MHS Framing and Mold Infestation

In recent years, mold infestation has emerged as one of the most insidious threats to the home - and one the building and insurance industries have had a very great difficulty addressing. Mold infestation is a very serious health hazard and homes which succumb to it become totally uninhabitable even though structurally in perfect condition. Mold infestation is the direct result of the common choice of materials and building practices applied to wood frame housing. It is a product of an obsession with cheap polymer based composite materials and high thermal efficiency. Mold infestation occurs when laminate materials such as wallboard, plywood, chip-board, and oriented strand board (OSB) become host to molds in the interstitial spaces between laminate layers. Molds feed on the glues and cellulose which bind many composite materials together, this becoming a particularly favorable environment for them when combined with trapped humidity as a result of using plastic 'house wrap' products, sprayed foam insulation, and polymer paints.

Once one wall in a home is 'infected' by mold it will freely spread from one piece of plywood, OSB, or wall board to another wherever they come in contact with each other, quickly taking over an entire home! There is NO effective means of abatement for this. Once a wood frame structure is sufficiently infested with mold, the only solution is complete demolition and incineration of the house! No surprise, builders and insurance companies have become very reluctant to address this problem because of the huge costs this represents - not only in terms of home losses, but also in terms of medical expenses for residents over an extended period of time.

Conventional wood frame construction offers no defense against mold infestation other than seeking to carefully manage humidity levels during construction.

Homes that retain the 'breath ability' common to earlier forms of construction are rarely prone to mold growth, but virtually no builders in the US have such skills anymore. Therefore, this problem is anticipated to get progressively worse during the coming years. When using OSB-based SIPs and conventional wallboard products, MHS is still prone to this hazard. However, it has two very important forms of defense that wood frame construction lacks: 1. MHS aluminum frame members function like a fire-stop to the spread of mold between walls, and 2. the ease of replacing infested wall sections without great difficulty or expense. Even in the event of massive contamination, the aluminum structure of the MHS home is itself unable to harbor mold and so is always recoverable.
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Termites and MHS aluminum structure

By virtue of its metal composition, MHS is naturally immune to damage from termites, carpenter ants, and other wood damaging pests. MHS also offers other benefits with regard to pest resistance. The hollow wall cavity structure of conventional wood frame structures is often prone to pest infestation because the hollow spaces hidden behind wall board, plywood, and other cladding present a virtual highway by which animals can move freely through the unseen structure of a home. Many forms of insulation also provide pests with nesting material. The conventional approach to resisting pest infestation has been to apply chemicals such as pesticides and formaldehyde to insulation and lumber products in order to either kill pests when they enter a structure or make the structure uninhabitable to them. However, this also tends to make these products latently toxic with potential health threats to human inhabitants. By using SIP wall panels, MHS resists pest infestation by employing a more monolithic structure.

SIPs are not entirely pest-proof - unless they are of the metal clad type - but the continuous foam fill eliminates the spaces that pests can exploit while the surrounding frame structure presents an impassible barrier between sections of structure.

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Moisture and MHS aluminum frame

The installation of Structurally Insulated Panels as a wall, roof, and floor is often subject to swelling by moisture. The result is often an uneven wall, roof, or floor. MHS Technology insets the SIP in the aluminum extrusion and then connects with other extrusions to create a space frame structure. This releases the previous function of the SIP as a structural element into just a surface occupier.
In a MHS aluminum frame the patented design of the extrusion allows the inset of panels. Environmental concerns and limitations can be adapted to the surface of a structure (SIP, brick, adobe, glass, others in architectural manual) without placing a heavy responsibility on the space frame module of MHS.
In the event, that moisture penetrates the tiniest openings of the border outlining the extrusions and SIP then that wetness is absorbed by the inset OSB. This tightens the space within the extrusion outline and border of the space frame. The proportion achieved by arranging the extrusions in a modular placement thwarts the capability for the connection to dismember internally from the pressure of its inset surface material. A rigid MHS frame after exposure to moisture along its extrusion outline becomes pure and ripe in rigidity as the structure systematically bonds.
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MHS Challenges Natural Disasters-Hurricanes

Perhaps the most powerful of all meteorological forces on the Earth, hurricanes are a steadily increasing threat as larger and larger populations move to coastal regions. Hurricanes mainly present three basic sources of damage to the home; wind, waves, and flooding from storm surges. But one of the added problems with hurricanes is that as they destroy homes the debris created by this destruction becomes projectiles that increase the hazard to other homes. Thus poor quality homes are not just a hazard to themselves; they are hazards to whole communities. This fact has compelled many coastal communities to impose very stringent building codes intended to insure a minimum standard of hurricane resistance for all structures.

