junkyard ecology from lot 64

11/22/2005

Ferrocement


Browsing the interesting suspro.org I came across some nice ferrocement links:

- Javier Senosiain Aguilar
- Building By Design
- Ferrocement.net
- Ferrocement.com

From ferrocement.com's quick intro:

What is ferrocement?

Ordinary portland cement, usually mixed with plaster sand.

What are the mixing proportions?

Three sand to one cement, often written as 3:1. 2.5:1 is very rich, above 3:1 is less strong.

Why is it called ferrocement if it is regular portland cement?

Lot's of steel rather than lot's of concrete; in latin languages iron is a ferro rooted word, fierro in spanish, ferro in portuguese, etc.

How long does it take to dry?

Concrete doesn't dry; it cures in 28 moist days. If concrete dries before this period it won't cure to maximum strength.

Where can I learn more about ferrocement?

This web site has a graphic shape section to illustrate engineering concepts with shapes rather than words. The tank construction book has many tricks of the trade which will be useful to everyone from the artist to construction contractor. Each section of this website illustrates or explains from the actual experience of many people. Please make additions or point out omissions.

Why doesn't this website sell ferrocement or have advertisements?

The caretaker of ferrocement.com is the product of a large rural neighborhood where the techniques of ferrocement became part of the culture between the early 1950's to the late 1960's. WWII veterans were often building inspectors at that time. The old veterans knew ferrocement had helped win the war and were eager to assist an indigenous and vital young industry. When the veterans grew old and retired they were replaced by college educated, government science graduates. Third generation neighborhood businesses were crushed and disbanded by the new government science people who were not familiar with ferrocement and didn't realize it can cost more to engineer than build ("transitioned out" was the actual term they used at the time). The website caretaker is now growing old and this public service website passes on what was learned then so it is not lost to the future.

Where did this happen?

In the mountains behind Santa Barbara, California: Water tanks, sculpture, and low-cost, fire-proof houses were the staple products.

How did ferrocement help win WWII?

Barges, barracks, and ammunition storage structures (often buried).

Why is ferrocement engineering so expensive?

Most engineers use tables and formulae which summarize the compiled observations of what has stood the test of time, this does require education and intelligence but does not require much original thought. Though the free and artistic forms of ferrocement structures are many times stronger than most other buildings, they are complicated and time consuming to figure out on paper.

Where did ferrocement come from?

It is, basically, the old wire and plaster technique from the time of Michelangelo Buonarroti and Leonardo de Vinci, with modern materials.

11/21/2005

Who's John Todd?



This is an article about pioneer ecologist and biologist John Todd, who has done a lot of research and design of sustainable habitat, to say the least.
In 1971, I was a oceanographer at the Woods Hole Oceanographic Institute, when I read a small book by the ecologist Howard Odum, titled "Energy, Power and Society," in which he laid out a whole new view of how we might create the infrastructures for a sustainable human society. I had just co-founded The New Alchemy Institute a year earlier with two friends, one of whom is my wife, and its goal was to create a new science and practice of earth stewardship. Our objective was to bring together many disciplines under an ecological framework to address the issues of energy, architecture, food production, waste transformation, and environmental stewardship. Throughout the 1970s, at The New Alchemy Institute, we were able to demonstrate in each of these fields that an ecological design, science and practice does work.

Indeed, Todd's work at the New Alchemy Institute was noteworthy. This terrific article about the Institute from 1980 in Mother Earth News and this one published by Alicia Patterson's organization in 1979 give a taste of what they were up to. The Institute lasted from 1971 to 1991, achieving some notoriety, with one project (picture below) in 1976 even blessed by Canadian Prime Minister Pierre Trudeau, and later in 2001 praised by the U.S. Dept. of Energy as one of the most visionary buildings of the 20th century, discussed in this retrospective article.

A solar home/greenhouse

Dreaming about designing and building a structure that implements aquaponics, bio-digestion of all organic solid wastes for cooking, heating, and electricity, wind, water, and solar power, rainwater storage, as well as a comfortable, energy efficient, passive solar heated living quarters, I come across some interesting designs.

This page from the Solviva site has a picture of a structure that begins to hit on the major elements of my dream home/greenhouse.



The story itself is a rather illuminating, if hopelessly idealistic conception of two cities, one (Greyburg) representing the current systems of energy & food production, transportation, and waste management, and the other (Greenville) representing green alternatives.
Less than half of the city is serviced by the preexisting centralized sewage treatment plant. This plant was fully upgraded with Biocarbon filters at a cost of about 80 percent less than conventional technologies. And it costs about 90 percent less to operate, partly because the expenses are offset by the income from the resulting popular compost product, Greendale Black Gold, as well as from energy forest wood chip fuel which provides the backup heat for the city and methane for electricity production.

