In a hole in the ground there lived a hobbit. Not a nasty, dirty, wet hole, filled with the ends of worms and an oozy smell, nor yet a dry, bare, sandy hole with nothing in it to sit down on or to eat: it was a hobbit-hole, and that means comfort.
Our plan is to live in a hobbit-hole, round door, brass knob, and all. And our plan is to build it ourselves, from the ground up—ground included! But that’s silly, right? After all, it’s a thing written about in fantasy books.
Our plan is actually a bit more involved than just a hobbit-hole, and while we do plan on having a No Admittance Except On Party Business sign permanently stationed outside the door, there are several quite practical reasons for our dream to build an earth-sheltered home.
Mass Effect
One of the biggest advantages to building an underground or earth-sheltered home is the energy savings. That’s because earth acts as a giant insulator, right? Wrong. The earth is actually a very poor insulator. However, it provides excellent thermal mass, and that is the key component to energy savings. Under the surface of the earth, depending the depth, the temperature stays fairly constant: around 50 ºF. And because the earth changes temperature very slowly—called thermal lag—it is offset with the seasons just enough to provide comfortable indoor temperatures year-round with minimal heating.
But some heating will be necessary, which is why we plan on building a central masonry stove to heat the home. Masonry stoves also contribute thermal mass to the home. They work by burning hot fires for short periods of time, while the exhaust—there isn’t much smoke at all—heats the masonry as it winds through a long flue before exiting the chimney. Masonry stoves can effectively provide all necessary heat for a home with as little as 1 cord of wood per year, which is ridiculously efficient.
And to complement these two thermal masses, we plan on having a concrete floor and concrete walls, with stonework on the outsides. Tons of thermal mass!
Natural Disaster
Where do you go during a big storm? Underground. A huge advantage of earth-sheltered homes is safety from natural disasters. Falling trees, lightning strikes, tornadoes (though unlikely where we live) are all non-issues. The only real concern with an underground home is flooding, and we’re looking for elevated property without wetlands to avoid that issue entirely.
Mowing the Roof
With a conventional house, there is much exterior maintenance necessary: cleaning the roof and reroofing, cleaning and painting the walls, and managing gutters (if you don’t have those fancy leaf-guard ones)—just to name a few. With an underground home, you don’t have to deal with any of these. The only thing required is the occasional mow to keep the roof-grass in check! Less maintenance means lower lifetime housing costs.
Peace and Quiet
An underground home is a private home. The earth acts as soundproofing, both from your neighbors and for your neighbors. Additionally, the house becomes part of the landscape, no longer a prominent sore thumb in nature but blended in, hidden away.
That kind of privacy is something we’re looking for, especially coupled with twenty-odd surrounding acres of pasture and woodland. Plenty of room for us to stretch our feet and not disturb or be disturbed:
No Admittance Except On Party Business.