"I walk from my house."
Translation:Ich gehe zu Fuß von meinem Haus.
I looked into it because i remembered having been corrected by native speaker from "Haus" to "Hause". It looks like exactly what kyky says, but that in some commonly used expressions the old Dative sticked: "zu Hause" meant "at the house" but now means "at home" and didn't update its dative "nach Hause" "im Hause" are similar.
Please add more examples if you know them. My sources: http://forum.wordreference.com/showthread.php?t=1574076 http://www.gutefrage.net/frage/im-hause-oder-im-haus