diff --git a/Tactical/LOS.cpp b/Tactical/LOS.cpp
index 1ec0e7ef..ccda925e 100644
--- a/Tactical/LOS.cpp
+++ b/Tactical/LOS.cpp
@@ -1935,9 +1935,9 @@ INT32 LineOfSightTest( FLOAT dStartX, FLOAT dStartY, FLOAT dStartZ, FLOAT dEndX,
 
 		// leaving a tile, check to see if it had gas in it
 		//		if ( pMapElement->ubExtFlags[0] & (MAPELEMENT_EXT_SMOKE | MAPELEMENT_EXT_TEARGAS | MAPELEMENT_EXT_MUSTARDGAS) )
-		if ( pMapElement->ubExtFlags[0] & (MAPELEMENT_EXT_SMOKE | MAPELEMENT_EXT_TEARGAS | MAPELEMENT_EXT_MUSTARDGAS | MAPELEMENT_EXT_BURNABLEGAS) )
+		if ( pMapElement->ubExtFlags[0] & (MAPELEMENT_EXT_SMOKE | MAPELEMENT_EXT_TEARGAS | MAPELEMENT_EXT_MUSTARDGAS | MAPELEMENT_EXT_BURNABLEGAS | MAPELEMENT_EXT_DEBRIS_SMOKE) )
 		{
-			if ( (pMapElement->ubExtFlags[0] & MAPELEMENT_EXT_SMOKE) && !fSmell )
+			if ( (pMapElement->ubExtFlags[0] & (MAPELEMENT_EXT_SMOKE | MAPELEMENT_EXT_DEBRIS_SMOKE) ) && !fSmell )
 			{
 				bSmoke++;
 
diff --git a/Tactical/Overhead.cpp b/Tactical/Overhead.cpp
index ff4bde3b..fdd07bf3 100644
--- a/Tactical/Overhead.cpp
+++ b/Tactical/Overhead.cpp
@@ -2387,6 +2387,14 @@ BOOLEAN HandleGotoNewGridNo( SOLDIERTYPE *pSoldier, BOOLEAN *pfKeepMoving, BOOLE
                         }
                     }
 
+					if ( gpWorldLevelData[pSoldier->sGridNo].ubExtFlags[pSoldier->pathing.bLevel] & MAPELEMENT_EXT_DEBRIS_SMOKE )
+					{
+						//if ( !(pSoldier->flags.fHitByGasFlags & HIT_BY_BURNABLEGAS) )	// gas mask doesn't help vs fire damage
+						{
+							pExplosive = &(Explosive[Item[GetFirstExplosiveOfType( EXPLOSV_SMOKE_DEBRIS )].ubClassIndex]);
+						}
+					}
+
                     //ScreenMsg( FONT_MCOLOR_LTYELLOW, MSG_INTERFACE, L"Overhead pSoldier->flags.fHitByGasFlags: %d", pSoldier->flags.fHitByGasFlags );
                     //ScreenMsg( FONT_MCOLOR_LTYELLOW, MSG_INTERFACE, L"Overhead pExplosive: %d", pExplosive->ubType );
 
diff --git a/Tactical/Weapons.h b/Tactical/Weapons.h
index a79d471a..3fed58f8 100644
--- a/Tactical/Weapons.h
+++ b/Tactical/Weapons.h
@@ -291,6 +291,7 @@ enum
 	EXPLOSV_BURNABLEGAS,
 	EXPLOSV_FLASHBANG,
 	EXPLOSV_SIGNAL_SMOKE,
+	EXPLOSV_SMOKE_DEBRIS,
 };
 
