    builder::{FaceBuilder, HalfEdgeBuilder},
     objects::{
         Curve, Cycle, Face, FaceSet, HalfEdge, Objects, Shell, Surface,
         SurfaceVertex, Vertex,
diff --git a/crates/fj-kernel/src/builder/sketch.rs b/crates/fj-kernel/src/builder/sketch.rs
index 7052b4a36..aad2b9620 100644
--- a/crates/fj-kernel/src/builder/sketch.rs
+++ b/crates/fj-kernel/src/builder/sketch.rs
@@ -6,6 +6,8 @@ use crate::{
     storage::Handle,
 };
 
+use super::FaceBuilder;
+
 /// API for building a [`Sketch`]
 ///
 /// Also see [`Sketch::builder`].
diff --git a/crates/fj-kernel/src/iter.rs b/crates/fj-kernel/src/iter.rs
index 3be9a3493..6708c96b1 100644
--- a/crates/fj-kernel/src/iter.rs
+++ b/crates/fj-kernel/src/iter.rs
@@ -360,7 +360,7 @@ impl<T> Iterator for Iter<T> {
 #[cfg(test)]
 mod tests {
     use crate::{
-        builder::{CurveBuilder, CycleBuilder, HalfEdgeBuilder},
+        builder::{CurveBuilder, CycleBuilder, FaceBuilder, HalfEdgeBuilder},
         objects::{
             Curve, Cycle, Face, GlobalCurve, GlobalVertex, HalfEdge, Objects,
             Shell, Sketch, Solid, SurfaceVertex, Vertex,
diff --git a/crates/fj-kernel/src/partial/objects/face.rs b/crates/fj-kernel/src/partial/objects/face.rs
index 87cf3bb23..c2dbf2a33 100644
--- a/crates/fj-kernel/src/partial/objects/face.rs
+++ b/crates/fj-kernel/src/partial/objects/face.rs
@@ -1,10 +1,8 @@
 use fj_interop::mesh::Color;
-use fj_math::Point;
 
 use crate::{
-    builder::CycleBuilder,
     objects::{Cycle, Face, Objects, Surface},
-    partial::{util::merge_options, HasPartial, MaybePartial},
+    partial::{util::merge_options, MaybePartial},
     storage::Handle,
     validate::ValidationError,
 };
@@ -56,20 +54,6 @@ impl PartialFace {
         self
     }
 
-    /// Build the [`Face`] with an exterior polygon from the provided points
-    pub fn with_exterior_polygon_from_points(
-        self,
-        points: impl IntoIterator<Item = impl Into<Point<2>>>,
-    ) -> Self {
-        let surface = self.surface().expect("Need surface to create polygon");
-
-        self.with_exterior(
-            Cycle::partial()
-                .with_poly_chain_from_points(surface, points)
-                .close_with_line_segment(),
-        )
-    }
-
     /// Build the [`Face`] with the provided interior polygons
     pub fn with_interiors(
         mut self,
@@ -80,18 +64,6 @@ impl PartialFace {
         self
     }
 
-    /// Build the [`Face`] with an interior polygon from the provided points
-    pub fn with_interior_polygon_from_points(
-        self,
-        points: impl IntoIterator<Item = impl Into<Point<2>>>,
-    ) -> Self {
-        let surface = self.surface().expect("Need surface to build polygon.");
-
-        self.with_interiors([Cycle::partial()
-            .with_poly_chain_from_points(surface, points)
-            .close_with_line_segment()])
-    }
-
     /// Build the [`Face`] with the provided color
     pub fn with_color(mut self, color: Color) -> Self {
         self.color = Some(color);
diff --git a/crates/fj-kernel/src/validate/face.rs b/crates/fj-kernel/src/validate/face.rs
index f0b0fdd81..098b5ea28 100644
--- a/crates/fj-kernel/src/validate/face.rs
+++ b/crates/fj-kernel/src/validate/face.rs
@@ -105,7 +105,7 @@ impl FaceValidationError {
 mod tests {
     use crate::{
         algorithms::reverse::Reverse,
-        builder::CycleBuilder,
+        builder::{CycleBuilder, FaceBuilder},
         objects::{Cycle, Face, Objects},
         partial::HasPartial,
         validate::Validate,
diff --git a/crates/fj-operations/src/sketch.rs b/crates/fj-operations/src/sketch.rs
index f3ebf3dbd..83ab1911c 100644
--- a/crates/fj-operations/src/sketch.rs
+++ b/crates/fj-operations/src/sketch.rs
@@ -2,7 +2,7 @@ use std::ops::Deref;
 
 use fj_interop::{debug::DebugInfo, mesh::Color};
 use fj_kernel::{
-    builder::HalfEdgeBuilder,
+    builder::{FaceBuilder, HalfEdgeBuilder},
     objects::{Cycle, Face, HalfEdge, Objects, Sketch},
     partial::HasPartial,
     validate::ValidationError,