diff --git a/EnvelopeGenerator.Domain/Entities/Envelope.cs b/EnvelopeGenerator.Domain/Entities/Envelope.cs
index 21e52a9d..5ba90338 100644
--- a/EnvelopeGenerator.Domain/Entities/Envelope.cs
+++ b/EnvelopeGenerator.Domain/Entities/Envelope.cs
@@ -5,6 +5,7 @@ using System.ComponentModel.DataAnnotations.Schema;
 using EnvelopeGenerator.Domain.Constants;
 using Newtonsoft.Json;
 using EnvelopeGenerator.Domain.Interfaces.Auditing;
+using EnvelopeGenerator.Domain.Interfaces;
 #if NETFRAMEWORK
 using System.Collections.Generic;
 using System.Linq;
@@ -13,7 +14,7 @@ using System.Linq;
 namespace EnvelopeGenerator.Domain.Entities
 {
     [Table("TBSIG_ENVELOPE", Schema = "dbo")]
-    public class Envelope : IHasAddedWhen, IHasChangedWhen
+    public class Envelope : IHasAddedWhen, IHasChangedWhen, IEnvelope
     {
         public Envelope()
         {
@@ -106,7 +107,8 @@ namespace EnvelopeGenerator.Domain.Entities
 
         [JsonIgnore]
         [NotMapped]
-        public bool ReadOnly => EnvelopeTypeId == 2;
+        [Obsolete("Use EnvelopeGenerator.Domain.Interfaces.EnvelopeExtensions.IsReadAndConfirm extension method instead.")]
+        public bool ReadOnly => this.IsReadAndConfirm();
 
         [Column("CERTIFICATION_TYPE")]
         public int? CertificationType { get; set; }