diff --git a/packages/document-issue/src/document_issue/document.py b/packages/document-issue/src/document_issue/document.py
index 651b8589..320b20f7 100644
--- a/packages/document-issue/src/document_issue/document.py
+++ b/packages/document-issue/src/document_issue/document.py
@@ -4,11 +4,11 @@
 from typing import Annotated
 
 from annotated_types import Len
-from pydantic import AliasChoices, Field, WithJsonSchema, field_validator
+from pydantic import AliasChoices, Field, WithJsonSchema, field_validator, model_validator
 from typing_extensions import Literal
 
 from document_issue.basemodel import BaseModel
-from document_issue.enums import DocSource, PaperSizeEnum, ScalesEnum
+from document_issue.enums import DocSource, DocumentTypeEnum, PaperSizeEnum, ScalesEnum
 
 
 class FormatConfiguration(BaseModel):
@@ -67,10 +67,17 @@ class DocumentBase(BaseModel):
         examples=DocSource._member_names_,
         alias="doc_source",
     )
+    document_type: DocumentTypeEnum = Field(
+        DocumentTypeEnum.es,
+        description="type of document",
+        alias="doc_type",
+        title="Document Type",
+    )
     paper_size: str | PaperSizeEnum = Field(
         "A4",
         description="paper size of the document",
         alias="size",
+        json_schema_extra={"disabled": True},
     )
     scale: str | ScalesEnum = Field(
         "nts",
@@ -111,6 +118,18 @@ def validate_name_nomenclature(cls, v: str)-> str:
         li_nomenclature = [s.strip() for s in li_nomenclature]
         return "-".join(li_nomenclature)
 
+    @model_validator(mode="after")
+    def set_paper_size_based_on_document_type(self) -> DocumentBase:
+        """Set the paper size based on the document type."""
+        if self.document_type == DocumentTypeEnum.es:
+            self.paper_size = PaperSizeEnum.A4
+        elif self.document_type == DocumentTypeEnum.prs:
+            self.paper_size = PaperSizeEnum.A3
+        elif self.document_type == DocumentTypeEnum.rds:
+            self.paper_size = PaperSizeEnum.A4
+        else:
+            self.paper_size = PaperSizeEnum.na
+        return self
 
 class Document(DocumentBase):
     """Document model."""
diff --git a/packages/document-issue/src/document_issue/enums.py b/packages/document-issue/src/document_issue/enums.py
index 77d78156..b74ffb3b 100644
--- a/packages/document-issue/src/document_issue/enums.py
+++ b/packages/document-issue/src/document_issue/enums.py
@@ -64,5 +64,10 @@ class IssueFormatEnum(Enum):
     p = "paper - full size"
     r = "paper - reduced size"
 
+class DocumentTypeEnum(str, Enum):
+    """maps DocumentType codes to string description."""
 
-
+    es: str = "Equipment Schedule"
+    rds: str = "Room Data Schedule"
+    prs: str = "Plantroom Schedule"
+    # nzc: str = "Net-Zero Carbon Schedule"  # TODO: Implement this in the future  # noqa: ERA001