9.0 Notes (page 5)

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Develop Alternatives: Introduction

We identified alternate approaches to all the main functions on the previous two pages. Now we need to quantify these alternatives in enough detail to develop input and output formulas for our numerical models. This will be an incremental and iterative process, since many values will depend on other values. In addition to the actual numbers, we will record the reasoning and references used to reach them. As in the previous pages, Habitation and Transport are addressed first, as they determine part of the outputs of Production. Actual physical construction and operation would start with Production, so that has the lower function numbers.

Estimates do not have to be made entirely from scratch. Sources include:


F.2.1.1.2 Habitation Data

This section includes data on requirements and alternatives which affect the main Provide Habitation Capacity function as a whole.

Habitation Requirements

Cost data are based on January 2013 as nearly as possible, and dollar amounts are allocated for the purpose of estimating the design, inputs, and outputs of the various functions. Actual design and cost distribution will be a matter of choice for the participants and residents. The distinction between participants and residents is only whether they live and work at the location, and this status can change with time.

Habitation Alternatives


F.2.1.1.2.1 Protection Data

This section covers data for the Protect from External Environment function within Habitation. This function includes passive protection from weather, water, insects, and structural support for all of the Habitation elements. The latter might be considered passive protection from the Earth's gravity and failure of the subsoil, which is why it is included here. The protection includes major elements like structure, roofing, and siding, plus secondary items to complete the protective capacity.

Protection Requirements

Protection Alternatives

We approach the data for this function by starting with a conventional design, then considering incremental alternatives to it. The protection from the external environment task includes structural support for the protective elements, and in turn the ground which supports the structure. The result is this equates to the lot and shell of a conventional house.

Weather Delays - Building the elements for this function is not itself protected from the environment. A weather delay factor of 25% is assumed for a Temperate climate, but this needs to be adjusted for the actual local climate. Once a sufficient level of transport infrastructure and roofing is in place, weather delays will fall off in importance.

There are numerous options for residence design, so we select those which on first inspection could be produced locally:

Land - The land itself is bought and financed conventionally. We will assume $1/m2 for undeveloped land, though this varies by location and condition. Since mortgage rates are currently (2013) less than high yield bond rates, the least cost approach is to invest enough to cover the mortgage payment. Habitation land area was estimated at 1000 m2/person, of which 200 is building floor area. Prior to doing calculations for them, we roughly estimate other land areas (in m2/person)as: production land outside growing organics = 500, of which 200 is buildings or built equipment, growing organics = 500, timberland for long term maintenance and modification = 6 x built area = 2500. Timber required for initial construction is higher and may require extra land or timber rights. Thus initial total land estimate is = 4500 m2/person (1.11 acres).
Site Work - This is clearing, grading, and installing utilities prior to building construction. This requires heavy equipment, so we look at providing a general-purpose tractor with appropriate attachments. Site work will obviously depend on the specific site, but we will assume 2 meters depth on average for the buildings area, and 0.5 meters depth on the remainder. This may seem high, but excavating and back fill requires moving the same material twice, and clearing of trees requires some depth to extract the roots and then move the debris (we will try to use the lumber from such trees). This gives an earth-moving requirement of 800 cubic meters per person. Utility lines themselves are covered under other functions (ie supply electrical power, water, and sanitation).
Equipment required will vary considerably by task, but we can use 100 cubic meters/day/machine as an initial estimate for clearing and grading. Given 270 work days/year after weather delays, and 75 people per year, this results in the need for 2.25 machines, which we will assume is implemented as 3 or 4 specialized heavy machines with different attachments. If the excavated earth is suitable, some of it may be used as raw materials. Unsuitable material may need to replaced, or fill added from elsewhere, to reach desired drainage and elevations.
Foundation - We assume concrete slab, footer, and solid or block foundation walls, with steel reinforcing as needed. Cement is the highest cost ingredient, followed by reinforcing and structural anchors, so we look to produce those materials those first. To estimate requirements, we assume 0.15 T x 100 m2 slab, and 1.5 H x 0.2 T x 40 L meter solid foundations. This gives 27 m3 concrete/person.
Framing - For conventional framing we assume light lumber or heavier timber pieces, and either panels or boards as fill. This can be assembled in Production into modules, giving an opportunity for automation. We assume 0.2 m of framing lumber x 200 m2 floor area = 40 m3 wood/person. For 75 people/year we then require 3000 m3/year.
Roofing - We assume clay or cement tile roofing, since that can be made locally. It will require somewhat sturdier structure due to weight, so we allow 0.1 m framing x 100 m2 roof plan area = 10 m3 wood/person. This assumes two story construction on average. The roofing itself we estimate at 2cm thick x 150 m2 coverage = 3 m3 tile/person. The coverage is 1.5 times the plan area due to required slope and overhang.
Siding - We assume clay or colored cement brick or block siding. In the case of block, it partly replaces the framing. These are good options for local production, and with automated brick-laying, possibly for assembly also. Windows are part of the building sides. High quality insulated windows may be difficult to make, in which case insulated shutters are an option, along with double panes. Wall area is 6 H (two stories) x 40 L = 240 m2 area. For brick the thickness is 0.1 m, and block is 0.2 m, giving siding volume at 24 or 48 m3.
Insulation - Conventional insulation includes fiberglass and styrene foam. Glass fiber may be difficult to make on a small scale, but a substitute using basalt fiber may be possible. We assume 0.15 m wall and floor, and 0.20 m ceiling insulation thickness. This requires 71 m3 total insulation volume.
Barriers and Sealants - This includes items needed to complete the protective capacity of the major elements above, such as paints, flashing, tar, water and vapor barriers, vents, gaskets, and caulking.
Protective Clothing - Protective clothing may seem unrelated to the Habitation function, but they are needed any time the weather requires it, or tasks expose workers and residents to abrasion, chemicals, shock, or other hazards. The conventional option is simply to buy appropriate gear.


