diff --git a/datatypes/magicplan/domain/mapper.py b/datatypes/magicplan/domain/mapper.py
index 1804e58e..1342cc8b 100644
--- a/datatypes/magicplan/domain/mapper.py
+++ b/datatypes/magicplan/domain/mapper.py
@@ -2,7 +2,15 @@ from typing import Optional
 
 import datatypes.magicplan.api.response as api
 from datatypes.magicplan.api.response import MagicPlanPlan
-from datatypes.magicplan.domain.models import Plan, Floor, Room, Window, Door
+from datatypes.magicplan.domain.models import (
+    Door,
+    DoorVentilation,
+    Floor,
+    Plan,
+    Room,
+    Window,
+    WindowVentilation,
+)
 
 
 def map_plan(mp: MagicPlanPlan) -> Plan:
@@ -60,6 +68,36 @@ def _map_window(wi: api.WallItem) -> Window:
         height_m=round(wi.size.z, 2),
         area_m2=round(wi.size.x * wi.size.z, 2),
         opening_type=wi.symbol.id.removeprefix("window"),
+        ventilation=_map_window_ventilation(wi.custom_displayable_fields),
+    )
+
+
+def _map_window_ventilation(
+    fields: list[api.SurveyField],
+) -> Optional[WindowVentilation]:
+    if not fields:
+        return None
+    by_label = {f.label: f for f in fields}
+
+    def _str(label: str) -> Optional[str]:
+        f = by_label.get(label)
+        if f is None or not f.value.has_value:
+            return None
+        v = f.value.value
+        return v[0] if isinstance(v, list) else v
+
+    def _int(label: str) -> Optional[int]:
+        raw = _str(label)
+        return int(raw) if raw is not None else None
+
+    return WindowVentilation(
+        opening_type=_str("Opening Type"),
+        num_openings=_int("Number of Openings (In Same Window)"),
+        pct_openable=_int("% of Window Openable"),
+        trickle_vent_area_mm2=_int(
+            "Trickle Vent Effective Area (mm2) (No Code Then Width x Height)"
+        ),
+        num_trickle_vents=_int("No. of Trickle Vents"),
     )