The people of Greendale avoided the enormous expense of expanding sewage pipelines, because on-site septic systems were instead upgraded with individual Biocarbon filter systems. By choosing these systems for upgrading wastewater management systems, instead of going with the conventional sewage, septage and septic systems that were chosen by Greyberg, the citizens of Greendale have saved some $200 million, and the groundwater and the lagoon are kept pristine.

Included on the Solviva site are great info on ecological septic systems utilizing what author and Solviva founder Anna Edey calls biocarbon filters, as well as several interesting anecdotes, links, and projects.



11/10/2005

Things to do with used tires (besides soup)



Earthship Biotecture:

Earthship n. 1. passive solar home made of natural and recycled materials 2. thermal mass construction for temperature stabilization. 3. renewable energy & integrated water systems make the Earthship an off-grid home with little to no utility bills.

Biotecture n. 1. the profession of designing buildings and environments with consideration for their sustainability. 2. A combination of biology and architecture.

Earthship Biotecture, based in Taos, NM, USA is a global company offering proven, totally sustainable designs, construction drawings & details, products, educational materials, lectures / presentations, consultation & guidance toward getting people in sustainable housing. From single family to colony / community / city complexes.

They utilize recycled tires, bottles, and local dirt, abundant, practically cost-free materials, but also require glass, photovoltaic cells, batteries, pumps, and controllers, none of which are inexpensive items.

This article in Permaculture magazine details the process:

With proper staging, it can be constructed in eight days. The structure begins with a 16ft (4.9m) diameter circular-bearing wall made by ramming discarded automobile tyres with compacted earth. Begin the circle by placing a stake in the middle of where the structure will be. Measure a length of 8ft (2.4m) string, and a little more for the knot. Tie the string to the stake – the string is now your guide to locate the tyres to be rammed with earth to form the walls.

Now you need to place your door frame and a small window frame in the equator facing wall. The first tyre pounded is placed on either side of the door frame. Begin pounding tyres! This bearing wall technique has been approved as an alternative building material all over the USA and in many other countries, including Honduras. It requires no foundation, as the massive wall is already wider than the required foundation.

In some situations the owner/builder may choose to tap into the thermal mass of the earth and sink the structure into the earth about 4ft (1.22m). This is site specific and the water table and stabilization of the earth will dictate if this is possible. If you are not tapping into the thermal mass of the earth and building completely above ground, you will need to wrap the circular tyre wall with straw bales or fibre bale to try and mimic the thermal mass of the earth.

Once the tyre wall is finished, it is packed out. The voids created by the circular tyres next to each other are filled with mud (water, dirt, straw) with cans, bottles, rocks or other object to fill the space. While the tyre wall is being packed out, dirt is bermed against the structure or fibre bales are placed around the tyre wall. Fibre bales must be placed according to typical strawbale architectural guidelines

A concrete bond beam with steel rebar inside is built on the top course of the tyrewall with a small aluminium can wall to form the bond beam. Then two ‘bird-cage’ domes are place on this bond beam.

The first dome is built of very small wood beams, where wood is available, and in other places where wood is not available, built of steel rebar. The second dome is taller and bigger, made of a steel rebar skeleton. The steel rebar dome skeleton is wired together and covered with a very wide metal lath, like chicken fence mesh. Then, recycled cloth or other similar material found in the local region is dipped in a cement slurry and applied just like paper-mache. The domes are allowed to dry and insulation is stuffed in between. The insulation can be industrial hemp, shredded cloth, shredded paper, spun-glass (batts), etc.

Then the domes are plastered a few more times for strength and the outside dome is covered with an elastomeric roofing membrane that allows you to catch potable water. Form a gutter around the edge of the outer dome to catch all the water and direct it to a cistern outside, either buried in the berm, in the ground or above ground. The water is filtered through a simple drain, falling directly into the cistern. Be sure you put in the proper slope for your water to move efficiently into the cistern. At this point you can install the door and window, finish plastering the inside, install a floor and other finishes. Typically lofts are built on the inside, independent of the structure of the building and are about 15ft (4.6m) tall, depending on the shape of your domes. This provides a very sturdy shelter, a rainwater catch and a space for two people. The cistern can be accessed with a scoop or hand pump from inside the space.



