It's possible that the rendering is showing what was expected of the back patio, as none of the homes have this elevation. We can tell it is a patio because there is a chaise lounge on it, there is no driveway, and the concrete is a bit fancier than you might do in a carport. It would be highly unsual at this time to advertise the back of the home rather than the front elevation as a selling point. It's possible that Haver was thinking of the patio-port concept at this time, which he would later execute in his Town and County Homes of 1955. They do feature scored concrete.