diff --git a/app/components/ComponentModelStructureEditor.vue b/app/components/ComponentModelStructureEditor.vue
index 57989f4..3328261 100644
--- a/app/components/ComponentModelStructureEditor.vue
+++ b/app/components/ComponentModelStructureEditor.vue
@@ -5,13 +5,15 @@
       :depth="0"
       :component-types="availableComponentTypes"
       :piece-types="availablePieceTypes"
+      :lock-type="lockRootType"
+      :locked-type-label="displayedRootTypeLabel"
       is-root
     />
   </div>
 </template>
 
 <script setup lang="ts">
-import { reactive, watch, computed, onMounted } from 'vue'
+import { reactive, watch, computed, onMounted, ref } from 'vue'
 import StructureNodeEditor from '~/components/StructureNodeEditor.vue'
 import {
   defaultStructure,
@@ -28,11 +30,62 @@ const props = defineProps({
     type: Object,
     default: () => defaultStructure(),
   },
+  rootTypeId: {
+    type: String,
+    default: '',
+  },
+  rootTypeLabel: {
+    type: String,
+    default: '',
+  },
+  lockRootType: {
+    type: Boolean,
+    default: false,
+  },
 })
 
 const emit = defineEmits(['update:modelValue'])
 
 const localStructure = reactive(hydrateStructureForEditor(props.modelValue))
+const previousLockedLabel = ref(props.rootTypeLabel || '')
+
+const { pieceTypes, loadPieceTypes } = usePieceTypes()
+const { componentTypes, loadComponentTypes } = useComponentTypes()
+
+const availablePieceTypes = computed(() => pieceTypes.value ?? [])
+const availableComponentTypes = computed(() => componentTypes.value ?? [])
+
+const fallbackRootTypeLabel = computed(() => {
+  if (!props.rootTypeId) {
+    return ''
+  }
+  const match = availableComponentTypes.value.find((type) => type?.id === props.rootTypeId)
+  return match?.name || ''
+})
+
+const displayedRootTypeLabel = computed(() => props.rootTypeLabel || fallbackRootTypeLabel.value)
+
+const syncRootType = () => {
+  if (!props.lockRootType) {
+    previousLockedLabel.value = props.rootTypeLabel || ''
+    return
+  }
+
+  const newTypeId = props.rootTypeId || ''
+  const newLabel = displayedRootTypeLabel.value
+
+  localStructure.typeComposantId = newTypeId
+  localStructure.typeComposantLabel = newLabel
+
+  const previousLabel = previousLockedLabel.value
+  if (!localStructure.name || localStructure.name === previousLabel || localStructure.name === '') {
+    localStructure.name = newLabel || localStructure.name
+  }
+
+  previousLockedLabel.value = newLabel
+}
+
+let lastEmitted = JSON.stringify(cloneStructure(props.modelValue))
 
 const syncFromProps = (value: any) => {
   const hydrated = hydrateStructureForEditor(value)
@@ -40,6 +93,7 @@ const syncFromProps = (value: any) => {
   localStructure.pieces = hydrated.pieces
   localStructure.subComponents = hydrated.subComponents
   lastEmitted = JSON.stringify(cloneStructure(value))
+  syncRootType()
 }
 
 watch(
@@ -50,7 +104,20 @@ watch(
   { deep: true }
 )
 
-let lastEmitted = JSON.stringify(cloneStructure(props.modelValue))
+watch(
+  () => [props.rootTypeId, props.rootTypeLabel, props.lockRootType],
+  () => {
+    syncRootType()
+  },
+  { immediate: true }
+)
+
+watch(
+  availableComponentTypes,
+  () => {
+    syncRootType()
+  }
+)
 
 watch(
   localStructure,
@@ -65,12 +132,6 @@ watch(
   { deep: true }
 )
 
