07-18-2011, 11:50 AM
There is another problem with trying to bore tunnels through that concrete wall that you may not realize. I don't know when your house was built or what the codes are in Norway. Here in Long Beach the contractor that did the remodeling on my house built a preschool building in downtown Long Beach. It was done with concrete walls that were poured in place after the rebar was positioned, and door frames and window frames were installed to keep the concrete out of the door and window openings. I stopped by to look at the building and he showed me pictures of the rebar structure before the concrete was poured. With our earthquake standards it looked like a spider web made of steel! He also had to measure precisely where plumbing and electrical would go through the walls so that after the forms were removed he could bore holes for the plumbing & wiring avoiding hitting any rebar, and save the resulting core samples for strength testing! Of course all of the rebar was required because of the strict earth quake standards in place here in Southern California.