diff --git a/packaging/mother/geodesic-dome-mcp b/packaging/mother/geodesic-dome-mcp
index 3b5fa7e..7d962d1 100755
--- a/packaging/mother/geodesic-dome-mcp
+++ b/packaging/mother/geodesic-dome-mcp
@@ -200,6 +200,97 @@ def analyze_structure(verts, edges, triangles, radius_meters=5.0):
     }
 
 
+def analyze_strut_constraint(struts, max_length=2.0, bar_length=6.0):
+    """Enforce 2m max strut length for FI12 rebar (6m bars → 3× 2m cuts)."""
+    pieces_per_bar = int(bar_length / max_length)  # 3 pieces of 2m
+    over = []
+    ok = []
+    total_bars = 0
+    total_waste_m = 0.0
+
+    for s in struts:
+        L = s["length_m"]
+        count = s["count"]
+        if L > max_length:
+            over.append({"length_m": L, "count": count, "excess_m": round(L - max_length, 2)})
+        else:
+            ok.append(s)
+
+    # Calculate rebar bars needed and waste
+    total_pieces = sum(s["count"] for s in struts)
+    total_bars = math.ceil(total_pieces / pieces_per_bar)
+    total_cut_m = total_bars * bar_length
+    total_strut_m_needed = sum(s["length_m"] * s["count"] for s in struts)
+    total_waste_m = round(total_cut_m - total_strut_m_needed, 2)
+    waste_pieces = total_bars * pieces_per_bar - total_pieces
+
+    return {
+        "max_strut_length_m": max_length,
+        "bar_length_m": bar_length,
+        "pieces_per_bar": pieces_per_bar,
+        "struts_over_limit": over,
+        "struts_ok": len(ok),
+        "total_pieces_needed": total_pieces,
+        "rebar_bars_needed": total_bars,
+        "total_bar_meters": round(total_bars * bar_length, 1),
+        "waste_meters": total_waste_m,
+        "waste_pieces": waste_pieces,
+        "waste_use": "corner hardening gussets" if waste_pieces > 0 else "none",
+        "compliant": len(over) == 0,
+    }
+
+
+def construction_layers(verts, triangles, radius):
+    """Group triangles into construction layers ordered top-to-bottom.
+    
+    Welding sequence: start at apex (highest Z), weld that layer,
+    lift the completed section, weld the next layer underneath.
+    """
+    # Compute centroid Z for each triangle
+    tri_zs = []
+    for idx, (v0, v1, v2) in enumerate(triangles):
+        z = (verts[v0][2] + verts[v1][2] + verts[v2][2]) / 3 * radius
+        tri_zs.append((z, idx))
+
+    # Sort top-to-bottom (descending Z)
+    tri_zs.sort(key=lambda x: -x[0])
+
+    # Group into layers by Z proximity (every 0.5m drop = new layer)
+    layers = []
+    current_layer = []
+    current_z = None
+    layer_threshold = 0.5  # meters
+
+    for z, idx in tri_zs:
+        if current_z is None:
+            current_z = z
+        if abs(z - current_z) > layer_threshold:
+            layers.append({
+                "layer": len(layers) + 1,
+                "height_m": round(current_z, 2),
+                "triangles": len(current_layer),
+                "sequence": "weld → lift → next layer" if len(layers) > 0 else "start at apex",
+            })
+            current_layer = []
+            current_z = z
+        current_layer.append(idx)
+
+    if current_layer:
+        layers.append({
+            "layer": len(layers) + 1,
+            "height_m": round(current_z, 2),
+            "triangles": len(current_layer),
+            "sequence": "weld → lift → next layer" if len(layers) > 0 else "start at apex",
+        })
+
+    return {
+        "total_layers": len(layers),
+        "construction_method": "top-to-bottom welding, lift after each layer",
+        "layer_threshold_m": layer_threshold,
+        "layers": layers,
+    }
+
+
 def render(verts, edges, size=2048, yaw=0.3, pitch=0.4,
            line_color="#00b4d8", bg_color="#0d1117", lw=1):
     sy, cy = math.sin(yaw), math.cos(yaw)
@@ -259,6 +350,14 @@ def generate(params):
     analysis["frequency"] = freq
     analysis["half_sphere"] = half
 
+    # ── Strut constraint: 2m max (FI12 rebar, 6m bars → 3× 2m cuts) ──
+    strut_constraint = analyze_strut_constraint(analysis["struts"], max_length=2.0, bar_length=6.0)
+    analysis["strut_constraint"] = strut_constraint
+
+    # ── Construction layers: order triangles top-to-bottom for welding ──
+    layers = construction_layers(verts, triangles, radius)
+    analysis["construction_layers"] = layers
+
     result = {"success": True, "analysis": analysis}
 
     if not analysis_only: