diff --git a/.changeset/24126-system-overview-metric-height.md b/.changeset/24126-system-overview-metric-height.md
new file mode 100644
index 00000000000..e5c4a845abc
--- /dev/null
+++ b/.changeset/24126-system-overview-metric-height.md
@@ -0,0 +1,14 @@
+---
+'@objectstack/platform-objects': patch
+---
+
+Clause-②: no
+
+fix(platform-objects): the System Overview dashboard's six metric tiles declare `layout.h: 1`, one row tall, where they declared `2`
+
+The `system_overview` dashboard the Setup app ships (`SystemOverviewDashboard`) authored every one of its six `type: 'metric'` tiles (Total Users, Organizations, Active Sessions, Packages Installed, Login Events, Config Changes) at `layout.h: 2`. The console draws a widget over the grid rows its `h` names, each row floors at 5rem and grows to its content, and a metric card fills its box, so each tile drew a box about twice the height of its content: the title and the number in the top half, the lower half empty. The platform draws what the metadata declares, so the authored size is what is corrected.
+
+- **FROM:** the six metric tiles declare `layout: { …, h: 2 }`.
+- **TO:** the six metric tiles declare `layout: { …, h: 1 }`; each now draws at content height.
+- **Unchanged:** every `x`, `y` and `w`, the chart and table widgets (`h: 4`), every widget id, filter and binding, and every export.
+- **An org that already published an overlay of `system_overview`** is served that overlay as stored (ADR-0126 Regime O), so it keeps the tile heights it was saved with.
diff --git a/packages/platform-objects/src/apps/dashboards/system-overview-tile-layout.test.ts b/packages/platform-objects/src/apps/dashboards/system-overview-tile-layout.test.ts
new file mode 100644
index 00000000000..370dfcd5ebf
--- /dev/null
+++ b/packages/platform-objects/src/apps/dashboards/system-overview-tile-layout.test.ts
@@ -0,0 +1,72 @@
+// Copyright (c) 2026 ObjectStack. Licensed under the Apache-2.0 license.
+//
+// System Overview metric tile height (the maintainer's ruling B on
+// objectstack-ai/objectui#12704).
+//
+// The console draws a dashboard's positioned grid with `gridRow: span h` over
+// rows that floor at 5rem and grow to their content, and a metric card fills
+// its box. A KPI tile that declares `h: 2` therefore draws a box about twice the
+// height of its content: the title and the number sit in the top half and the
+// lower half is empty. The ruling is that the platform draws what the metadata
+// declares (ADR-0078 forbids an `h` that is read and not honoured), so the
+// AUTHORED size is what gets corrected, not the renderer: every metric tile on
+// the shipped board is ONE row tall.
+//
+// What is pinned is the property "a KPI tile is one row", read off `type`
+// rather than off a list of ids, so a metric tile added to the board later is
+// held to it as well. Only `h` is pinned. `x`, `y` and `w` place the tile and
+// are a separate decision this file has no opinion on.
+//
+// The pin carries its OPPOSITE DIRECTION, because "every metric tile is one row"
+// has two ways to pass vacuously:
+//
+//   - it also holds if the read finds no metric tile at all (a renamed key, a
+//     board that moved elsewhere) ⇒ the six tiles are named and the read must
+//     return exactly them;
+//   - it also holds if the fix were a blanket flattening of the whole board ⇒
+//     the chart and table widgets must stay taller than a tile, because they
+//     are the widgets that genuinely need the rows.
+
+import { describe, it, expect } from 'vitest';
+import { SystemOverviewDashboard } from './system_overview.dashboard.js';
+
+interface Widget {
+  id?: string;
+  type?: string;
+  layout?: { x: number; y: number; w: number; h: number };
+}
+const widgets: Widget[] = (SystemOverviewDashboard as unknown as { widgets?: Widget[] }).widgets ?? [];
+
+const metricTiles = widgets.filter((w) => w.type === 'metric');
+const otherWidgets = widgets.filter((w) => w.type !== 'metric');
+
+describe('System Overview metric tiles are one row tall', () => {
+  // Control for the assertion below: if this read ever returns nothing, the
+  // `h` check is a loop over an empty array and passes whatever the board says.