Leasing - In early stages of development it is worth considering leasing land rather than buying it. This requires less capital investment at first. Leasing can make sense if funds can be invested at a higher rate of return than the lease cost. This can be either a pure financial investment, or investing in other location equipment and operations. It can also make sense as a temporary location: for program participants and future residents, or for storage and production space, until permanent locations are ready. Modular or mobile living and production space, where the land has minimal development and utilities, falls under the leasing option. This raises issues of transport, safety, and quality, so would tend to be used for very temporary situations. The detriments to leasing are the ongoing expense, eventual need to move, and limitations on how much you can change. Lease costs are highly dependent on location, so we cannot make an estimate until the location is known. They also depend on what land is available to lease vs. purchase at a given time. So this alternative will need to be examined at the time land is needed.

Resource Rights - Rather than buying full ownership to land, buying partial rights, such as timber or mining, rights of way, or equipment placement, may turn out less expensive. This is more likely during initial construction, when extra supplies of materials are needed, or when attaining surplus output as a program goal. Another reason to acquire rights is if the permanent location lacks specific resources. One way to get resource rights without cash expense is by offering a share of the extracted resources, or sales therefrom, to the owner. Another is to offer site improvements, or barter other work for the owner, in trade for the rights.

An alternative to heavy equipment is to use lighter robotic equipment such as draglines and conveyors, where the equipment anchors itself temporarily rather than relying on sheer equipment mass to counteract the forces of earth-moving. Anchors can be drilled or screwed into the ground, or use local water, earth, or rocks added to lighter containers. Another alternative is to use a larger number of smaller equipment units. This lends itself to quantity production. To reduce human labor, smaller units should be at least partly automated.

An alternative to mass concrete foundations is to use treated wood or reinforced concrete poles embedded sufficiently deep. This can be in conjunction with ground-level construction (pole barn style), or raised platforms to "float" the building above the terrain. The latter may be desirable to reduce excavation in difficult terrain, avoid ground water, gain better views, or use the space underneath the platform. Regularly spaced poles lend themselves to modular construction and modifications. Another alternative to mass foundations is discrete deep pilings, which get their load bearing capacity from depth rather than distribution horizontally. An alternative to concrete is to use mortared stone, which mainly differs in separating the cement/sand mix into mortar layers around larger stones, rather than an intimate mix in concrete. To distribute loads and isolate ground water, a gravel trench or layer may be used between footings or slabs and subsoil/bedrock. This is commonly seen in highway and railroad construction, but can also be used for buildings.

