diff --git a/control/zone.hpp b/control/zone.hpp
index 20b9ac9..cc05959 100644
--- a/control/zone.hpp
+++ b/control/zone.hpp
@@ -178,6 +178,14 @@
             return _incSpeedDelta;
         };
 
+        /**
+         * @brief Calculate the requested target speed from the given delta
+         * and increase the fan speeds, not going above the ceiling.
+         *
+         * @param[in] targetDelta - The delta to increase the target speed by
+         */
+        void requestSpeedIncrease(uint64_t targetDelta);
+
     private:
 
         /**
@@ -226,6 +234,11 @@
         bool _isActive = true;
 
         /**
+         * Target speed for this zone
+         */
+        uint64_t _targetSpeed = _fullSpeed;
+
+        /**
          * Speed increase delta
          */
         uint64_t _incSpeedDelta = 0;