Stick frame homes are prone to wind damage from hurricanes for the same reasons they are prone to earthquake damage; nails have a hard time holding things together if they shake or vibrate. Roofing is particularly prone to this problem in response to wind and is one of the greatest sources of debris, commonly being the first part of a house to give-way. The common method of reinforcing homes against hurricane winds is similar to that employed in increasing earthquake resistance -since the root cause of weakness is the same.

Key portions of the structure like the roof are reinforced by adding strapping and gusset plates which are mounted-sometimes- with bolted connections.
In addition, roofing panels may use bolted or screwed attachment rather than nails or may have additional steel strapping, adhesives or adhesive membranes may be added to reduce the tendency of roof shingles to fly off, special kinds of shingles made in continuous strips or with proprietary locking systems may be used, or-perhaps best of all- metal panel roofing with bolted connections may replace conventional roofing altogether.
Here MHS offers the same advantages it offers in respect to earthquake resistance. With positive interface between all components, it simply isn't as likely to come apart under the vibrations induced by wind as nailed construction.
Similarly, with its wall panels held in place continuously along their perimeter they are far less likely to come off and become projectiles, though any nailed siding applied to wall panels is just as likely to come off as on a stick frame structure.
A secondary form of wind damage is impact damage resulting from flying debris. With such extremely high wind speeds, debris impacts the structure of homes with extreme force causing great damage. Penetrations of the walls or roof often lead to subsequent failure of the structure, thus expanding the field of debris.

Stick frame construction has long tended to perform poorly in resistance to such debris impact and much research has gone into trying to find means of reinforcing the wall and roof cladding materials. The use of Structural Insulated Panels for walls has fared well in this respect. SIPs are more monolithic in composition than stud framed wall structure and impacts produce less secondary debris, passing through the SIP like bullets but not causing the SIP panel to come apart whole.
Since it also relies on the use of these, MHS offers the same advantages but improves on this by virtue of the fact that its SIPs have a much more secure and continuous perimeter interface to its overall structure. So while the SIPs of a conventional SIP based or hybrid SIP and stick frame home have the potential to be shaken apart along their nailed connections, a SIP used for walls in an MHS structure could sustain massive amounts of damage before finally coming free.
And when it does, the aluminum post and beam structure itself will remain largely unscathed, whereas the stick frame or SIP based home could be prone to structural failure.

Wave damage is primarily a problem for the few homes that are in direct proximity to the shore. There damage is caused primarily by the subsidence of foundations caused by waves washing sand and earth away or direct damage to home sub-structure by wave impact. Immersion also tends to deteriorate the wood in this structure, making it progressively weaker over time. Considering the environment such sub-structure is subjected to, nailed construction has long ago been abandoned even for structures which are otherwise of conventional stick frame construction. Here MHS is on a roughly equal footing to the conventional structure except that its aluminum composition is immune to the effects of water and thus will not deteriorate over time. However, the elevated substructures used for coastal homes are often based on very large scale timber components. MHS may not be able to approximate this without some kind of compound strut structure or by employing a hybrid of other larger scale aluminum I beam structure. Storm surge damage is essentially the same issue as with flooding and MHS relates to stick frame construction in the same way as noted above.

MHS Challenges Natural Disasters- Flood

While occasional extreme flood events can destroy homes outright, the most common danger posed by flooding is the damage to structure and finish materials as a result of immersion in water. Most floods do not completely destroy the structures of homes. Instead, they immerse a portion of the home and do damage through the subsidence caused by the washing away of soil around foundations. But the effect of water on the materials commonly used in wooden stick frame homes is devastating to livability even f they retain most structural function. Stains and odors become permanently mbedded into them, they become warped or delaminated, fungus ontamination permeates all cellulose materials. The result is that, post flood, he typical home must undergo extensive and expensive renovation and ometimes homes that are otherwise structurally sound become so costly to enovate that they are simply abandoned or deMHS offers many advantages in the event of flood damage. The aluminum omposition of the structure is completely immune to the effects of immersion, hough subsidence of foundations is still a serious threat. Wall panels may be as usceptible to immersion damage as conventional stick frame walls but they are ar easier to replace than stick frame walls by virtue of their modular construction.

