diff --git a/floorplan/v2/FloorplanLINT.h b/floorplan/v2/FloorplanLINT.h
new file mode 100644
index 0000000..a2a840d
--- /dev/null
+++ b/floorplan/v2/FloorplanLINT.h
@@ -0,0 +1,79 @@
+#ifndef FLOORPLANLINT_H
+#define FLOORPLANLINT_H
+
+#include "Floorplan.h"
+#include "../../geo/BBox2.h"
+
+namespace Floorplan {
+
+	class LINT {
+
+	public:
+
+		static void check(IndoorMap* map) {
+
+			for (const Floor* floor : map->floors) {
+
+				// outline present?
+				if (floor->outline.empty()) {throw Exception("floor " + floor->name + " has no outline");}
+
+				// check outline
+				for (FloorOutlinePolygon* poly : floor->outline) {
+					checkOutline(floor, poly);
+				}
+
+				// check obstacles
+				for (FloorObstacle* obs : floor->obstacles) {
+					checkObstacle(floor, obs);
+				}
+
+			}
+
+		}
+
+	private:
+
+		/** check a floor's outline */
+		static void checkOutline(const Floor* floor, const FloorOutlinePolygon* poly) {
+
+			// number of points valid?
+			if (poly->poly.points.size() < 3)		{throw Exception("floor '" + floor->name + "' outline '" + poly->name + "' needs at least 3 edges");}
+			if (poly->poly.points.size() > 1024)	{throw Exception("floor '" + floor->name + "' outline '" + poly->name + "' has too many edges");}
+
+			// outline size [bbox] valid?
+			BBox2 outline;
+			for (const Point2 pt : poly->poly.points) { outline.add(pt); }
+			const Point2 size = outline.getSize();
+			if (size.x < 1.0 || size.y < 1.0) {throw Exception("floor '" + floor->name + "' outline '" + poly->name + "' seems too small");}
+
+		}
+
+		/** check walls, doors, ... */
+		static void checkObstacle(const Floor* floor, const FloorObstacle* fo) {
+
+			// line? -> check
+			const FloorObstacleLine* line = dynamic_cast<const FloorObstacleLine*>(fo);
+			if (line) {
+				const float len_m = line->from.getDistance(line->to);
+				if (len_m < 0.15) {
+					throw Exception("floor '" + floor->name + "' line-obstacle is too short: " + std::to_string(len_m) + " meter from " + line->from.asString() + " to " + line->to.asString());
+				}
+			}
+
+			// door? -> check
+			const FloorObstacleDoor* door = dynamic_cast<const FloorObstacleDoor*>(fo);
+			if (door) {
+				const float len_m = door->from.getDistance(door->to);
+				if (len_m < 0.40) {
+					throw Exception("floor '" + floor->name + "' door is too narrow: " + std::to_string(len_m) + " meter from " + door->from.asString() + " to " + door->to.asString());
+				}
+			}
+
+		}
+
+	};
+
+}
+
+
+#endif // FLOORPLANLINT_H
diff --git a/floorplan/v2/FloorplanReader.h b/floorplan/v2/FloorplanReader.h
index 5d19af6..4959145 100644
--- a/floorplan/v2/FloorplanReader.h
+++ b/floorplan/v2/FloorplanReader.h
@@ -4,6 +4,7 @@
 #include <iostream>
 
 #include "Floorplan.h"
+#include "FloorplanLINT.h"
 
 #include "../../misc/Debug.h"
 #include "../../Assertions.h"
@@ -40,6 +41,7 @@ namespace Floorplan {
 				);
 			}
 			IndoorMap* map = parse(doc);
+			Floorplan::LINT::check(map);
 			return map;
 		}
 
@@ -57,6 +59,7 @@ namespace Floorplan {
 				);
 			}
 			IndoorMap* map = parse(doc);
+			Floorplan::LINT::check(map);
 			return map;
 		}
 
@@ -431,9 +434,6 @@ namespace Floorplan {
 					poly.points.push_back(p2);
 				}
 			}
-			if (poly.points.size() < 4 || poly.points.size() > 1024) {
-				throw Exception("detected invalid outline-polygon during XML parsing");
-			}
 			return poly;
 		}
 
diff --git a/geo/BBox2.h b/geo/BBox2.h
index c4833c3..1503f01 100644
--- a/geo/BBox2.h
+++ b/geo/BBox2.h
@@ -37,7 +37,7 @@ public:
 	}
 
 	/** returns true if the bbox is not yet configured */
-	const bool isInvalid() const {
+	bool isInvalid() const {
 		return p1.x == MAX || p1.y == MAX || p2.x == MIN || p2.y == MIN;
 	}
 
@@ -47,6 +47,9 @@ public:
 	/** get the bbox's maximum */
 	const Point2& getMax() const {return p2;}
 
+	/** get the bbox's size [max-min] */
+	const Point2 getSize() const {return p2-p1;}
+
 	/** get the bbox's center point */
 	Point2 getCenter() const { return (p1+p2) / 2; }
 
diff --git a/geo/Point2.h b/geo/Point2.h
index 3b19fd7..0d94f12 100644
--- a/geo/Point2.h
+++ b/geo/Point2.h
@@ -61,6 +61,10 @@ struct Point2 {
 		return std::sqrt(dx*dx + dy*dy);
 	}
 
+	std::string asString() const {
+		return "(" + std::to_string(x) + "," + std::to_string(y) + ")";
+	}
+
 };
 
 inline void swap(Point2& p1, Point2& p2) {