-const { pieceTypes, loadPieceTypes } = usePieceTypes()
-const { componentTypes, loadComponentTypes } = useComponentTypes()
-
-const availablePieceTypes = computed(() => pieceTypes.value ?? [])
-const availableComponentTypes = computed(() => componentTypes.value ?? [])
-
 onMounted(async () => {
   const loaders: Promise<any>[] = []
   if (!availablePieceTypes.value.length) {
@@ -82,5 +143,6 @@ onMounted(async () => {
   if (loaders.length) {
     await Promise.allSettled(loaders)
   }
+  syncRootType()
 })
 </script>
diff --git a/app/components/StructureNodeEditor.vue b/app/components/StructureNodeEditor.vue
index 9d3e7ba..417f7cf 100644
--- a/app/components/StructureNodeEditor.vue
+++ b/app/components/StructureNodeEditor.vue
@@ -8,25 +8,32 @@
               {{ isRoot ? 'Famille de composant racine' : 'Famille de composant' }}
             </span>
           </label>
-          <select
-            v-model="node.typeComposantId"
-            class="select select-bordered select-sm w-full"
-            @change="handleComponentTypeSelect(node)"
-          >
-            <option value="">
-              Sélectionner une famille de composant
-            </option>
-            <option
-              v-for="type in componentTypes"
-              :key="type.id"
-              :value="type.id"
+          <template v-if="!lockType">
+            <select
+              v-model="node.typeComposantId"
+              class="select select-bordered select-sm w-full"
+              @change="handleComponentTypeSelect(node)"
             >
-              {{ formatComponentTypeOption(type) }}
-            </option>
-          </select>
-          <p class="text-[11px] text-gray-500">
-            {{ node.typeComposantId ? `Sélection : ${getComponentTypeLabel(node.typeComposantId) || 'Inconnue'}` : 'Aucune famille sélectionnée' }}
-          </p>
+              <option value="">
+                Sélectionner une famille de composant
+              </option>
+              <option
+                v-for="type in componentTypes"
+                :key="type.id"
+                :value="type.id"
+              >
+                {{ formatComponentTypeOption(type) }}
+              </option>
+            </select>
+            <p class="text-[11px] text-gray-500">
+              {{ node.typeComposantId ? `Sélection : ${getComponentTypeLabel(node.typeComposantId) || 'Inconnue'}` : 'Aucune famille sélectionnée' }}
+            </p>
+          </template>
+          <template v-else>
+            <div class="input input-bordered input-sm bg-base-200 flex items-center">
+              {{ lockedTypeDisplay }}
+            </div>
+          </template>
         </div>
         <button
           v-if="!isRoot"
@@ -202,11 +209,15 @@ const props = withDefaults(defineProps<{
   componentTypes?: ModelTypeOption[]
   pieceTypes?: ModelTypeOption[]
   isRoot?: boolean
+  lockType?: boolean
+  lockedTypeLabel?: string
 }>(), {
   depth: 0,
   componentTypes: () => [],
   pieceTypes: () => [],
   isRoot: false,
+  lockType: false,
+  lockedTypeLabel: '',
 })
 
 const emit = defineEmits(['remove'])
@@ -222,6 +233,12 @@ const containerClass = computed(() => {
 })
 
 const headingClass = computed(() => (props.isRoot ? 'text-sm font-semibold' : 'text-xs font-semibold'))
+const lockedTypeDisplay = computed(() => {
+  if (props.lockedTypeLabel) {
+    return props.lockedTypeLabel
+  }
+  return getComponentTypeLabel(props.node?.typeComposantId) || 'Famille non définie'
+})
 
 const formatModelTypeOption = (type: ModelTypeOption | undefined | null) => {
   if (!type) return ''
@@ -274,6 +291,15 @@ const syncComponentType = (component: any) => {
   if (!component) {
     return
   }
+  if (props.lockType && props.isRoot) {
+    if (props.lockedTypeLabel) {
+      component.typeComposantLabel = props.lockedTypeLabel
+      if (!component.name || component.name === component.typeComposantLabel) {
+        component.name = props.lockedTypeLabel
+      }
+    }
+    return
+  }
   const id = typeof component.typeComposantId === 'string'
     ? component.typeComposantId
     : ''
@@ -430,4 +456,18 @@ watch(
   },
   { deep: true }
 )
+
+watch(
+  () => [props.lockedTypeLabel, props.lockType],
+  () => {
+    if (props.lockType && props.isRoot) {
+      const label = props.lockedTypeLabel || lockedTypeDisplay.value
+      props.node.typeComposantLabel = label
+      if (label && (!props.node.name || props.node.name === lockedTypeDisplay.value)) {
+        props.node.name = label
+      }
+    }
+  },
+  { immediate: true }
+)
 </script>
diff --git a/app/pages/component-catalog.vue b/app/pages/component-catalog.vue
index 0308ed9..a678a18 100644
--- a/app/pages/component-catalog.vue
+++ b/app/pages/component-catalog.vue
@@ -180,7 +180,12 @@
             <div class="divider my-0">
               Structure
             </div>
-            <ComponentModelStructureEditor v-model="form.data.structure" />
+            <ComponentModelStructureEditor
+              v-model="form.data.structure"
+              :root-type-id="form.data.typeComposantId"
+              :root-type-label="selectedComponentTypeLabel"
+              :lock-root-type="!!form.data.typeComposantId"
+            />
             <div class="rounded-lg border border-base-200 bg-base-200/60 p-3 text-xs text-gray-500">
               Aperçu : {{ formatStructurePreview(form.data.structure) }}
             </div>
@@ -292,6 +297,21 @@ const filteredModels = computed(() => {
   })
 })
 
+const selectedComponentType = computed(() => {
+  if (!form.data.typeComposantId) {
+    return null
+  }
+  return componentTypes.value.find((type) => type.id === form.data.typeComposantId) || null
+})
+
+const selectedComponentTypeLabel = computed(() => {
+  const type = selectedComponentType.value
+  if (!type) {
+    return ''
+  }
+  return type.code ? `${type.name} (${type.code})` : type.name
+})
+
 const refreshModels = async () => {
   if (selectedType.value === 'all') {
     await loadComponentModels()