Also, just as they create a fire stop for the spread of fire in wall panels, the luminum frame components also present a kind of fire stop to the spread of ungus contamination, since the spread of fungus in wall panels materials occurs here there is communication by layers of cellulose material. But there is perhaps ne virtue of MHS which surpasses all others. MHS allows one to readily and apidly move a whole home out of harms way. If one is faced with an impeding lood event that offers some time before a home is immersed, one can literally ake it all apart, pack it up, and ship to high ground! This virtue also eliminates the eluctance many people stuck in flood prone areas have toward relocation. hile we have a highly mobile society, this mobility is contingent on the ungibility of the home, not its direct mobility. A home in a flood prone zone loses ts resale value and, therefore, the mobility of the home owners is lost. With MHS here is no loss in equity in the home if it is forced to move because it is emountable. This is one of the most powerful of all virtues of modular building echnology.molished whole.
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MHS Challenges Natural Disasters- Fire

Fire

In comparison to wooden frame construction, MHS offers few advantage in terms of fire resistance. Its aluminum frame structure is not flammable but it's also not immune to the damage of fire. Aluminum profiles will fail by metal softening at longer times than lumber will. MHS used structural aluminum alloy 6061-T6
And its wall and roof panel materials may be roughly the same in fire resistance as stick frame walls. How ever company interoduced a new Flameproof Sandwich Insulated Panels (FSIP) to used with MHS building System. MHS offers one great advantage is in fire containment. The aluminum post and beam structure effectively isolates the more flammable materials of wall panels like a network of fire-stops or fire walls. Thus the time fires take to spread may take longer. Its standardization on the use of metal exterior cladding is also an advantage in resisting fires from external sources.

Another great advantage of MHS is seen after a fire event, assuming a home has suffered only partial fire damage. Most of the materials used in the conventional stick frame home will retain residue of smoke and toxic chemicals from burned plastics indefinitely. They will also suffer extensive damage from the water and fire retardant chemicals applied in fighting a fire. Thus even small brief fires can require extensive renovation to completely restore the livability of a home. In contrast, being composed of aluminum, MHS's frame material will not retain any residue of fires and is completely undamaged by wet or fire fighting chemicals. It's quick modular construction makes recovery from a fire quick and simple.

