I know you were born wondering how to bury and earth-sheltered house. You will finally get your answers in today’s post.
You’re welcome. ;)
You need a lot of soil.
We had several decent-sized piles of soil from when Troy excavated the area where our house was built. In case you haven’t been following my videos on the construction, he excavated into a gentle slope, carving out a level place that ended up being four feet high in the back.
But that was nearly enough soil to bury our house with. Not even close.
Some people who build earth-sheltered houses simply dig up pits on their own property to make up the difference. Others have to buy topsoil and have it shipped in.
We almost had to do it – and the house would have cost us thousands of dollars more! But, we were nice to the rich guy(specifically, his property manager) next door. As a result, the property manager let us dig up all the soil we needed to bury our house.
You need expensive equipment.
Namely, you need a backhoe, bulldozer, and dump truck. Nice for us that Troy happened to have all three. And even though we ended up paying him more than anyone had estimated we would, he is still the most affordable machine guy around where we live.
If you want to learn how to operate this kind of machinery and then rent it, it will probably save you some money. But it will cost you dearly in time, stress, and labor. Take that into consideration.
You need lots of water.
I was appalled when I discovered that this so-called environmentally-friendly home would require thousands of gallons of water to bury. When you’re building up the berms along the sides of the house, you have to water in the soil every foot or two. If you don’t, then within a year of burying your house you will lose an entire foot of depth of soil. That means you lose a lot of the insulation value of the house.
You need a big pile of Styrene (rigid foam) and six-mil plastic.
After waterproofing the house with liquid rubber and letting the material dry, a layer of six-mil goes over that. Then, after the first foot of soil goes over the top of the dome, you put down a layer of Styrene, and cover it with yet more six-mil.
We needed 50+ 4X8-foot sheets of Styrene on the top of our one-module dome.
How we did it
At the beginning, Troy used the subsoil obtained from our property during the excavation. After that he used the free “soil” we obtained from the property next door, most of which was shale. First, he built up the berms on the west, east, and north sides of the house. They each extend out about thirty feet from the house.
Next, he began carefully pushing shale onto the top of the dome. I say “carefully” because the concrete dome won’t support the weight of a bulldozer until there is at least one foot of dirt on top of it. After he got the dome covered with the first foot, he paused to help us layer the Styrene over it. We had to tape them together so that they wouldn’t slide down the slope.
It also ended up being windy the day we did it, so we had to put rocks on top of the Styrene to weight it down.
Over the Styrene went another layer of six-mil, mainly to help hold the Styrene in place, but it also adds an additional protection against water leakage.
He had finished probably about two-thirds of the job back in late October when a rat got into the engine of his backhoe and chewed up wires. We’d had rain for several days, during which time the machines just sat on our property, and open invitation to little critters that wanted a dry place to build a nest.
So when Troy showed up after the soil dried up some, he couldn’t start his backhoe. Even though he discovered the rat and its nest, neither he nor his mechanic thought that the problem was related to the rat. Only after replacing several parts to no avail, and two and a half months after the breakdown, did the mechanic finally figure out that the problem was damaged wires.
Troy finally showed up again in early February – three months after the last time he’d worked on our property – to finish the job. He put down a couple feet more shale, then topped everything off with about six inches of topsoil.
A lot of work, and – of course – it cost more than we thought it would. But it finally got done!
The video that follows, the fifth episode of “Our Underground Life”, is part one of two about the burial of our house. If you have boys in your house that get a kick out of watching “mighty machines”, invite them to have a look, too.