diff --git a/definitions/tools/vep.wdl b/definitions/tools/vep.wdl
index 28a37740..c5612b33 100644
--- a/definitions/tools/vep.wdl
+++ b/definitions/tools/vep.wdl
@@ -26,10 +26,10 @@ task vepTask {
     File? synonyms_file
   }
 
-  Float cache_size = 2*size(cache_dir_zip, "GB")  # doubled to unzip
-  Float vcf_size = 2*size(vcf, "GB")  # doubled for output vcf
+  Float cache_size = 3*size(cache_dir_zip, "GB")  # tripled to unzip
+  Float vcf_size = 3*size(vcf, "GB")  # tripled for output vcf
   Float reference_size = size([reference, reference_fai, reference_dict], "GB")
-  Int space_needed_gb = 10 + round(reference_size + vcf_size + cache_size + size(synonyms_file, "GB"))
+  Int space_needed_gb = 20 + round(reference_size + vcf_size + cache_size + size(synonyms_file, "GB"))
   runtime {
     preemptible: 1
     maxRetries: 2