Frequently-Asked Questions

Here, the Potters answer common questions about their house.

Does it work? How?

Yes, it works. :-) The basic priciple is 'mass under glass': the living quarters of the house are surrounded by massive floors and walls, whose temperature is maintained at an even and pleasant level by the sunlight coming through the glass windows, the shade of the roof, and the insulation outside the walls.

Why did it take so long to build?

We are retired and chose to build the house with cash on hand as it became available. We did not wish a mortgage, even though these houses can now be mortgaged under the CMHC.

Can I build the house in my condition?

Probably. Anyone in reasonable physical condition can handle the tires and earth and build the walls. We've had people as old as 70 help out. The roof and windows are harder.

Can I build a house using only the information in the original Earthship books?

Yes.

Can I build a two-story house?

Yes. We chose to build on one level, as the house is our retirement home, and we are thinking about the need for limited-mobility accessibility in the future.

Do I have to build it myself?

Not anymore. Construction crews are being trained, and will be available in the spring of 2006.

What is peoples' biggest mistake in building these houses?

Building more house than they need. Our house is unusually large, because it is also an office. Many people could get by with fewer rooms. There is nothing actually stopping them from building a 7000-square-foot mansion, though: several people have.

Can I build the house in sections?

Yes. When you build individual rooms,just extend a partial wall from one side of one of the existing rooms. Build enough of the partial wall to connect with the full height of the existing wall. Cover the partial wall with tarps during the off-season. If you temporarily close and insulate the existing room, you can live in it over the winter. When spring comes, take the tarps off and resume building.

How long does it take to pack a tire?

It takes about 15 minutes to fill a tire with earth and pack it solid.

What's all this plastic you are wrapping the house in?

It's a vapour barrier. It keeps water vapour from migrating through the walls into the insulation, condensing in the cooler parts of the insulation, and damaging it. Vapour barriers are a standard feature in all new houses in our climate.

The vapour barrier goes under the floor, too?

Yes. Inside its insulation, the house is completely wrapped in the vapour barrier, which is sealed around such things as doors and windows. Arrangements are made to provide air exchange for breathing and such.

Are you offering workshops?

Yes. Contact us for details. They are available weekends, Saturday and Sunday, until the end of October (2005). Telephone +1 613 474 0435.

Are you offering tours?

Yes. Tours in English are available every weekend, 9-5, for a 10-dollar fee. Contact us for details.

French- and Esperanto-language tours are also available by appointment.

What about building permits?

The house was designed by an architect and an engineer, and was granted a building permit.

How many of these houses are there?

We know of 18 such houses in Ontario using the tire technique to contain the rammed earth. There are thousands of these houses in the United States. There are many other rammed-earth houses.

What would you change?

We would use a less-expensive roof: an exposed metal surface on lighter trusses, instead of the heavy construction that can carry an earth load. We would also have made the rooms narrower so that we could have used standard-length roof trusses, which are much less expensive than the custom ones we did use. We would also install an indoor swimming pool. The humidity would be good for the plants.

Speaking of plants, what have you grown inside the house?

At different times, we have grown geraniums, broccoli, ginger, basil, sage, swiss chard, beans, ivy, jasmine, avocado, canna lilies, calla lilies, roses, grapes, tomatoes, cucumbers, and peace lilies. The coffee didn't do so well, though, because it needs an alkaline soil, and our local soil is acid. Other people have grown oranges, lemons, and bananas.

Do the plants need to be fertilised?

We have never fertilised them. We placed normal soil in the planters, over layers of rocks and gravel where the greywater from the sinks and shower flows. The greywater provides plenty of nutrients to the plants. It is important to stock the planters with mature plants, so that they can handle the greywater right from the beginning.

How many solar panels do you have?

Five 50-watt panels provide direct-current (DC) electricity. They feed a battery system, DC lights and outlets, and an inverter to create standard 120-V household wall current (alternating current--AC).

DC and AC?

Yes. Running DC lights and appliances is more efficient: we don't need to convert the DC to AC, only to feed it to some device which will just convert it back to DC again. Converting AC to DC is what the black boxes on the power cords of so many electronic devices do.

Our DC system uses the same voltage and connectors as 12-V automobile accessories, so we can use car chargers and adapters and such.

Your electricity supply is only 250 watts total? I have a hair dryer that uses more than that!

Your hair dryer uses too much power. :-) Seriously, electric resistance heating (hair dryers, electric stoves, toasters, irons, and so on) is the easiest way to use a lot of electricity. Most non-resistance appliances and electronics use a lot less.

We do not use a toaster or hair dryer or electric stove (we have a wood stove). We plan our usage as well to avoid high peak loads: we don't use the satellite receiver and television set at the same time as the computer, for instance. This enables us to use a smaller and cheaper electrical system.

And besides, our hair looks better and has no split ends now that we don't dry it using high heat.

Speaking about appliances, what about your fridge? Doesn't it use a lot of power?

No. We do not use a conventional fridge. We have an insulated box with massy walls in which we keep food cool. It uses the same principle as the house, actually, but at a colder temperature.

During the winter, when the temperature can drop to as low as -35 Celsius, we open the box to the night air and let it cool. During the sumnmer, we use a solid-state cooling device to keep the fridge cool. These are another DC-powered automotive accessory, sold to keep picnic coolers cool.

What about irons?

We choose clothes that we do not need to iron. Chuck's favourites are Tilley Endurables.

How do you clean your clothes?

We clean our clothes at the laundromat in town. It could be done in house, but we have not yet purchased the appliances.

What about a furnace?

We don't have one of those either. Sunlight on the mass of our walls, plus the heat of the earth, provides enough heat for us. If we do want to warm things up a little, we just bake bread on the wood-fired cookstove.

One winter, before the house was finished, only the first two rooms were enclosed with roof and windows, and there was no insulation outside the walls. The rear wall had not yet been bermed, and was exposed to the winter breeze. The outside temperature dropped to -35 degrees Celsius. Even then, the inside temperature never dropped below 6 degrees Celsius. A guest chose to sleep in the house, and all he needed was a big pile of blankets.

Yes, the house is that efficient at trapping the heat of the low winter sun as it shines all the way into the rooms.

Won't the house overheat in the summer, then?

No. The summer sun is high and does not shine far into the rooms. The walls remain cooler than the outside summer temperature. We don't need an air-cooling system either.

Over time, the walls and the air in the house tend towards an average year-round temperature, not far from the average earth temperature here. We found that the house temperature varies between approximately 15 and 25 degrees Celsius.

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