diff --git a/src/mesh/model.js b/src/mesh/model.js
index d7275178..107acd28 100644
--- a/src/mesh/model.js
+++ b/src/mesh/model.js
@@ -589,8 +589,7 @@ mesh.model = class MeshModel extends mesh.object {
     }
 
     // find adjacent faces to clicked point/line on a face
-    find(int, action, opt) {
-        let { radians, radius } = opt;
+    find(int, action, surface) {
         let { point, face } = int;
         let { x, y, z } = point;
         let { a, b, c } = face;
@@ -599,7 +598,7 @@ mesh.model = class MeshModel extends mesh.object {
             mesh.api.log.emit("matching surface").pin();
         }, 150);
         worker.model_select({
-            id: this.id, x, y:-z, z:y, a, b, c, matrix: this.matrix, radians, radius
+            id: this.id, x, y:-z, z:y, a, b, c, matrix: this.matrix, surface
         }).then(data => {
             if (timer) {
                 clearTimeout(timer);
diff --git a/src/mesh/tool.js b/src/mesh/tool.js
index 463a6c4b..8324616d 100644
--- a/src/mesh/tool.js
+++ b/src/mesh/tool.js
@@ -158,8 +158,12 @@ mesh.tool = class MeshTool {
         return sides.map(side => this.side2face[side].filter(v => v != face)).flat();
     }
 
-    findConnectedSurface(faces, radians) {
+    findConnectedSurface(faces, radians, filterZ) {
         const found = {};
+        const norms = this.normals;
+        if (filterZ) {
+            faces = faces.filter(f => norms[f][2] >= filterZ);
+        }
         const check = faces.slice();
         for (let face of faces) {
             found[face] = 1;
@@ -168,7 +172,10 @@ mesh.tool = class MeshTool {
         // const _v2 = new Vector3();
         while (check.length) {
             const face = check.shift();
-            const norm = this.normals[face];
+            const norm = norms[face];
+            if (filterZ !== undefined && norm[2] < filterZ) {
+                continue;
+            }
             const fadj = this.getAdjacentFaces(face).filter(f => !found[f]);
             for (let f of fadj) {
                 // #1 most accurate
@@ -182,7 +189,7 @@ mesh.tool = class MeshTool {
                 //     .map((v,i) => Math.pow(norm[i] - v, 2))
                 //     .reduce((a,v) => a + v)));
                 // #3 fastest, still good
-                const fn = Math.sqrt(this.normals[f]
+                const fn = Math.sqrt(norms[f]
                     .map((v,i) => Math.pow(norm[i] - v, 2))
                     .reduce((a,v) => a + v));
                 if (fn <= radians) {
diff --git a/src/mesh/work.js b/src/mesh/work.js
index b4d800e1..f6dcb3fd 100644
--- a/src/mesh/work.js
+++ b/src/mesh/work.js
@@ -282,7 +282,8 @@ let model = {
 
     // given model and point, locate matching vertices, lines, and faces
     select(data) {
-        let { id, x, y, z, a, b, c, matrix, radians, radius } = data;
+        let { id, x, y, z, a, b, c, matrix, surface } = data;
+        let { radians, radius, filterZ } = surface;
         // translate point into mesh matrix space
         let v3 = new Vector3(x,y,z).applyMatrix4(
             core_matrix.clone().multiply(new Matrix4().fromArray(matrix)).invert()
@@ -327,7 +328,8 @@ let model = {
         // if the geometry has indexed faces and radians are set, find surface
         const tool = rec.tool;
         if (tool && tool.sides && radians) {
-            tool.findConnectedSurface(faces, radians);
+            const match = tool.findConnectedSurface(faces, radians, filterZ);
+            return { faces: match, edges, verts, point };
         }
         return { faces, edges, verts, point };
     },