The Mobile Tiny House That's Green: December 2008

The concept of a small home on wheels is not a new idea. The first documented mobile home was a horse drawn version that was used in a move from London to Cyprus on April 20, 1879. The covered wagon was used before this, and so on...........

Can a person(s) live in a small home (100 to 200 square feet) and be content? Is this taking things to the extreme?. Where does one put such a house? What about power? water? heat? a hot shower? the toilet? laundry? dirty dishes? sleeping quarters? closet space and many more important questions. Could a small, efficient home be completely green? What about solar power? rainwater catchment? composting toilets? propane cooking and heat?

There are a number of people who are doing this right now, successfully. They have chosen a different way of life. They have dramatically decreased their carbon footprint and simplified their lives. Think about how easy it would be to clean a small home. No yard maintenance (goodbye lawn mower!) Imagine, no house payment, small utility bills (if any), no cable tv or land line phone bill, riding your bike more often, and maybe having the freedom to work a job that you enjoy. Ever feel like a gerbil on a wheel? A slave to your possessions? Think about the freedom and the flexibility this situation offers.

Location
There are many places to park a mini home. The best is probably your own piece of property that ideally, is paid for. This has the potential of a sewer hookup, along with water and even natural gas. Another scenario would be to park it on a friend or family member's property. How about buying a house and putting it in the side yard and renting out the house to a tenant to cover your house payment? A mobile home park would work. Also, an RV park. Being parked adjacent to a conventional home has many advantages: you can use their bathroom, laundry, kitchen, garage and storage if necessary.

Electricity

A big advantage of a mini home is it's small power consumption. Most are designed to run off a single heavy duty extension cord. Another option would be a 30-40 amp service, which allows more flexibility for appliances. A solar powered home would be ideal, but that requires low power usage and limits things like a refrigerator, microwave, toaster oven, electric water heater, etc. Additionally, solar power requires large panels and batteries which can create problems for a small home. Mounting the solar panels on the roof is the logical place for them, but can add weight and stress to the roof. Each solar panel weighs about 50 pounds. Batteries are also heavy and take up valuable storage space. 6 solar batteries (with their special steel storage cases) can weigh about 800 pounds. Further research and development needs to be done here.

Water Supply

A good supply of water is essential to any dwelling. There are 3 options here. The first is to use a garden hose or RV hookup. This is easy and it gives you a steady supply of water. The second option is bringing your own water in jugs or containers periodically to the house. This is kinda of hassle, but it takes you off the water grid and makes you conserve better. The third option is a rainwater catchment concept. This idea seems good at first, but you need a large roof with gutters, an elevated holding tank and do you really want bird droppings mixed in with your water? A well could come in handy, although those are getting harder to come by.

Heat

The most logical way to heat the mini house is with a small efficient propane heater. Natural gas is not really an option if you want to stay mobile and electric heat uses too much electricity. A wood stove could be used but requires firewood, it is also messy and potentially dangerous in the small confines. Propane heat is the way to go.

The "shed on wheels" below has a loft for sleeping and a wood stove (see the stove pipe projecting thru the roof) for heat.

Water Heating
A tank less propane water heater is the most efficient and the best choice here.

Toilet

This is probably the biggest challenge for a successful a mini home existence. What to do with the "black water"? You can use an rv tank. You will have to periodically empty this (we're already looking forward to that!). But it is contained and it's legal. Another option is a composting toilet. The research is still out on this one. Some swear by them, others swear at them. Basically, a CT looks like a standard toilet. When you flush it, the organic material is moved to a compost box were it is mixed with a sawdust-like material and hopefully turns into a odorless clay compound. Some CT's require electricity, some don't. Another option is an incinerating toilet. IT's are electric or gas fired. They raise the temperature of the organic waste, turning it to ash for disposal. These do use energy and thus leave a carbon footprint. Again, there are different opinions on the usefulness of the IT's. A mobile home or RV park would have good solutions for the toilet hookup. An old style out house may be an option in remote areas ( I recommend a two-holer).