 #define AMMO_DAMAGE_ADJUSTMENT_BUCKSHOT( x ) (x / 4)
diff --git a/TacticalAI/AIUtils.cpp b/TacticalAI/AIUtils.cpp
index 1b96a032..a78d69b3 100644
--- a/TacticalAI/AIUtils.cpp
+++ b/TacticalAI/AIUtils.cpp
@@ -1961,7 +1961,7 @@ BOOLEAN InWaterGasOrSmoke( SOLDIERTYPE *pSoldier, INT32 sGridNo )
 BOOLEAN InGasOrSmoke( SOLDIERTYPE *pSoldier, INT32 sGridNo )
 {
 	// smoke
-	if (gpWorldLevelData[sGridNo].ubExtFlags[ pSoldier->pathing.bLevel ] & (MAPELEMENT_EXT_SMOKE|MAPELEMENT_EXT_SIGNAL_SMOKE) )	
+	if ( gpWorldLevelData[sGridNo].ubExtFlags[pSoldier->pathing.bLevel] & (MAPELEMENT_EXT_SMOKE | MAPELEMENT_EXT_SIGNAL_SMOKE | MAPELEMENT_EXT_DEBRIS_SMOKE) )
 		return TRUE;
 
 	return InGas(pSoldier,sGridNo);
diff --git a/TacticalAI/Attacks.cpp b/TacticalAI/Attacks.cpp
index eddac550..f980b7cb 100644
--- a/TacticalAI/Attacks.cpp
+++ b/TacticalAI/Attacks.cpp
@@ -1179,7 +1179,7 @@ void CalcBestThrow(SOLDIERTYPE *pSoldier, ATTACKTYPE *pBestThrow)
 					//					if ( gpWorldLevelData[ sGridNo ].ubExtFlags[ bOpponentLevel[ubLoop] ] & MAPELEMENT_EXT_SMOKE ||
 					//						gpWorldLevelData[ sGridNo ].ubExtFlags[ bOpponentLevel[ubLoop] ] & (MAPELEMENT_EXT_TEARGAS | MAPELEMENT_EXT_MUSTARDGAS) ||
 					//						gpWorldLevelData[ sGridNo ].ubExtFlags[ bOpponentLevel[ubLoop] ] & MAPELEMENT_EXT_MUSTARDGAS)
-					if ( gpWorldLevelData[ sGridNo ].ubExtFlags[ bOpponentLevel[ubLoop] ] & MAPELEMENT_EXT_SMOKE ||
+					if ( gpWorldLevelData[sGridNo].ubExtFlags[bOpponentLevel[ubLoop]] & (MAPELEMENT_EXT_SMOKE | MAPELEMENT_EXT_DEBRIS_SMOKE) ||
 						gpWorldLevelData[ sGridNo ].ubExtFlags[ bOpponentLevel[ubLoop] ] & (MAPELEMENT_EXT_TEARGAS | MAPELEMENT_EXT_MUSTARDGAS | MAPELEMENT_EXT_BURNABLEGAS) ||
 						gpWorldLevelData[ sGridNo ].ubExtFlags[ bOpponentLevel[ubLoop] ] & MAPELEMENT_EXT_MUSTARDGAS || gpWorldLevelData[ sGridNo ].ubExtFlags[ bOpponentLevel[ubLoop] ] & MAPELEMENT_EXT_BURNABLEGAS)
 					{
@@ -2107,7 +2107,7 @@ INT32 EstimateThrowDamage( SOLDIERTYPE *pSoldier, UINT8 ubItemPos, SOLDIERTYPE *
 		else
 			return(0);
 	}
-	else if ( Explosive[Item[pSoldier->inv[ ubItemPos ].usItem].ubClassIndex].ubType == EXPLOSV_SMOKE )
+	else if ( Explosive[Item[pSoldier->inv[ubItemPos].usItem].ubClassIndex].ubType == EXPLOSV_SMOKE || Explosive[Item[pSoldier->inv[ubItemPos].usItem].ubClassIndex].ubType == EXPLOSV_SMOKE_DEBRIS )
 		return 5;
 	else
 		ubExplosiveIndex = Item[ pSoldier->inv[ubItemPos].usItem ].ubClassIndex;
diff --git a/TileEngine/Explosion Control.cpp b/TileEngine/Explosion Control.cpp
index 041252fd..8c7db117 100644
--- a/TileEngine/Explosion Control.cpp	
+++ b/TileEngine/Explosion Control.cpp	
@@ -1986,7 +1986,7 @@ BOOLEAN DishOutGasDamage( SOLDIERTYPE * pSoldier, EXPLOSIVETYPE * pExplosive, IN
 			}
 