MHS Challenges Natural Disasters- Earthquakes

By : Eric Hunting
Part 2

Under the forces of an earthquake a building's structure is deformed mostly by strong horizontal movements which create great shearing forces on its joints. The framing 'wracks', pulling back and forth, square frames pulled into rhombus shapes with alternating joints pulled out and in. For nailed joints the effect is akin to having someone rapidly flexing the joined pieces of wood with great force or wedging a crow-bar between them. This loosens the nails by pulling them back and forth, widening the split between the fibers that was first made when the nail was driven into the wood and weakening the connection. Such structures usually fail in an earthquake at the nail points, the wood finally splitting and cracking apart as nails are twisted or the nails being pulled out. After an earthquake home owners are often frustrated when authorities will not allow them back into their homes to recover their goods even when the buildings, from the outside, don't look too damaged. But the emergency workers know that all the nailed joints in the structure may be greatly weakened, with perhaps many cracks being hidden behind the cladding of the home, ready to fail at the least vibration or live load.
Mobile homes are a little better in the face of this sort of damage in part because they are normally no more than a single story high. This reduces the top mass of the structure greatly and hence the amount of shearing force applied as the structure shakes. They are also engineered to tolerate the conditions of road transport so they tend to be made to resist wracking better. But it's largely because of one of their great weaknesses; their primitive foundations. Most mobile homes have no more foundation than a set of little metal pyramid piers which stand on plastic or cement pads on the ground. When an earthquake hits these are quickly broken away, the structure then being free to slide around on the ground as the earth shakes under it. Unfortunately, in the process the underside and lower edges of the structure-not to mention any trailer wheels- can be quite torn up and then the single greatest flaw of mobile homes -their very poor repair ability comes into play to doom a structure nature itself didn't completely destroy.The standard techniques for reinforcing stick frame structures against earthquake damage involves control of wracking and hence the deformation caused by shearing forces. This is usually done by bracing the corners of frames with various forms of 'gussets' or adding diagonal tension members across frames to tie opposing corners.
These components are typically made of steel and are often bolted in place rather than being nailed in place. Diagonal bracing was common with the balloon framing of the late 19th century but disappeared as lumber shortages compelled builders to rely on shorter length timber.
Old Japan homes commonly employed post & beam construction with nail-less joinery. This had many advantages in that earthquake prone region. Nail-less joinery typically relies on a 'positive' or 'compression' interface between wooden components.
Thus one of the stronger properties of the wood -it's compression strength perpendicular to its grain- hold structures together and is doing the work of resisting shearing forces in response to the shaking of an earthquake. Joinery in the traditional Japanese home was often deliberately left a little 'loose', allowing the structure to be more flexible in response to earthquake shaking. This allows the full resilience of wood to come into play, structures flexing greatly but in the end withstanding the abuse. No surprise that this form of construction was employed through most of Japan's history. Let's now consider the way MHS behaves in an earthquake. Like nail-less post & beam structures made of wood, MHS relies on a positive interface between its components. All its components are bolted or clamped together. Thus it should exhibit the same resilient characteristics of the wooden structure and nail-less joinery with the benefit of the increased tensile strength of metals. Like the old style Japanese house, the MHS house will flex greatly but in the end it will return to its original shape.

However, MHS's aluminum profiles and clamped joint connectors are more rigid than wood and would not bend to as great a degree as wood will without suffering permanent deformation. But at the same time it is going to resist -due to its tensile strength- that high degree of bending better than wood can and so may subject its joints to less shearing force. In essence, MHS should behave more like the steel frames of skyscrapers which, as is well known, is one of the safest forms of structure in an earthquake. Where MHS may actually do more poorly than wood is in conditions of constant vibration or extremely frequent tremors. Aluminum is subject to a greater potential for metal fatigue because its molecular structure tends to retain deformation.
This metal fatigue will eventually lead to cracking of the components which cracks occurring at connection points. But these are conditions more typical of a vehicle suffering the vibration from decades of constant use. That is unlikely for any stationary structure.
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MHS Challenges Natural Disasters- Earthquakes

By : Eric Hunting
Part 1

Perhaps the most destructive of nature's hazards, earthquakes havewreaked havoc on human habitation since the dawn of civilization and, while no form of construction can be considered truly immune to damage from this powerful force, in the most earthquake prone regions many different methods of coping with it have evolved. In general there are three ways structures can be made to withstand the forces of earthquakes; resistance, resilience, and dynamic response. Resistance basically means making a structure so physically strong and massive that it resists the damage the shock forces of an earthquake produce. This approach has tended to be difficult to employ because it often calls for large volumes of material. When the limit of resistance is reached, it may mean total and sudden structural failure, in which case the massive amount of collapsing material itself becomes the chief hazard. Underground homes have been the most successful with the strategy of resistance because their subsurface location allows the structure to communicate the shock waves of an earthquake like the earth around it rather than simply withstanding them by brute strength. This makes them some of the most earthquake resistant structures of all.

