diff --git a/noisemap-core/src/main/java/org/orbisgis/noisemap/core/FastObstructionTest.java b/noisemap-core/src/main/java/org/orbisgis/noisemap/core/FastObstructionTest.java
index 2f3bde785..bfe20c9ad 100644
--- a/noisemap-core/src/main/java/org/orbisgis/noisemap/core/FastObstructionTest.java
+++ b/noisemap-core/src/main/java/org/orbisgis/noisemap/core/FastObstructionTest.java
@@ -483,7 +483,7 @@ public List<Coordinate> getWideAnglePoints(double minAngle, double maxAngle) {
      * @return List of segment
      */
     public LinkedList<Wall> getLimitsInRange(double maxDist,
-                                                    Coordinate p1) {
+                                                    Coordinate p1, boolean goThroughWalls) {
         LinkedList<Wall> walls = new LinkedList<>();
         int curTri = getTriangleIdByCoordinate(p1);
         int nextTri = -1;
@@ -526,7 +526,7 @@ public LinkedList<Wall> getLimitsInRange(double maxDist,
                         if (wall.getBuildingId() >= 1) {
                             walls.add(wall);
                         }
-                        if(!navigationHistory.contains(neighbors.get(sideId))) {
+                        if((goThroughWalls || wall.getBuildingId() < 1) && !navigationHistory.contains(neighbors.get(sideId))) {
                             // Store currentTriangle Id. This is where to go
                             // back when there is no more navigable neighbors at
                             // the next triangle
diff --git a/noisemap-core/src/main/java/org/orbisgis/noisemap/core/PropagationProcess.java b/noisemap-core/src/main/java/org/orbisgis/noisemap/core/PropagationProcess.java
index 79c0d406b..4a599b82b 100644
--- a/noisemap-core/src/main/java/org/orbisgis/noisemap/core/PropagationProcess.java
+++ b/noisemap-core/src/main/java/org/orbisgis/noisemap/core/PropagationProcess.java
@@ -141,7 +141,7 @@ private void feedMirroredReceiverResults(
                 //Counter ClockWise test. Walls vertices are CCW oriented.
                 //This help to test if a wall could see a point or another wall
                 //If the triangle formed by two point of the wall + the receiver is CCW then the wall is oriented toward the point.
-                boolean isCCW = false;
+                boolean isCCW;
                 if (lastResult == -1) { //If the receiverCoord is not an image
                     isCCW = wallPointTest(wall, receiverCoord);
                 } else {
@@ -981,10 +981,8 @@ public void computeSoundLevelAtPosition(Coordinate receiverCoord, double energet
         double srcEnergeticSum = BASE_LVL; //Global energetic sum of all sources processed
         List<FastObstructionTest.Wall> nearBuildingsWalls = null;
         if (data.reflexionOrder > 0) {
-            nearBuildingsWalls = new ArrayList<>(
-                    data.freeFieldFinder.getLimitsInRange(
-                            data.maxSrcDist, receiverCoord)
-            );
+            nearBuildingsWalls = new ArrayList<>(data.freeFieldFinder.getLimitsInRange(
+                            data.maxSrcDist, receiverCoord, false));
         }
         // Source search by multiple range query
         HashSet<Integer> processedLineSources = new HashSet<Integer>(); //Already processed Raw source (line and/or points)