 		}
-		else if(pExplosive->ubType == EXPLOSV_SMOKE)//dnl ch40 200909
+		else if ( pExplosive->ubType == EXPLOSV_SMOKE || pExplosive->ubType == EXPLOSV_SMOKE_DEBRIS )//dnl ch40 200909
 		{
 			// robots are unaffected by smoke
 			if( AM_A_ROBOT(pSoldier) )
@@ -2092,6 +2092,7 @@ BOOLEAN DishOutGasDamage( SOLDIERTYPE * pSoldier, EXPLOSIVETYPE * pExplosive, IN
 			pSoldier->flags.fHitByGasFlags |= HIT_BY_BURNABLEGAS;
 			break;
 		case EXPLOSV_SMOKE://dnl ch40 200909
+		case EXPLOSV_SMOKE_DEBRIS:
 			pSoldier->flags.fHitByGasFlags |= HIT_BY_SMOKEGAS;
 			break;
 		default:
@@ -2224,6 +2225,12 @@ BOOLEAN ExpAffect( INT32 sBombGridNo, INT32 sGridNo, UINT32 uiDist, UINT16 usIte
 			bSmokeEffectType = SIGNAL_SMOKE_EFFECT;
 			fBlastEffect	= FALSE;
 			break;
+
+		case EXPLOSV_SMOKE_DEBRIS:
+			fSmokeEffect = TRUE;
+			bSmokeEffectType = DEBRIS_SMOKE_EFFECT;
+			fBlastEffect = FALSE;
+			break;
 		}
 	}
 
@@ -2904,6 +2911,7 @@ void SpreadEffect( INT32 sGridNo, UINT8 ubRadius, UINT16 usItem, UINT8 ubOwner,
 	case EXPLOSV_SMOKE:
 	case EXPLOSV_CREATUREGAS:
 	case EXPLOSV_SIGNAL_SMOKE:
+	case EXPLOSV_SMOKE_DEBRIS:
 
 		fSmokeEffect = TRUE;
 		break;
@@ -5956,6 +5964,16 @@ void RoofDestruction( INT32 sGridNo, BOOLEAN fWithExplosion )
 		{
 			InternalIgniteExplosion( NOBODY, CenterX( sGridNo ), CenterY( sGridNo ), 0, sGridNo, usRoofCollapseExplosionIndex, FALSE, 0 );
 		}
+
+		if ( Chance( 15 ) )
+		{
+			static UINT16 debrissmokeitem = GetFirstExplosiveOfType( EXPLOSV_SMOKE_DEBRIS );
+
+			if ( debrissmokeitem )
+			{
+				InternalIgniteExplosion( NOBODY, CenterX( sGridNo ), CenterY( sGridNo ), 0, sGridNo, debrissmokeitem, FALSE, 0 );
+			}
+		}
 	}
 
 	RemoveAllRoofsOfTypeRangeAdjustSaveFile( sGridNo, FIRSTTEXTURE, WIREFRAMES );
@@ -6043,26 +6061,29 @@ void HandleRoofDestruction( INT32 sGridNo, INT16 sDamage )
 		// sadly the calculating time is somewhat high if there are many nodes connected to the roof, like Alma prison.
 		// therefore this part is commented out. Can be commented in once the speed issues have been resolved
 		// properly done, this would simulat the 'structural integrity' of the building
-		/*// for each remaining node, determine the distance to the closest node with a wall-connection inside the remaining network. If the distance is high enough, the roof will come down
+		// for each remaining node, determine the distance to the closest node with a wall-connection inside the remaining network. If the distance is high enough, the roof will come down
 		gridnoarmourvector roofarmoursharednetwork = GetArmourSharedRoofNetwork( (*roofnetworkit).second );
 
-		for ( gridnoarmourvector::iterator it = roofarmoursharednetwork.begin( ); it != roofarmoursharednetwork.end( ); ++it )
+		if ( roofarmoursharednetwork.size() < 200 )
 		{
-		gridnoarmourpair pair = (*it);
+			for ( gridnoarmourvector::iterator it = roofarmoursharednetwork.begin( ); it != roofarmoursharednetwork.end( ); ++it )
+			{
+				gridnoarmourpair pair = (*it);
 