Resilience means the ability of a structure to suffer physical deformation in response to shock forces and return to its previous state with little or no damage.
Historically, this has been the most successful approach for building in earthquake prone areas. Japan is infamous for its frequent earthquake activity and its traditional approach to dealing with this hazard for housing was to rely on relatively light post & beam wooden construction which could be shaken violently but return to its previous state with little damage. If structures did fail, light composition meant there was less potential injury from falling material and often the structures would not fail completely, leaving opportunity for refuge and escape. Post & beam construction also offered the advantage of relatively quick repair after an earthquake, the nail-less joinery leaving surviving materials and components intact for reuse. This approach is also the approach common to steel framed skyscrapers and is responsible for the adage that skyscrapers arefar safer than other structures during an earthquake.
Dynamic Response is the high tech strategy for dealing with earthquakes. It is based on designing systems of components which allow a structure to respond dynamically to the forces of an earthquake. This may take the form of springs of cushions in a system of foundation piers. Or it might take the form of special limited motion sliding plates that allow the earth to slip under the structure as shock waves pass through it rather than transmit them to the structure. Another approach is to mount systems of mass dampers or shock absorbers in different locations in the structure so that it dissipates the energy of shock waves passing through it. The cost, sophistication, and perpetual maintenance overhead of these systems tends to limit their use to the largest and most critical of buildings.
Conventional stick frame homes and prefab mobile homes rely on the strategy of resilience for tolerating earthquakes and their predominantly lumber composition works fairly well in this respect. Natural lumber is a very resilient material. Their limitation is the use of nailed joints. Wood is exceptionally strong except in one respect; under tension force in the direction perpendicular to its grain. Wood is essentially a fiber material. It's like a very stiff rope made up of individual strands of fiber. Pull the rope in a direction parallel to the direction of the fibers and it is very strong. But pull a rope sideways, perpendicular to the direction of the fibers, and the individual fibers readily come apart and the rope unravels.
This is why pieces of wood will sometimes split when you drive a nail into them. A nail pushes between the fibers of the wood, breaking their weak adjacent bonds, and if it's a particularly hard or thin piece of wood -or the nail is very thick-has a potential to split the wood, generating a crack that spreads in parallel to the grain. This is why homes tend to be made with softer woods like pine, the softer wood easily crushed under the point-compression of a nail and so offering less resistance to the penetration of nails and cracking less frequently. The friction between the nail and the wood along the surface area of the nail is what holds nailed connections together. The strength of this connection is generally determined by the length of the nail and thickness of wood, which increases the surface area of the nail in contact by the wood. This is generally a fairly strong connection but it’s a connection that relies on the weakest aspect of the wood; the bond between its fibers. Once broken, the bond is never restored and the wood is permanently damaged. This is why one can't re-use a nail hole. And this is also why it takes many nails spaced out over a large area to effect a very secure joint.
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MHS Challenges Natural Disasters

With extreme weather increasingly frequent due to the effects of Global Warming, news of various disasters supplied steadily from around the globe, and home insurance companies increasingly reluctant to meet claims or provide insurance in the first place, there has been growing concern about the ability of homes to withstand nature's fury. The Modular Housing System from USS offers a number of advantages with hazard and disaster resistance compared to conventional building methods. We will look at how MHS compares against conventional stick frame construction and prefabricated mobile housing in the face of different hazards.
One of the common mistakes made by designers when addressing the issue of disasters and hazards is to focus exclusively on withstanding the effects of nature without damage.
But in any arms race between man and nature, nature usually wins. So it's just as important to think about how a structure recovers from damage, how a building is repaired and its materials salvaged in order to ameliorate the inconvenience and financial losses from a disaster. As we will see, this is one area where MHS excels compared to all other structural systems.
continue.....

MHS offers some degree of superiority over stick frame construction

By : Eric Hunting
Part 4
MHS solves the wall fabrication issue using SIPs and other panel materials which slide into the paired grooves of the frame profiles. This affords the ready demountability of the Japanese light partition panels while allowing the use of more resilient materials like sheet metal or ceramic with weatherproof gasketing along the exterior faces. The result is a hollow wall system like that of stud frame construction, able to accommodate insulation, utilities runs, and built-in fixtures but with none of the disadvantages of stud frame construction. This also allows for the use of pre-finished materials or materials that need no finishing, since the walls are mechanically fastened. One can use virtually anything one might want for a wall surface; conventional plaster coated sheet rock, solid wood planking, veneer board, metals, cloth, plastic, Panelized masonry materials (gypsum plank, ferro-cement panel, corrugated clay panel), or just about anything else one could imagine. The MHS frame will even serve adequately as a window frame allowing for the direct integration of window panels.

And if this isn't powerful enough, this method of panel integration offers the option to physically integrate whole pieces of furniture or appliances fashioned into this panel shape. Photovoltaic and thermal solar panels, flat panel TVs and home entertainment systems, computer systems, plumbing fixtures, lighting fixtures, HVAC systems, shelves and cabinets, 'Murphy' beds and folding tables, art objects, and more can all be designed to integrate directly into this frame system just like the many industrial components which integrate with T-slot framing systems. To facilitate this kind of integration, the MHS profiles will also integrate with a smaller scale version of the same kind of profile originally developed by US Systems for store display framing. This system can be used to fashion many kinds of furniture and appliance enclosures and will plug right into the larger MHS frame structures. This capability to integrate so many kinds of materials and equipment creates the potential for a vast third-party marketplace of products to plug-into MHS housing -much like the innumerable peripherals and software which are made for personal computers.

