diff --git a/engines/ultima/ultima8/usecode/uc_list.h b/engines/ultima/ultima8/usecode/uc_list.h
index fbba166f89c..c3231925362 100644
--- a/engines/ultima/ultima8/usecode/uc_list.h
+++ b/engines/ultima/ultima8/usecode/uc_list.h
@@ -77,6 +77,14 @@ public:
 		_size++;
 	}
 
+	void appenduint16(uint16 val) {
+		assert(_elementSize == 2);
+		uint8 buf[2];
+		buf[0] = static_cast<uint8>(val);
+		buf[1] = static_cast<uint8>(val >> 8);
+		append(buf);
+	}
+
 	void remove(const uint8 *e) {
 		// do we need to erase all occurences of e or just the first one?
 		// (deleting all, currently)
@@ -105,20 +113,23 @@ public:
 	}
 
 	void appendList(const UCList &l) {
-		// need to check if elementsizes match...
+		// elementsizes should match...
+		assert(_elementSize == l.getElementSize());
 		_elements.reserve(_elementSize * (_size + l._size));
-		unsigned int lsize = l._size;
-		for (unsigned int i = 0; i < lsize; i++)
+		for (unsigned int i = 0; i < l._size; i++)
 			append(l[i]);
 	}
 	void unionList(const UCList &l) { // like append, but remove duplicates
-		// need to check if elementsizes match...
+		// elementsizes should match...
+		assert(_elementSize == l.getElementSize());
 		_elements.reserve(_elementSize * (_size + l._size));
 		for (unsigned int i = 0; i < l._size; i++)
 			if (!inList(l[i]))
 				append(l[i]);
 	}
 	void subtractList(const UCList &l) {
+		// elementsizes should match...
+		assert(_elementSize == l.getElementSize());
 		for (unsigned int i = 0; i < l._size; i++)
 			remove(l[i]);
 	}
diff --git a/engines/ultima/ultima8/world/container.cpp b/engines/ultima/ultima8/world/container.cpp
index 7a65f93b356..49c46100b76 100644
--- a/engines/ultima/ultima8/world/container.cpp
+++ b/engines/ultima/ultima8/world/container.cpp
@@ -275,10 +275,7 @@ void Container::containerSearch(UCList *itemlist, const uint8 *loopscript,
 		if ((*iter)->checkLoopScript(loopscript, scriptsize)) {
 			assert(itemlist->getElementSize() == 2);
 			uint16 oId = (*iter)->getObjId();
-			uint8 buf[2];
-			buf[0] = static_cast<uint8>(oId);
-			buf[1] = static_cast<uint8>(oId >> 8);
-			itemlist->append(buf);
+			itemlist->appenduint16(oId);
 		}
 
 		if (recurse) {
diff --git a/engines/ultima/ultima8/world/current_map.cpp b/engines/ultima/ultima8/world/current_map.cpp
index ad342033ed5..46c27da22cf 100644
--- a/engines/ultima/ultima8/world/current_map.cpp
+++ b/engines/ultima/ultima8/world/current_map.cpp
@@ -607,11 +607,7 @@ void CurrentMap::areaSearch(UCList *itemlist, const uint8 *loopscript,
 				// check item against loopscript
 				if (item->checkLoopScript(loopscript, scriptsize)) {
 					assert(itemlist->getElementSize() == 2);
-					const uint16 objid = item->getObjId();
-					uint8 buf[2];
-					buf[0] = static_cast<uint8>(objid);
-					buf[1] = static_cast<uint8>(objid >> 8);
-					itemlist->append(buf);
+					itemlist->appenduint16(item->getObjId());
 				}
 
 				if (recurse) {
@@ -696,11 +692,7 @@ void CurrentMap::surfaceSearch(UCList *itemlist, const uint8 *loopscript,
 				// check item against loopscript
 				if (item->checkLoopScript(loopscript, scriptsize)) {
 					assert(itemlist->getElementSize() == 2);
-					uint16 objid = item->getObjId();
-					uint8 buf[2];
-					buf[0] = static_cast<uint8>(objid);
-					buf[1] = static_cast<uint8>(objid >> 8);
-					itemlist->append(buf);
+					itemlist->appenduint16(item->getObjId());
 				}
 			}
 		}