diff --git a/dbt/models/default/default.vw_card_res_char.sql b/dbt/models/default/default.vw_card_res_char.sql
index d5b5d83fa..58f80b5d0 100644
--- a/dbt/models/default/default.vw_card_res_char.sql
+++ b/dbt/models/default/default.vw_card_res_char.sql
@@ -12,6 +12,58 @@ WITH multicodes AS (
     GROUP BY parid, taxyr
 ),
 
+-- Gather HIE start and end years from both ADDN and OBY tables. We need to
+-- stack them to properly count the number of active and expiring HIEs for each
+-- PIN-year combination below. We define unique start and end dates within cards
+-- as separate HIEs.
+all_hies AS (
+    SELECT DISTINCT
+        parid AS pin,
+        card,
+        taxyr AS year,
+        CAST(taxyr AS INT) AS year_int,
+        userval1 AS hie_start,
+        userval2 AS hie_end
+    FROM {{ source('iasworld', 'addn') }}
+    WHERE lline > 0
+        AND cur = 'Y'
+        AND deactivat IS NULL
+        AND userval1 IS NOT NULL
+        AND userval2 IS NOT NULL
+    UNION ALL
+    SELECT DISTINCT
+        parid AS pin,
+        card,
+        taxyr AS year,
+        CAST(taxyr AS INT) AS year_int,
+        CAST(user10 AS INT) AS hie_start,
+        CAST(user14 AS INT) AS hie_end
+    FROM {{ source('iasworld', 'oby') }}
+    WHERE cur = 'Y'
+        AND deactivat IS NULL
+        AND user10 IS NOT NULL
+        AND user14 IS NOT NULL
+        AND class = '288'
+),
+
+hies AS (
+    SELECT
+        pin,
+        year,
+        SUM(
+            CAST(
+                -- HIE adjustments to AVs in iasworld.asmt include the start and
+                -- end years, so we use a between statement here.
+                year_int BETWEEN hie_start AND hie_end AS INT
+            )
+        ) AS hie_num_active,
+        SUM(CAST(year_int = hie_end AS INT)) AS hie_num_expiring
+    FROM all_hies
+    GROUP BY
+        pin,
+        year
+),
+
 -- Conditionals in CTE do not ensure distinct outputs
 pools AS (
     SELECT
@@ -129,7 +181,11 @@ SELECT
     -- This is a brand new characteristic being collected by Valuations and we
     -- are not yet confident about its completeness or accuracy.
     -- This is not currently being used in open data or modeling.
-    COALESCE(pools.in_ground_pool, FALSE) AS char_in_ground_pool
+    COALESCE(pools.in_ground_pool, FALSE) AS char_in_ground_pool,
+
+    -- HIE data
+    COALESCE(hies.hie_num_active, 0) AS hie_num_active,
+    COALESCE(hies.hie_num_expiring, 0) AS hie_num_expiring
 
 FROM {{ source('iasworld', 'pardat') }} AS par
 INNER JOIN {{ source('iasworld', 'dweldat') }} AS dwel
@@ -151,6 +207,9 @@ LEFT JOIN {{ source('iasworld', 'legdat') }} AS leg
 LEFT JOIN pools
     ON dwel.parid = pools.parid
     AND dwel.taxyr = pools.taxyr
+LEFT JOIN hies
+    ON dwel.parid = hies.pin
+    AND dwel.taxyr = hies.year
 WHERE par.cur = 'Y'
     AND par.deactivat IS NULL
     AND par.class NOT IN ('999')
diff --git a/dbt/models/default/schema/default.vw_card_res_char.yml b/dbt/models/default/schema/default.vw_card_res_char.yml
index f92eb41f5..ed2f47343 100644
--- a/dbt/models/default/schema/default.vw_card_res_char.yml
+++ b/dbt/models/default/schema/default.vw_card_res_char.yml
@@ -84,6 +84,10 @@ models:
         description: '{{ doc("shared_column_char_yrblt") }}'
       - name: class
         description: '{{ doc("shared_column_class") }}'
+      - name: hie_num_active
+        description: '{{ doc("shared_column_hie_num_active") }}'
+      - name: hie_num_expiring
+        description: '{{ doc("shared_column_hie_num_expiring") }}'
       - name: pin
         description: '{{ doc("shared_column_pin") }}'
       - name: pin10
diff --git a/dbt/models/iasworld/columns.md b/dbt/models/iasworld/columns.md
index e860bab8f..5ea67300c 100644
--- a/dbt/models/iasworld/columns.md
+++ b/dbt/models/iasworld/columns.md
@@ -431,6 +431,18 @@ Group adjustment value
 Homesite indicator
 {% enddocs %}
 
+## hie_end
+
+{% docs column_hie_end %}
+Home improvement exemption end year
+{% enddocs %}
+
+## hie_start
+
+{% docs column_hie_start %}
+Home improvement exemption start year
+{% enddocs %}
+
 ## iasw_id
 
 {% docs column_iasw_id %}
diff --git a/dbt/models/iasworld/docs.md b/dbt/models/iasworld/docs.md
index 57bba23df..d2aa53b90 100644
--- a/dbt/models/iasworld/docs.md
+++ b/dbt/models/iasworld/docs.md
@@ -12,6 +12,14 @@ Control table for `asmt` admin module - multi-jurisdiction version.
 Residential additions. Stores data about Home Improvement Exemptions (HIEs)
 and other information about `iasworld.dweldat` properties.
 
