"We ended up burying 100 ft of 12” pipe 6 foot deep to provide fresh air."

Wait, isn't this a radon concern? Pulling air from soil as the only means of fresh air?

My concern over this came after I did quite a bit of air sealing and then afterwards was running all of the bathroom fans, clothes dryer(air only), and the furnace had already been running 3 hours(recovering from deep setback on a -10 degree F day), when walking around the house and looking for spots that were leaking air the only spots I found air coming in was through joints in the foundation which were about 6 feet under grade. This bothered me enough to send in for a basement radon test, waiting for the results still.

Usually there is enough infiltration or ventilation to make this into a non-issue but a sealed house without ventilation(like mine) pulling its infiltration through the basement and then eventually making its way around the house bothered me since radon is patchy. If it turns out there is any concern over radon, I'll mitigate it with an efficient ventilator but I don't see the need for nearly as much ventilation as some people suggest. Even a quarter of an air change worth of air in a house seems to be enough for me on a daily basis. Instead I read about 1/4 of a houses air being exchanged, not sure how that is necessary or how a homeowner in the north wouldn't go broke in January.

Radon ?????? Who had Radon? Who knew about Radon? We are talking 40 years ago! Back in the day - we just had fire, water & dirt. Our earth tube provided more than enough seasoned air - not all of it good – poor design. We moved the "stinky" outlet (scientific name) from the interior of the house to an exterior enclosure that contained an early model heat pump. This had mixed reviews. So we reset the earth tube so that it sloped away from the house, so that it had a water drain and a filtered intake. Today's heat exchangers would cure all of these problems. The earth tubes work – being PVC, Radon can’t get in and if you live in the right area & are smart enough to design it right the first time – you won’t be disappointed.

I hear ya on the radon not making it through the PVC but unless you have quite a bit of grade to keep the condensation from either stagnating or draining to the house. Otherwise you need to drill weep holes which will let the radon in. I've heard that if you have 50' of grade you don't even need a fan as convection will move the air. It's a pretty interesting technology.

We need to keep in mind that I did this 40 years ago. In the remake, I ran a vertical down tube directly into 10 feet of earth. Half way down, I ran the horizontal tube uphill and yes it can be quite breezy. I’ve often wondered if one could harness this breeze. I could see a series of smaller tubes running up the hill, and then necked down at the outlet to turn fan driven alternators. To get the breeze you only need cool air at the bottom & warm air at the top. The great thing about playing with ideas is that I am not an engineer – So I don’t know it won’t work :-)

Keep your day job...

-AC

A prefab or a modular house would be very attractive. prefab or a modular house provider have the potentially that make a home great.