+  it('the read finds the six KPI tiles', () => {
+    expect(metricTiles.map((w) => w.id)).toEqual([
+      'widget_total_users',
+      'widget_organizations',
+      'widget_active_sessions',
+      'widget_packages_installed',
+      'widget_login_events',
+      'widget_config_changes',
+    ]);
+  });
+
+  it('every metric tile declares layout.h of 1', () => {
+    const offenders = metricTiles
+      .filter((w) => w.layout?.h !== 1)
+      .map((w) => `${w.id} → layout.h=${String(w.layout?.h)}`);
+    expect(offenders, 'metric tiles taller than one row').toEqual([]);
+  });
+
+  // Opposite direction: the correction is for the KPI tiles, not the board.
+  it('opposite direction: the chart and table widgets stay taller than a tile', () => {
+    expect(otherWidgets.length, 'the board still carries non-metric widgets').toBeGreaterThan(0);
+    const flattened = otherWidgets
+      .filter((w) => !(typeof w.layout?.h === 'number' && w.layout.h > 1))
+      .map((w) => `${w.id} → layout.h=${String(w.layout?.h)}`);
+    expect(flattened, 'non-metric widgets that lost their height').toEqual([]);
+  });
+});
diff --git a/packages/platform-objects/src/apps/dashboards/system_overview.dashboard.ts b/packages/platform-objects/src/apps/dashboards/system_overview.dashboard.ts
index 3444605e8a6..53aa021f461 100644
--- a/packages/platform-objects/src/apps/dashboards/system_overview.dashboard.ts
+++ b/packages/platform-objects/src/apps/dashboards/system_overview.dashboard.ts
@@ -42,7 +42,7 @@ export const SystemOverviewDashboard = Dashboard.create({
       dataset: 'sys_user_metrics', values: ['user_count'],
       title: 'Total Users',
       type: 'metric',
-      layout: { x: 0, y: 0, w: 3, h: 2 },
+      layout: { x: 0, y: 0, w: 3, h: 1 },
       // #7531 — a TOTAL must not move when the date bar moves. The dashboard's
       // `created_at` global filter is broadcast into every widget's analytics
       // query (#2501), so before this opt-out the tile reported "users created
@@ -67,7 +67,7 @@ export const SystemOverviewDashboard = Dashboard.create({
       // `requiresService: 'org-scoping'` — gate this KPI the same way so the
       // overview doesn't dangle a metric the admin can't act on.
       requiresService: 'org-scoping',
-      layout: { x: 3, y: 0, w: 3, h: 2 },
+      layout: { x: 3, y: 0, w: 3, h: 1 },
       // #7613 — the same #2501 fan-out as Total Users above, on the same row.
       // `sys_organization.created_at` exists, so the date bar landed on it and
       // the tile reported "organizations created in the last 7 days" under a
@@ -83,7 +83,7 @@ export const SystemOverviewDashboard = Dashboard.create({
       dataset: 'sys_session_metrics', values: ['session_count'],
       title: 'Active Sessions',
       type: 'metric',
-      layout: { x: 6, y: 0, w: 3, h: 2 },
+      layout: { x: 6, y: 0, w: 3, h: 1 },
       // #7531 — "Active Sessions" counted EVERY `sys_session` row: the dataset
       // is a bare count and the widget carried no predicate, so a signed-out or
       // long-expired session was still reported as active. `sys_session` can
@@ -113,7 +113,7 @@ export const SystemOverviewDashboard = Dashboard.create({
       // Cloud-only object — only registered when service-tenant is loaded.
       // Hide this widget gracefully in single-environment runtimes.
       requiresObject: 'sys_package_installation',
-      layout: { x: 9, y: 0, w: 3, h: 2 },
+      layout: { x: 9, y: 0, w: 3, h: 1 },
       // Which installations count: the ones that are actually installed. This
       // predicate is the tile's own, and it is ORTHOGONAL to the opt-out below
       // — the two answer different questions and both stand.
@@ -162,7 +162,7 @@ export const SystemOverviewDashboard = Dashboard.create({
       dataset: 'sys_audit_log_metrics', values: ['event_count'],
       title: 'Login Events',
       type: 'metric',
-      layout: { x: 0, y: 2, w: 6, h: 2 },
+      layout: { x: 0, y: 2, w: 6, h: 1 },
       filter: { action: 'login' },
       colorVariant: 'blue',
       description: 'Authentication events recorded by the audit log',
@@ -172,7 +172,7 @@ export const SystemOverviewDashboard = Dashboard.create({
       dataset: 'sys_audit_log_metrics', values: ['event_count'],
       title: 'Config Changes',
       type: 'metric',
-      layout: { x: 6, y: 2, w: 6, h: 2 },
+      layout: { x: 6, y: 2, w: 6, h: 1 },
       filter: { action: 'config_change' },
       colorVariant: 'blue',
       description: 'System configuration modifications',