Earth tube for make-up air
I am planing on building a very tight house. Before I ever heard of “earth tubes” I was planing on providing make-up air. About 90 feet from the home I am going to build an out building. On this outbuilding on an exterior wall i was going to build a box that would hold a furnace filter from which I was planning on using 6″ s&d pipe to run down 8′ into the ground & then over to the house from where it would come up into a chimney chase & ultimately exit at the top of the conditioned attic space. My thoughts: in winter the cold-make-up air would be tempered by going underground & dumping into the bottom of the chimney chase where it would get heated before exiting into the attic. In summer the hot-outside air could be cooled by passing underground & then dumping into the hottest part of the house at the highest point. An added benefit was being able to have filtered make-up air that would be easy to service @ the shed & would not be unsightly on the side of the house. All good right?
…so now I have become aware that condensation can happen in that pipe while underground…something i had not thought of. I live in the central mountains of Idaho at 5,000 feet. Lots of snow in the winter, wet springs & fall but quite dry in the summer. Is there any way of knowing before hand if condensation will be an issue? I can’t have “drain holes” in the pipe because radon is an issue in the area so the pipe needs to be sealed.
Should I just scrap the whole idea & install an ugly filter & air-make-up intake on the side of the house? Martin, I would really appreciate your thoughts on this one…wish i could see the future of any condensation issues in the pipe, because I think it sounds like a great idea. -eric