Here's a link to the Packaged Earthship available (as plans and AutoCAD drawings) on dreamgreenhomes.com:
This 2 bedroom, 1 bath, 1118 sf Packaged Earthship design demonstrates passive solar heating, solar energy collection through photovoltaics, water catchment, and sewage treatment. The width of each room is flexible, as is the length of the entire shell. Each Earthship includes an interior planter which allows the resident to use fresh water at sinks and shower, send it through the interior grey water planter to feed the plants which in turn clean the grey water as well as produce oxygen, flowers and sometimes food, then the remaining water can be used to flush the toilet. The black water from the toilet is sent outside to a conventional septic tank and then into a contained drainfield where the moisture provides landscaping. The load bearing walls in the home have been built by ramming earth into used automobile tires. Interior walls are built using recycled cans.

11/04/2005

Rainforests for the Rich





Dutch site vivaria.nl: They do vivaria, or terraria, or aquaria, or paludaria, or whatever else you might call it. They manufacture coco bedding panels and also sell some lighting and ventilation equipment and controls, as well as live amphibians (starting in the US$500 range, with s&h).

10/29/2005

Solar Renovation

Hacking Your Way Off the Utility Grid: This O'Reilly article documents one guy's installation of photovoltaic, solar heating, and solar air systems in his San Francisco home.

The system I decided on is a 2,500 Watt (peak output) system consisting of 18 BP (British Petroleum) solar panels coupled to a 2500 Watt Sunny Boy inverter (which converts the DC power from the panels to 120 volt AC power). The system is net metered and is connected to the PG&E electric grid. When the system is generating surplus power, which it typically does during mid-day (even in the winter), the meter runs backward. PG&E bills me for my electric use on a 12 month cycle, so usage is averaged out over a one year period.

The goal in net metered solar electric is to size the system so that it generates up to 100% of the power the house consumes on average, throughout the course of a year. PG&E does not pay for surplus power, so the game is to get as close to net zero consumption as possible.

My strategy was to start with a system that generates 65 to 75% of the home's average electricity consumption, and then eliminate the remaining 25 to 35% through the conservation measures in phase two and phase three of this project.

The rooftop solar electric system was installed by Occidental Power, a solar electric contractor based in San Francisco. Solar electric systems require the help of licensed contractors because the system is connected to the public electric grid and, therefore, must conform to numerous electrical and fire safety codes.

The system cost approximately $25,000 prior to the California rebate, and $16,000 after the state rebate (for a net cost of about $6,500 per kilowatt). At first glance, this seems expensive, but the system has a 30 year life span. The initial cost of the system was rolled into my mortgage when I refinanced my house, and when amortized, costs about $80/month, about the same as my electric bill. However, instead of sending money to PG&E, I am paying down an asset attached to my house (installing the array increased the value of my home proportionally). This monthly payment is also tax exempt (it's part of my mortgage), and so the real, post-tax cost of the array is more like $50 per month, less than my monthly electric bill.

From January through November of 2004, my system has generated 4,400 kilowatt hours of electricity. During this period, my home has drawn 2,200 kilowatt hours from the public grid (for total consumption of 6,600 kilowatt hours). My system is currently generating roughly 65 to 70% of the electricity my house consumes. The system reduces the cost of my electricity even more because it lowers my home's average consumption enough to get me into the lowest pricing tier ($0.13/kWh versus $0.19 to $0.25/kWh). So what electricity I do pull from the grid is now billed at the cheapest rate.

This is an important point, especially if you draw 500 kilowatt-hours per month or more (as most modern homes do). If your utility company uses a tiered rate structure, it is likely that the majority of your power is billed at high above-baseline rates that can be two to three times the baseline rate. The power generated by the PV system will offset the most expensive grid-supplied electricity first. So even if your system generates only a modest share of the home's power, say 35 to 50%, it can reduce your electric bill by substantially more than this.



10/28/2005

Natural Pools

Some of the basic principles and theory behind constructing swimming pools that utilize plants for filtration in this Mother Earth News article. Specifics on plant selection and zoning; bentonite clay, plastic liners, concrete, and other building materials and design elements; aeration; algae control; and maintenance.




Sunhawk, or "Pimp my Solar Home"

Sunhawk: built in 2002, "a 2,900-square-foot dream home of John Schaeffer and Nancy Hensley ... feature[s] passive and active solar techniques", "powered with a 15-kilowatt solar array that provides about 50 kilowatts per day," with "a 10-acre-foot main pond", walls of Rastrablock, they say in this article it cost in the neighborhood of $600,000 to construct. Did I mention it's shaped like a hawk?
On the winter solstice, the hawk will appear on the floor and "fly across" the room to the fireplace "symbolically transferring the sun's energy to the fire," says Henritzy, who will be at Sunhawk on Dec. 21 working out the accuracy of the design.

More info at the Solar Living Institute site.