-		// if it does not have a roof, ignore
-		if ( !IsRoofPresentAtGridNo( pair.first ) )
-		{
-		pair.second = 0;
-		continue;
-		}
+				// if it does not have a roof, ignore
+				if ( !IsRoofPresentAtGridNo( pair.first ) )
+				{
+					pair.second = 0;
+					continue;
+				}
 
-		if ( pair.second < 1 )
-		{
-		if ( DamageRoof(  pair.first, 255 ) )
-		pair.second = 0;
+				if ( pair.second < 1 )
+				{
+					if ( DamageRoof(  pair.first, 255 ) )
+						pair.second = 0;
+				}
+			}
 		}
-		}*/
 
 		// for now, determine the best armour for each remaining network, and collapse it if there is no armou - and thus no wall connection - left
 		gridnoarmourvector roofnetwork = (*roofnetworkit).second;
diff --git a/TileEngine/Explosion Control.h b/TileEngine/Explosion Control.h
index 525188e7..610c5a45 100644
--- a/TileEngine/Explosion Control.h	
+++ b/TileEngine/Explosion Control.h	
@@ -59,6 +59,7 @@ enum EXPLOSION_TYPES
 	THERMOBARIC_EXP,
 	FLASHBANG_EXP,		// Lesh: enum added
 	ROOF_COLLAPSE,		// Flugente: play an animation of roof tiles crashing down
+	ROOF_COLLAPSE_SMOKE,	// Flugente: when structure collapses, smoke might rise
 	NUM_EXP_TYPES=50
 
 } ;
diff --git a/TileEngine/SmokeEffects.cpp b/TileEngine/SmokeEffects.cpp
index ed8b0310..c9ab8f38 100644
--- a/TileEngine/SmokeEffects.cpp
+++ b/TileEngine/SmokeEffects.cpp
@@ -130,10 +130,12 @@ INT8 FromWorldFlagsToSmokeType( UINT16 ubWorldFlags )
 	{
 		return( SIGNAL_SMOKE_EFFECT );
 	}
-	else
+	else if ( ubWorldFlags & MAPELEMENT_EXT_DEBRIS_SMOKE )
 	{
-		return( NO_SMOKE_EFFECT );
+		return(DEBRIS_SMOKE_EFFECT);
 	}
+	
+	return(NO_SMOKE_EFFECT);
 }
 
 
@@ -171,6 +173,10 @@ UINT16 FromSmokeTypeToWorldFlags( INT8 bType )
 			return( MAPELEMENT_EXT_SIGNAL_SMOKE );
 			break;
 
+		case DEBRIS_SMOKE_EFFECT:
+			return(MAPELEMENT_EXT_DEBRIS_SMOKE);
+			break;
+
 		default:
 
 			return( 0 );
@@ -275,6 +281,10 @@ INT32 NewSmokeEffect( INT32 sGridNo, UINT16 usItem, INT8 bLevel, UINT8 ubOwner,
 
 			bSmokeEffectType = SIGNAL_SMOKE_EFFECT;
 			break;
+
+		case EXPLOSV_SMOKE_DEBRIS:
+			bSmokeEffectType = DEBRIS_SMOKE_EFFECT;
+			break;
 	}
 
 	pSmoke->ubDuration	= (UINT8)Explosive[ Item[ usItem ].ubClassIndex ].ubDuration;
@@ -496,6 +506,24 @@ void AddSmokeEffectToTile( INT32 iSmokeEffectID, INT8 bType, INT32 sGridNo, INT8
 				}
 			}
 			break;
+
+		case DEBRIS_SMOKE_EFFECT:
+			if ( !(gGameSettings.fOptions[TOPTION_ANIMATE_SMOKE]) )
+			{
+				strcpy( AniParams.zCachedFile, "TILECACHE\\debris_smoke.STI" );
+			}
+			else
+			{
+				if ( fDissipating )
+				{
+					strcpy( AniParams.zCachedFile, "TILECACHE\\debris_smoke.STI" );
+				}
+				else
+				{
+					strcpy( AniParams.zCachedFile, "TILECACHE\\debris_smoke.STI" );
+				}
+			}
+			break;
 	}
 