Conventional alternatives to wood framing includes light gauge steel studs and trusses, heavier structural steel tubing and shapes, concrete block or structural brick, or reinforced concrete columns, walls, and precast panels, with or without included insulation. Less conventional alternatives include stabilized rammed earth using a percentage cement or other binder, mortared stone, truss framing, composite materials, domed structures, and underground construction, where the bedrock serves as the framing. Any given building can use a mixture of framing systems. The heavier alternatives do not lend themselves well to fabrication elsewhere, or later modifications. They would need strong personal choice or cost advantages to be preferred. Steel, concrete, brick, cements, and excavation will most likely be needed for other reasons than framing, so the processes and general equipment would be available. What would shift is the quantities needed and detailed equipment.

Alternate roofing materials include:

- A composite of tar and gravel (standard flexible shingles), with fiberglass reinforcing. This is not preferred unless easy ways to provide the ingredients and process them are found.
- Fiber-cement shingles using wood pulp or glass fibers.
- Solid wood shingles, which are easy to make but have durability issues. Painted wood shingles may last longer if properly ventilated.
- Metal shingles or extended panels. This is an option if the right type of metal can be produced in quantity. Purchased metal roofing is relatively durable and not much mass is required (most of it is in the roof structure to support the metal).

Conventional alternatives include molded vinyl, wood board or shingle, fiber-cement board, stucco, sheet metal, or mortared stone.

Papercrete (paper-cement mix) is a substitute with decent insulation value, and easy to make. Natural mixes like straw-clay may provide adequate insulation while sufficiently fireproof. Wood is moderately insulating across the grain, but a large amount would be needed for modern levels of insulation. Rock wool is similar to fiberglass, but made from local rock.

For foundations, dense concrete is relatively waterproof, but additional coatings like tar can be added, or layers of waterproof plastic. Adequate trenches and drainage pipes may be needed to guide water away from the structure. Plastic sheeting may be used under slabs or crawl spaces to reduce moisture rising from underground. A water barrier underlayment is generally used under roofing and siding to drain off any water that penetrates the outer protection. It is also used to slow water vapor and air infiltration. Paints of various kinds protect other materials from direct exposure to water and sunlight. Flashing is thin metal which rises above penetrations of the exterior, such as at roof vents and windows. The risers guide water away from the penetrations. It also is used as a drip edge at exposed corners, so water does not seep under exterior protection. Tar and caulking are used to seal small gaps. Gaskets help seal larger penetrations, and vents allow moisture and hot air to escape while keeping water out.

Portable shelters are an alternative to wearing thick clothing in bad weather. This may consist of a flexible waterproof layer, insulation, and lightweight frame which can be moved from place to place as needed. A portable heater is used to counteract cold conditions.


F.2.1.1.2.2 Control Internal Environment Data

This section covers data for the Control Internal Environment function within Habitation. It includes control inputs and sensors (such as thermostats), and active hardware which produces the desired changes, such as heating, ventilation, and air conditioning (HVAC) systems. Passive thermal insulation was included in the previous function, and lighting, windows, and window coverings are included here as active devices. Emergency systems are also included here.

Control Requirements

It is not stated as an explicit requirement, but the control function must keep the internal environment within limits of human comfort and adjust to personal preferences. This includes controlling at least temperature, humidity, lighting, and acoustics.

Control Alternatives

From US household energy use data, we can make a rough estimate for 160 m2/person of private space that an average of 3,500 W of total energy is consumed. This may be all electric or a mix of energy sources. The remaining 40 m2/person of public Habitation space, for want of a better estimate, is at the same rate, giving 900 W/person, for a total Habitation energy use of 4,400 W. Grid-wide utility daily power use peaks at about 25% above average demand, and we can make a rough estimate that our location will have a similar use curve. Seasonal household energy demand is estimated to peak at twice the average, and hourly use can peak at twice the daily average. Therefore peak energy capacity is very roughly estimated at four times the average use. Peaks may be met by a combination of storage and outside supply, but this will not be decided until later in the design process.
Total US energy use in 2011 was 10.3 kW/person average, and we will allow a 50% increase for a high quality of life and active production. So our first estimate of location power requirements is 15 kW/person. These energy estimates will need extensive updating when more design details are known, and the extent of surplus production and growth. Current use rates can probably be improved upon by efficient design and integration of functions.


