diff --git a/homeassistant/components/sensor/envirophat.py b/homeassistant/components/sensor/envirophat.py
index 0c4bb42cf8f..48370d76c83 100644
--- a/homeassistant/components/sensor/envirophat.py
+++ b/homeassistant/components/sensor/envirophat.py
@@ -15,7 +15,8 @@ import homeassistant.helpers.config_validation as cv
 from homeassistant.helpers.entity import Entity
 from homeassistant.util import Throttle
 
-REQUIREMENTS = ['envirophat==0.0.6']
+REQUIREMENTS = ['envirophat==0.0.6',
+                'smbus-cffi==0.5.1']
 
 _LOGGER = logging.getLogger(__name__)
 
diff --git a/requirements_all.txt b/requirements_all.txt
index 4f0edd805e1..3dd416f3b67 100644
--- a/requirements_all.txt
+++ b/requirements_all.txt
@@ -764,6 +764,9 @@ sleekxmpp==1.3.2
 # homeassistant.components.sleepiq
 sleepyq==0.6
 
+# homeassistant.components.sensor.envirophat
+smbus-cffi==0.5.1
+
 # homeassistant.components.media_player.snapcast
 snapcast==1.2.2