I've been researching direct exchange systems and have been measuring the temperatures of my concrete basement walls and floors. The floors are 6-8 feet below grade and they average 60 degrees. I'm in Seattle Washington. Even when it was the low for the year I was over 55 degrees. So the question is if I use copper tubing and make sure it is grouted or some other way thermally placed against the walls or floors and grouted to it, can I use this as my loop? I have over 150 lineal feet of concrete wall 8 feet tall and an additional 1000 square feet of concrete floor. Seems like as long as I fir these out to protect the pipe it should work? Anyone ever heard of that or have any idea?