At present one feature of MHS limits the flexibility inherent in the rest of its building system, and it's something which also troubled builders in pre-industrial times. The one thing it cannot, at this time, realize with the same modularity and demountability as the rest of its system is its roofing. This is because we have yet to realize a fully weatherproof roofing system which can be freely changed in area using modular remountable units.
There are two sides to this problem which tend to work against each other. On the one side is roof cladding -the material which makes the roof waterproof. Modular roofing materials exist in the form of shingles and tiles. Though uncommon in shingles, tiles are readily remountable and reusable and so one could use them to fashion a modular roofing system that can be changed on demand to suit changing roof areas. But tiles and shingles only work with a sloped roof. They rely on the force of gravity to insure that water sheds off them in one direction. On the other side we have roof shape. Sloped roofs are difficult to modularize because as you increase the area under a roof you must simultaneously increase the length of the rafters and beams supporting the roof. The flat roof solves this problem. Its rafters remain the same length no matter how you increase the area. You just add more of them. But roofing tiles won't work for a flat roof! Most flat roof construction relies on some form of monolithic material; membranes of plastic or asphalt sometimes called 'composite' roofing or layers of continuous concrete.

The closest we can come to a solution is a set of compromises. One can make modular sloped roof units and repeat them as the area of the structure increases. This way the individual roof structures don't have to be changed. One just adds on more of them for the newly added sections. But there are practical limits to this. Roofs valleys -the points where opposing descending roof slopes meet in the center- tend to be leak-prone and can get complicated if you try to mix roof sections of different sizes. The other option is to use a flat roof and a kind of roof panel which is modular in one direction and monolithic in other. Raised seam metal roofing is the prime example of this. This kind of roofing consists of long panels of sheet metal -or sandwiches of sheet metal and foam insulation- which are joined along their sides by raised seams. Water sheds off the panels only in parallel to their seams, since they create a channel. It's as if you made a roof tile that was very long and overlapped on its sides. Such roofing is readily expandable in the direction perpendicular to its seams. But it can't expand in the direction parallel to its seams unless -just like the old fashioned roof tiles- there's a slope in the roof that allows them to overlap. Of course, this is just as much a problem for stud frame structures as for post and beam structures. We just don't have, as yet, a roofing technology that lets us freely expand a roof in all directions while using modular parts. But a solution may come if people finally clue-in to the virtue of plug-in architecture and start applying some modern engineering to it. For the time being, MHS offers the option to use either of these compromise approaches, or one can just settle for a more conventional sloped or flat roof in shingle, tile, metal panel, or composite.
In conclusion, we can see that with MHS we have a building system vastly superior to the stud frame construction common to contemporary housing. It restores and greatly improves upon the virtues of the traditional post and beam construction system and so simplifies the process of construction that it becomes quite practical for most anyone to assemble their home on demand in a very short time. It has the potential to be a true plug-in architecture that anyone can use -and not just for housing but for an infinite diversity of applications. With a modular structural system offering ready demountability we not only have infinite flexibility but indefinite repairability and the option of transportability. Not only can the home be eternal, we can pack it ALL up and take it with us wherever we go! We don't have to go into great debt to buy more house than we need in anticipation of what we might need in the future. We can change our house to meet our needs on demand. And with the freedom to take our whole home with us when we move just like it was a piece of furniture we don't need the crutch of bank financing to make the value of our home fungible. And we don't have to fear losing the value of our home investment if there are differences in market values one place to another. We can think about things like saving for a home by literally stockpiling its parts or letting our children take a portion of the family home away with them when they are old enough to leave and live on their own. With a healthy industry based on this kind of building technology in place, we can also expect the appearance of a large after-market for used components. This would be a practical solution to the problem of low-income housing and possibly an answer to the problem of hopelessness as well -though, of course, having a place to build a home is just as important as having the stuff to build it out of.

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