diff --git a/biopet.wdl b/biopet.wdl
index cdfdff747a43c37f6cfe5aba647a8f3bb2f450c7..7271f63fae0337eed9a3aeb96d355aac8ae3f0d1 100644
--- a/biopet.wdl
+++ b/biopet.wdl
@@ -82,7 +82,7 @@ task SampleConfig {
     }
 
     runtime {
-        memory: select_first([memory, 3.0]) * select_first([memoryMultiplier, 1.5])
+        memory: ceil(select_first([memory, 3.0]) * select_first([memoryMultiplier, 1.5]))
     }
 }
 
@@ -146,6 +146,6 @@ task BaseCounter {
     }
 
     runtime {
-        memory: select_first([memory, 12.0]) * select_first([memoryMultiplier, 1.5])
+        memory: ceil(select_first([memory, 12.0]) * select_first([memoryMultiplier, 1.5]))
     }
 }
diff --git a/fastqc.wdl b/fastqc.wdl
index aa9073e93043dbd27aaae8ca595d695eac7ee14e..d7850ac481b62d8e9d02e789553c94e4e50291d5 100644
--- a/fastqc.wdl
+++ b/fastqc.wdl
@@ -89,7 +89,7 @@ task extractAdapters {
     }
 
     runtime {
-        memory: select_first([memory, 4.0]) * select_first([memoryMultiplier, 1.5])
+        memory: ceil(select_first([memory, 4.0]) * select_first([memoryMultiplier, 1.5]))
     }
 }