diff --git a/ui/src/views/compute/DeployVM.vue b/ui/src/views/compute/DeployVM.vue
index 990d2eadeca..7109b9b4f1b 100644
--- a/ui/src/views/compute/DeployVM.vue
+++ b/ui/src/views/compute/DeployVM.vue
@@ -1133,7 +1133,9 @@ export default {
         this.vm.hostname = host.name
       }
 
-      if (this.diskSize) {
+      if (this.serviceOffering.rootdisksize) {
+        this.vm.disksizetotalgb = this.serviceOffering.rootdisksize
+      } else if (this.diskSize) {
         this.vm.disksizetotalgb = this.diskSize
       }