diff --git a/addons/web/static/src/js/views/calendar/calendar_controller.js b/addons/web/static/src/js/views/calendar/calendar_controller.js
index edb8e54e0b7..37ee9f94fb7 100644
--- a/addons/web/static/src/js/views/calendar/calendar_controller.js
+++ b/addons/web/static/src/js/views/calendar/calendar_controller.js
@@ -51,6 +51,7 @@ var CalendarController = AbstractController.extend({
         this.quickAddPop = params.quickAddPop;
         this.disableQuickCreate = params.disableQuickCreate;
         this.eventOpenPopup = params.eventOpenPopup;
+        this.showUnusualDays = params.showUnusualDays;
         this.formViewId = params.formViewId;
         this.readonlyFormViewId = params.readonlyFormViewId;
         this.mapping = params.mapping;
@@ -154,6 +155,31 @@ var CalendarController = AbstractController.extend({
         this.model[to]();
         return this.reload();
     },
+    /**
+     * @override
+     * @private
+     */
+    _update: function () {
+        var self = this;
+        if (!this.showUnusualDays) {
+            return this._super.apply(this, arguments);
+        }
+        return this._super.apply(this, arguments).then(function () {
+            self._rpc({
+                model: self.modelName,
+                method: 'get_unusual_days',
+                args: [self.model.data.start_date.format('YYYY-MM-DD'), self.model.data.end_date.format('YYYY-MM-DD')],
+                context: self.context,
+            }).then(function (data) {
+                _.each(self.$el.find('td.fc-day'), function (td) {
+                    var $td = $(td);
+                    if (data[$td.data('date')]) {
+                        $td.addClass('o_calendar_disabled');
+                    }
+                });
+            });
+        });
+    },
     /**
      * @private
      * @param {Object} record
diff --git a/addons/web/static/src/js/views/calendar/calendar_view.js b/addons/web/static/src/js/views/calendar/calendar_view.js
index 1b081316f20..b1a6ea7be13 100644
--- a/addons/web/static/src/js/views/calendar/calendar_view.js
+++ b/addons/web/static/src/js/views/calendar/calendar_view.js
@@ -131,6 +131,7 @@ var CalendarView = AbstractView.extend({
         }
 
         this.controllerParams.eventOpenPopup = utils.toBoolElse(attrs.event_open_popup || '', false);
+        this.controllerParams.showUnusualDays = utils.toBoolElse(attrs.show_unusual_days || '', false);
         this.controllerParams.mapping = mapping;
         this.controllerParams.context = params.context || {};
         this.controllerParams.displayName = params.action && params.action.name;
diff --git a/addons/web/static/src/scss/web_calendar.scss b/addons/web/static/src/scss/web_calendar.scss
index ed99c4fcd6f..759dfa94ad0 100644
--- a/addons/web/static/src/scss/web_calendar.scss
+++ b/addons/web/static/src/scss/web_calendar.scss
@@ -98,6 +98,10 @@ $o-cw-filter-avatar-size: 20px;
             color: white;
         }
 
+        .o_calendar_disabled {
+            background-color: $gray-200;
+            border-color: white !important;
+        }
 
         // ======  Specific agenda types ======
         // ====================================
diff --git a/odoo/addons/base/rng/calendar_view.rng b/odoo/addons/base/rng/calendar_view.rng
index a6737fbcfa2..f073bab4bf1 100644
--- a/odoo/addons/base/rng/calendar_view.rng
+++ b/odoo/addons/base/rng/calendar_view.rng
@@ -18,6 +18,7 @@
             <rng:optional><rng:attribute name="quick_add" /></rng:optional>
             <rng:optional><rng:attribute name="color" /></rng:optional>
             <rng:optional><rng:attribute name="event_open_popup" /></rng:optional>
+            <rng:optional><rng:attribute name="show_unusual_days" /></rng:optional>
             <rng:optional><rng:attribute name="js_class"/></rng:optional>
             <rng:optional><rng:attribute name="hide_time"/></rng:optional>
             <rng:optional><rng:attribute name="hide_date"/></rng:optional>