diff --git a/src/libcalamares/utils/CalamaresUtils.cpp b/src/libcalamares/utils/CalamaresUtils.cpp
index 9e678737b..c0175f771 100644
--- a/src/libcalamares/utils/CalamaresUtils.cpp
+++ b/src/libcalamares/utils/CalamaresUtils.cpp
@@ -366,6 +366,22 @@ getInteger( const QVariantMap& map, const QString& key, int d )
     return result;
 }
 
+double
+getDouble( const QVariantMap& map, const QString& key, double d )
+{
+    double result = d;
+    if ( map.contains( key ) )
+    {
+        auto v = map.value( key );
+        if ( v.type() == QVariant::Int )
+            result = v.toInt();
+        else if ( v.type() == QVariant::Double )
+            result = v.toDouble();
+    }
+
+    return result;
+}
+
 QVariantMap
 getSubMap( const QVariantMap& map, const QString& key, bool& success )
 {
diff --git a/src/libcalamares/utils/CalamaresUtils.h b/src/libcalamares/utils/CalamaresUtils.h
index 9b279ef43..13caf1cad 100644
--- a/src/libcalamares/utils/CalamaresUtils.h
+++ b/src/libcalamares/utils/CalamaresUtils.h
@@ -110,10 +110,15 @@ namespace CalamaresUtils
     DLLEXPORT QString getString( const QVariantMap& map, const QString& key );
 
     /**
-     * Get an integer value from a mapping; returns @p default if no value.
+     * Get an integer value from a mapping; returns @p d if no value.
      */
     DLLEXPORT int getInteger( const QVariantMap& map, const QString& key, int d );
 
+    /**
+     * Get a double value from a mapping (integers are converted); returns @p d if no value.
+     */
+    DLLEXPORT double getDouble( const QVariantMap& map, const QString& key, double d );
+
     /**
      * Returns a sub-map (i.e. a nested map) from the given mapping with the
      * given key. @p success is set to true if the @p key exists