Gray Water Disposal

Often overlooked, is the handling of the gray water. This is the used sink and shower water that has a separate tank in most RV's. It would be nice to re-use this water to flush the toilet. This would involve filtering it and using a pump to deliver it to the bathroom. The pump would use additional power, which could be a deal killer. I wonder how many campers, RVer's and trailer dwellers turn this raw gray water loose into the ground. Is that doing damage to the environment? Is dumping soapy shower water or dishwater illegal?

Laundry Facilities

Very few mini homes have a washer and dryer due to space and energy consumption. A third reason would be water usage, especially if your not hooked up to water. It looks like the laundromat or close by neighbor. The possibility exists of hand washing clothes and then air drying them on a rack or clothes line. What about a mini gas or propane dryer?

Dish Washer

This is another rare option. They do make a counter top or a built-in model (see pictures at right). It uses electricity and hooks up to the kitchen faucet and drains into the sink. This seems like an unnecessary appliance but most people don't like to hand wash dishes.

Wood 2x4 vs Metal Stud Construction
Metal studs are lighter and cheaper than wood 2 x 4's. Wood gives better strength for framing and fastening cabinets, plywood, siding, etc. Even though the wood studs are heavier and more money, they are the better choice here. FSC (Federal Stewardship Council) lumber is better for the forests and environment. Buy a home built with this type of lumber when possible.

Insulation

Owens Corning pink insulation is the standard choice for insulating the floor, walls and ceiling for conventional homes. This fiberglass product works very, however, it is not the most "green" type of insulation. A newer soy-based, spray foam insulation is becoming popular for it's insulating and "green" properties. Blown-in cellulose (newspaper), cotton fiber batt (denim), recycled fiberglass and mushroom "greensulate" are more enviro-friendly options as well.

Doors and Windows

Energy star with Low-E glass doors and windows.

Roofing

Metal or aluminum roofs are the standard style of roof for most mini homes. This blends durability with decreased weight (composite roofing is very heavy).

Siding
A wide variety of siding is available for the home exterior. T-111, lap, metal, aluminum, cedar, shake, Hardy Plank, vinyl siding or a combination.

Zoning and City Ordinances

There are some legal challenges to living in a mini home. Disposal of bathroom waste and gray water are the biggest problem. Composting toilets are not always legal within city limits. They also can emit persistent foul smells. Constant emptying of black and gray water tanks could become a hassle. A garden hose hookup can solve the water supply problem. Keeping a constant supply of propane seems easy enough. I think if a person found a yard to park the mini home in, the city may ignore the situation. I think this is a ambiguous area for many zoning laws. Unsanitary toilet conditions would result in some type of action by the city. Releasing gray water into the ground could result in city/county action.

Living Leaner and Greener

One could make the argument that if you're emptying black and gray water rv tanks, constantly running to get propane and you're hooked up to an extension cord and garden hose that you're really just camping. There is much truth to this argument. Counter point: mini homes dramatically reduce your carbon footprint. You use much less electricity, natural gas, and water in a small house. It would interesting to do a 10 year study comparing the resources used in heating and lighting of a 2000 sq ft home vs the mini home. Think about how many 20 cubic foot refrigerators run 24 hours a day that are basically empty. Think about how many electric hot water heaters maintain 50 gallons of hot water 24 hours a day while people are asleep or gone. The mini home shower, toilet and faucets use probably a third of the water consumed in a "big house". There as a decrease in the amount of garbage generated. Fewer cleaning products and paper towels being used. These small homes are energy misers and have a ripple effect on many other positive effects for the environment.

"25 years from now, drinking water will be more valuable than gasoline."

Below you will see pictures of Jay Shafer's tumbleweed home. Jay lives in this house full time. It is located on a fruit orchard. It has propane heat, a garden hose hookup and a rv toilet.