 	// Create tile...
diff --git a/TileEngine/SmokeEffects.h b/TileEngine/SmokeEffects.h
index 9dd173f0..8cec4bc4 100644
--- a/TileEngine/SmokeEffects.h
+++ b/TileEngine/SmokeEffects.h
@@ -12,6 +12,7 @@ enum
 	CREATURE_SMOKE_EFFECT,
 	BURNABLEGAS_SMOKE_EFFECT,
 	SIGNAL_SMOKE_EFFECT,		// added by Flugente for artillery
+	DEBRIS_SMOKE_EFFECT,		// added by Flugente for collapsing roofs
 };
 
 #define SMOKE_EFFECT_INDOORS			0x01
diff --git a/TileEngine/Tile Animation.cpp b/TileEngine/Tile Animation.cpp
index f97a9311..8b25570c 100644
--- a/TileEngine/Tile Animation.cpp	
+++ b/TileEngine/Tile Animation.cpp	
@@ -570,10 +570,8 @@ void UpdateAniTiles( )
 
 							ubExpType = Explosive[ Item[ (UINT16)pNode->uiUserData ].ubClassIndex ].ubType;
 
-							//				if ( ubExpType == EXPLOSV_TEARGAS || ubExpType == EXPLOSV_MUSTGAS ||
-							//					ubExpType == EXPLOSV_SMOKE )
 							if ( ubExpType == EXPLOSV_TEARGAS || ubExpType == EXPLOSV_MUSTGAS ||
-								ubExpType == EXPLOSV_SMOKE || ubExpType == EXPLOSV_BURNABLEGAS || ubExpType == EXPLOSV_SIGNAL_SMOKE )
+								 ubExpType == EXPLOSV_SMOKE || ubExpType == EXPLOSV_BURNABLEGAS || ubExpType == EXPLOSV_SIGNAL_SMOKE || ubExpType == EXPLOSV_SMOKE_DEBRIS )
 							{
 								// Do sound....
 								// PlayJA2Sample( AIR_ESCAPING_1, RATE_11025, SoundVolume( HIGHVOLUME, pNode->sGridNo ), 1, SoundDir( pNode->sGridNo ) );
diff --git a/TileEngine/worlddef.h b/TileEngine/worlddef.h
index 0fdb6094..566198c3 100644
--- a/TileEngine/worlddef.h
+++ b/TileEngine/worlddef.h
@@ -135,12 +135,13 @@ class SOLDIERTYPE;
 #define MAPELEMENT_EXT_BURNABLEGAS					0x0100 //0x100
 #define MAPELEMENT_EXT_CLIMBPOINT					0x0200 //0x200
 #define MAPELEMENT_EXT_SIGNAL_SMOKE					0x0400 //0x400	// added by Flugente
+#define MAPELEMENT_EXT_DEBRIS_SMOKE					0x0800 //0x800	// added by Flugente
 
 #define FIRST_LEVEL 0
 #define SECOND_LEVEL 1
 
 //#define ANY_SMOKE_EFFECT		( MAPELEMENT_EXT_CREATUREGAS | MAPELEMENT_EXT_SMOKE | MAPELEMENT_EXT_TEARGAS | MAPELEMENT_EXT_MUSTARDGAS )
-#define ANY_SMOKE_EFFECT		( MAPELEMENT_EXT_CREATUREGAS | MAPELEMENT_EXT_SMOKE | MAPELEMENT_EXT_TEARGAS | MAPELEMENT_EXT_MUSTARDGAS | MAPELEMENT_EXT_BURNABLEGAS | MAPELEMENT_EXT_SIGNAL_SMOKE )
+#define ANY_SMOKE_EFFECT		( MAPELEMENT_EXT_CREATUREGAS | MAPELEMENT_EXT_SMOKE | MAPELEMENT_EXT_TEARGAS | MAPELEMENT_EXT_MUSTARDGAS | MAPELEMENT_EXT_BURNABLEGAS | MAPELEMENT_EXT_SIGNAL_SMOKE | MAPELEMENT_EXT_DEBRIS_SMOKE )
 
 
 // WDS - Clean up inventory handling