diff --git a/pmb/config/__init__.py b/pmb/config/__init__.py
index 5f93ae50..1c498cf2 100644
--- a/pmb/config/__init__.py
+++ b/pmb/config/__init__.py
@@ -58,7 +58,8 @@ config_keys = ["aports",
                "ui_extras",
                "user",
                "work",
-               "boot_size"]
+               "boot_size",
+               "extra_space"]
 
 # Config file/commandline default values
 # $WORK gets replaced with the actual value for args.work (which may be
@@ -94,6 +95,7 @@ defaults = {
     "user": "user",
     "work": os.path.expanduser("~") + "/.local/var/pmbootstrap",
     "boot_size": "128",
+    "extra_space": "0"
 }
 
 #
diff --git a/pmb/config/init.py b/pmb/config/init.py
index 915bc3fe..094b4b5f 100644
--- a/pmb/config/init.py
+++ b/pmb/config/init.py
@@ -341,6 +341,7 @@ def ask_for_device(args):
 def ask_for_additional_options(args, cfg):
     # Allow to skip additional options
     logging.info("Additional options:"
+                 f" extra free space: {args.extra_space} MB,"
                  f" boot partition size: {args.boot_size} MB,"
                  f" parallel jobs: {args.jobs},"
                  f" ccache per arch: {args.ccache_size}")
@@ -349,6 +350,18 @@ def ask_for_additional_options(args, cfg):
                                    default=False):
         return
 
+    # Extra space
+    logging.info("Set extra free space to 0, unless you ran into a 'No space"
+                 " left on device' error. In that case, the size of the"
+                 " rootfs could not be calculated properly on your machine,"
+                 " and we need to add extra free space to make the image big"
+                 " enough to fit the rootfs (pmaports#1904)."
+                 " How much extra free space do you want to add to the image"
+                 " (in MB)?")
+    answer = pmb.helpers.cli.ask(args, "Extra space size", None,
+                                 args.extra_space, validation_regex="[0-9]+")
+    cfg["pmbootstrap"]["extra_space"] = answer
+
     # Boot size
     logging.info("What should be the boot partition size (in MB)?")
     answer = pmb.helpers.cli.ask(args, "Boot size", None, args.boot_size,
diff --git a/pmb/install/_install.py b/pmb/install/_install.py
index 42fa2468..d40c7e4c 100644
--- a/pmb/install/_install.py
+++ b/pmb/install/_install.py
@@ -51,7 +51,7 @@ def get_subpartitions_size(args, suffix):
     chroot = f"{args.work}/chroot_{suffix}"
     root = pmb.helpers.other.folder_size(args, chroot) / 1024 / 1024
     root *= 1.20
-    root += 50
+    root += 50 + int(args.extra_space)
     return (boot, root)
 
 
diff --git a/pmb/parse/arguments.py b/pmb/parse/arguments.py
index 4ad7bd8f..73406f61 100644
--- a/pmb/parse/arguments.py
+++ b/pmb/parse/arguments.py
@@ -357,6 +357,10 @@ def arguments():
                              pmb.config.defaults["mirror_alpine"],
                         metavar="URL")
     parser.add_argument("-j", "--jobs", help="parallel jobs when compiling")
+    parser.add_argument("-E", "--extra-space",
+                        help="specify an integer with the amount of additional"
+                             "space to allocate to the image in MB (default"
+                             " 0)")
     parser.add_argument("-B", "--boot-size",
                         help="specify an integer with your preferred boot"
                              "partition size on target machine in MB (default"
diff --git a/test/test_questions.py b/test/test_questions.py
index c98f2d54..02d66c23 100644
--- a/test/test_questions.py
+++ b/test/test_questions.py
@@ -261,9 +261,10 @@ def test_questions_additional_options(args, monkeypatch):
     assert cfg == {"pmbootstrap": {}}
 
     # Answer everything
-    fake_answers(monkeypatch, ["y", "64", "5", "2G", "n"])
+    fake_answers(monkeypatch, ["y", "128", "64", "5", "2G", "n"])
     func(args, cfg)
-    assert cfg == {"pmbootstrap": {"boot_size": "64",
+    assert cfg == {"pmbootstrap": {"extra_space": "128",
+                                   "boot_size": "64",
                                    "jobs": "5",
                                    "ccache_size": "2G"}}