diff --git a/lib/general.sh b/lib/general.sh
index 4a19d9541e..6207f41807 100644
--- a/lib/general.sh
+++ b/lib/general.sh
@@ -547,6 +547,12 @@ prepare_host()
 
 	# create directory structure
 	mkdir -p $DEST/debs/extra $DEST/{config,debug,patch} $SRC/userpatches/overlay $SRC/cache/{sources,toolchains,rootfs} $SRC/.tmp
+	if [[ -n $SUDO_USER ]]; then
+		chgrp --quiet sudo cache output userpatches
+		# SGID bit on cache/sources breaks kernel dpkg packaging
+		chmod --quiet g+w,g+s output userpatches
+	fi
+	
 	find $SRC/patch -type d ! -name . | sed "s%/patch%/userpatches%" | xargs mkdir -p
 
 	# download external Linaro compiler and missing special dependencies since they are needed for certain sources
diff --git a/lib/main.sh b/lib/main.sh
index 4f89007957..8df333ae32 100644
--- a/lib/main.sh
+++ b/lib/main.sh
@@ -17,6 +17,10 @@ if [[ $(basename $0) == main.sh ]]; then
 	exit -1
 fi
 
+# default umask for root is 022 so parent directories won't be group writeable without this
+# this is used instead of making the chmod in prepare_host() recursive
+umask 002
+
 # destination
 DEST=$SRC/output