I doubt he'll mind you being stoned in the house, he just doesn't want the cops coming round to find a oz of weed in HIS house .
My parents know I smoke, but I think I remember them saying don't bring it into the house, I agreed with it. (I still do bring it into the house without their knowledge though). My mum also advises me to keep it to weed only. So far so good. :thumbsup:
Your parents shouldn't notice you being stoned anyhow if you try to act normal. If you can't, just come in and goto your room or something. But I can't say what to do because I don't know what your lifestyle is, just my thoughts......