F.2.1.1.2.3 Food and Drink Data

This section includes data for the Provide Food and Drink function within Habitation. It includes supply of actual food and drink materials for residents and guests, local storage within Habitation areas, food preparation, serving and dining, and disposal of food and drink wastes. The latter does not include human wastes, which are covered later.

Food and Drink Requirements

Food and Drink Alternatives

Shared equipment reduces the conventional setup of a complete kitchen in every dwelling. It has full community kitchen areas shared between some number of dwellings and reduced individual equipment. The distributed equipment option is closest to the conventional approach, with a full kitchen in every unit, although perhaps using automated and modular elements. We think the level of centralization and automation for this function will be a strong personal choice, and should allow flexibility in design to accommodate it.


F.2.1.1.2.4 Maintain Health Data

This section includes data for the Maintain Health function within Habitation. Supply of residents and visitors is an input to this function, and a percentage of human time for labor is an output. Eventually this function must account for demographic changes among the residents, and flow of visitors and guests, but at first we can use static averages. The tasks include supporting basic needs for sleep, sanitation, exercise, cleaning of persons and the environment, and filtering the latter, health monitoring, first aid and emergency services, and local examination and treatment.

Maintain Health Requirements

We can allocate a large percentage of Habitation risk reduction to this function by providing exercise, cleaning and filtering, and local health monitoring and services. At best we can make such features available, but we cannot force people to use them.

Maintain Health Alternatives

The Earth's surface is full of living things that tend to spread to any unoccupied location, including living spaces. This includes items like insects, mold, and even larger animals. Aside from regular cleaning of interior space, periodic inspection and cleaning of less used spaces like ducts, attics, and crawl spaces should be planned for, and exterior cleaning of buildings and the surroundings. Less accessible spaces like wall interiors need to kept dry and clean by design to prevent growth and infestation, and preferably include a way to access them for inspection at longer intervals.


F.2.1.1.2.5 Personal Items Data

This section includes data for the Provide Personal Items function within Habitation. It includes the internal volume for private living and storage space, and community space such as meeting rooms, athletic areas, etc. It also includes contents of this space such as furniture, decorations, and non-protective clothing. The total living space then becomes a design requirement for the Protect and Control Environment functions.

Personal Items Requirements

In addition to the nominal occupied capacity of 75 people per year and 660 total, we allow an additional capacity of 5 per year and 40 total of vacant space to account for people in transit, remodeling, guests, and other reasons for space not being actively occupied. Corresponding land allocation is also required.

Personal Items Alternatives

Part of the Habitation space is assumed to be used during prior phases and construction as temporary offices and storage. As permanent facilities get built, these get moved to permanent site operations and storage spaces.


F.2.1.1.2.6 Information System Data

This section includes data about the Provide Information function within Habitation. Modern computers and networks are very capable and flexible, so we expect to share the same systems across the location for communications (text, voice, and video), education, entertainment, and general information like news and weather. The same systems are also assumed to be shared for internal location design, production control, internal transport, remote location operations, and outside work where possible. IT systems are rapidly changing, so flexibility to update all the system elements should be planned for. For instance, cabling should be installed with room to pull additional lines or replace existing ones without having to dig up the landscape.

We do not expect to design and build our own information system components. Those items are mass produced, relatively inexpensive, and highly specialized. Where we expect to innovate is in how they are integrated by design into a location and community, their physical installation, and custom software for tasks not normally carried out electronically.

Information System Requirements

There is not a higher level requirement for information passed down to Habitation. Instead, we derive information needs from the goals of Autonomy and Self Production (2.3), a high Quality of Life (2.4), and low Location Risk (6.1). The ability to control and perform most tasks locally leads to a need to communicate outside the location, for example to order food supplies that cannot be grown locally, or do office jobs for outside customers from home. Our concept of a high quality of life includes ample contact with other people, access to education, and entertainment. Lowering location risk includes physical design for safety, such as strength and fire resistance of construction, but also active monitoring and response to hazards, which has an information component.

Information System Alternatives

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