diff --git a/src/core/MeshBVH.js b/src/core/MeshBVH.js
index 05fd6c2d..a41596a4 100644
--- a/src/core/MeshBVH.js
+++ b/src/core/MeshBVH.js
@@ -157,7 +157,7 @@ export class MeshBVH {
 		this._roots = null;
 		if ( ! options[ SKIP_GENERATION ] ) {
 
-			this._roots = buildPackedTree( geometry, options );
+			buildPackedTree( geometry, options, this );
 
 			if ( ! geometry.boundingBox && options.setBoundingBox ) {
 
diff --git a/src/core/build/buildTree.js b/src/core/build/buildTree.js
index 38e675d3..b9574199 100644
--- a/src/core/build/buildTree.js
+++ b/src/core/build/buildTree.js
@@ -142,7 +142,7 @@ function buildTree( geo, options ) {
 
 }
 
-export function buildPackedTree( geo, options ) {
+export function buildPackedTree( geo, options, target ) {
 
 	// boundingData  				: 6 float32
 	// right / offset 				: 1 uint32
@@ -168,7 +168,8 @@ export function buildPackedTree( geo, options ) {
 
 	}
 
-	return packedRoots;
+	target._roots = packedRoots;
+	return;
 
 	function countNodes( node ) {