+### Nuance
+
+- In order to isolate HIEs, condition on `lline > 0`
+- HIEs from `addn` can be joined to dweldat by card
+- The characteristic changes in `addn` are applied immediately to the
+corresponding `dweldat` characteristics rather then when HIEs "roll off".
+- Individual HIEs are defined within start/end year and card
+
 **Primary Key**: `jur`, `taxyr`, `parid`, `card`, `lline`
 {% enddocs %}
 
@@ -298,6 +306,15 @@ Taxpayer information such as name and mailing address.
 Outbuilding table. This is the main storage table for condo unit-level data.
 It also stores other miscellaneous sub-PIN information like HIEs.
 
+### Nuance
+
+- In order to isolate HIEs, condition on `class = '288'`
+- HIEs from `oby` cannot necessarily be joined to `dweldat` by card, though that
+is the intended behavior
+- The characteristic changes in `oby` are applied immediately to the
+corresponding `dweldat` characteristics rather then when HIEs "roll off".
+- Individual HIEs are defined within start/end year and card
+
 **Primary Key**: `jur`, `taxyr`, `parid`, `card`, `lline`
 {% enddocs %}
 
diff --git a/dbt/models/iasworld/schema/iasworld.addn.yml b/dbt/models/iasworld/schema/iasworld.addn.yml
index fe7e60677..bb76e8d02 100644
--- a/dbt/models/iasworld/schema/iasworld.addn.yml
+++ b/dbt/models/iasworld/schema/iasworld.addn.yml
@@ -265,6 +265,10 @@ sources:
             description: '{{ doc("column_trans_id") }}'
           - name: upd_status
             description: '{{ doc("column_upd_status") }}'
+          - name: userval1
+            description: '{{ doc("column_hie_start") }}'
+          - name: userval2
+            description: '{{ doc("column_hie_end") }}'
           - name: value
             description: Value of the addition
           - name: vect
diff --git a/dbt/models/iasworld/schema/iasworld.oby.yml b/dbt/models/iasworld/schema/iasworld.oby.yml
index 277322bd7..45e3d054d 100644
--- a/dbt/models/iasworld/schema/iasworld.oby.yml
+++ b/dbt/models/iasworld/schema/iasworld.oby.yml
@@ -448,6 +448,10 @@ sources:
             description: Number of identical units
           - name: upd_status
             description: '{{ doc("column_upd_status") }}'
+          - name: user10
+            description: '{{ doc("column_hie_start") }}'
+          - name: user14
+            description: '{{ doc("column_hie_end") }}'
           - name: user16
             description: '{{ doc("shared_column_alternative_cdu") }}'
           - name: valmeth
diff --git a/dbt/models/model/model.vw_card_res_input.sql b/dbt/models/model/model.vw_card_res_input.sql
index 6f33c9ada..352b3d937 100644
--- a/dbt/models/model/model.vw_card_res_input.sql
+++ b/dbt/models/model/model.vw_card_res_input.sql
@@ -114,6 +114,8 @@ forward_fill AS (
         ch.char_ncu,
         ch.char_tp_plan,
         ch.char_recent_renovation,
+        ch.hie_num_active,
+        ch.hie_num_expiring,
 
         -- Land and lot size indicators
         sp.char_land_sf_95_percentile,
@@ -216,6 +218,8 @@ SELECT
     f1.char_ncu,
     f1.char_tp_plan,
     f1.char_recent_renovation,
+    f1.hie_num_active,
+    f1.hie_num_expiring,
     f1.char_land_sf_95_percentile,
     f1.ind_land_gte_95_percentile,
     f1.char_bldg_sf_95_percentile,
diff --git a/dbt/models/model/schema.yml b/dbt/models/model/schema.yml
index 0d95d66b7..10ad2da17 100644
--- a/dbt/models/model/schema.yml
+++ b/dbt/models/model/schema.yml
@@ -955,6 +955,10 @@ models:
         description: '{{ doc("shared_column_char_use") }}'
       - name: char_yrblt
         description: '{{ doc("shared_column_char_yrblt") }}'
+      - name: hie_num_active
+        description: '{{ doc("shared_column_hie_num_active") }}'
+      - name: hie_num_expiring
+        description: '{{ doc("shared_column_hie_num_expiring") }}'
       - name: ind_bldg_gte_95_percentile
         description: |
           Indicator for a PIN with building square footage larger
diff --git a/dbt/models/shared_columns.md b/dbt/models/shared_columns.md
index 54031bcd0..a8e957c95 100644
--- a/dbt/models/shared_columns.md
+++ b/dbt/models/shared_columns.md
@@ -1113,6 +1113,18 @@ Possible values for this variable are:
 Year the property was constructed
 {% enddocs %}
 
+## hie_num_active
+
+{% docs shared_column_hie_num_active %}
+Number of active home improvement exemptions
+{% enddocs %}
+
+## hie_num_expiring
+
+{% docs shared_column_hie_num_expiring %}
+Number of home improvement exemptions that will expire after the current year
+{% enddocs %}
+
 # Cook County
 
 ## card