diff --git a/dumux/common/math.hh b/dumux/common/math.hh
index e076ffac7386ab89250a2f1c4e59ea7fdc0efe1f..c1fb3db5a3be9df5c5f4270f4e0e13ea16514255 100644
--- a/dumux/common/math.hh
+++ b/dumux/common/math.hh
@@ -501,7 +501,7 @@ Scalar antoine(Scalar temperature,
  * Returns 0 if the argument is zero.
  */
 template<class ValueType>
-int sign(const ValueType& value)
+constexpr int sign(const ValueType& value) noexcept
 {
     return (ValueType(0) < value) - (value < ValueType(0));
 }