Hundreds of papers and reports have been written over the past five decades regarding negative health effects of electromagnetic fields, but much work remains to be done. One important topic where relatively little research has been done is that of safe and healthy housing. We are surrounded by a toxic soup of electromagnetic fields, so one focus of the Healthy Housing Research Institute (HHRI) will be to investigate methods of reducing the interior fields inside a house. If the house construction reflects or absorbs most of the exterior fields, then those with Electromagnetic HyperSensitivity (EHS) can heal while inside the house. Those with mild EHS might still be able to work at a regular job, if they can just get a decent night's sleep.
Anyone who has ever built a house is painfully aware of the hundreds of decisions that must be made. Many involve research into competing alternatives. For example: Should it be adobe, straw bale, Insulated Concrete Forms, or stick built? We read literature, watch videos, compare prices, and make an informed decision. The same is true for any house built by the HHRI, where we must rely on other people's original research. In some cases, however, we must do the original research ourselves. The following is a list of research areas and tentative decisions made for the HHRI first experimental house. Actually, it is the size of a small house but does not have a kitchen or bathroom. It was permitted as a shop/office/lab. I will refer to it as a shop in the following.
I selected Morton Buildings as the contractor for the shell of the shop. They are in operation nation wide, in business since 1906. They sent in an experienced crew with a truckload of posts, trusses, and pre-cut panels. The selected size was 1440 sq. ft. (30' by 48'), ranch style (single story, no stairs), slab on grade, metal roof, metal siding on outside, metal ceiling, and metal interior wall covering on the exterior walls of the building. When Morton was finished, the shop looked like a complete house from the outside, with all doors and windows in place. The inside, however, was totally bare and empty (except for a small storeroom in one corner of the shop). Only the exterior walls are load bearing so there are no posts or columns inside. I hired a local contractor to install the concrete slab and an electrical company in Pueblo to do the wiring.
The wall surface needs to reflect as much of the incoming toxic electromagnetic soup as possible. This immediately suggests using metal siding, which has been used for agricultural buildings for many decades and is not uncommon for house siding. It is fire resistant, an important consideration for houses built in a juniper 'forest'. Good quality siding is also hail resistant. It is claimed that the painted finish will last at least 50 years. Several agricultural building manufacturers have adapted their metal roof, metal siding buildings for the housing market, so this type of construction is readily available at reasonable costs. Standard metal skin housing leaks EM signals through all the windows, doors, cracks, and seams, so the research activity will be finding the best methods to reduce these leaks.
Standard Wisdom states that a Faraday Cage needs to be well grounded to a local ground (not the noisy ground provided by the utility company). The shop has its own 100 Amp circuit breaker box, which also needs to be connected to this local ground. There are two methods of obtaining a local ground. One is to drive one (or more) ground rods vertically down into the earth. These are copper covered steel rods, perhaps 10 feet in length. The other method is to connect to the rebar used in the concrete slab and foundation, called the Ufer ground. This method requires ground currents to flow through the concrete to the earth below the foundation. Concrete is not a particularly good conductor, but a very large cross-sectional area of concrete against earth gets the resistance down to an acceptable level. In this high desert environment the water table is more than 100 feet down. A ground rod in totally dry earth has a very high resistance to ground, and is basically useless for grounding purposes. The earth under a foundation, on the other hand, will always have some moisture in it, making the Ufer ground the preferred grounding method. A section of rebar was bent with the horizontal portion attached to the slab rebar structure with stainless steel hose clamps and the vertical portion 'daylighted' through the concrete for attachment purposes. This was done at the circuit breaker box location, for code purposes, and also elsewhere for grounding the steel panels.
Before Morton installed the interior steel panels, I stapled a strip of copper foil onto the top nailer, above the windows and doors, and connected the foil to the Ufer ground. Morton then installed the vertical steel panels with several screws through the foil into the wood nailer. Each steel wall panel is then electrically connected to earth, both directly by the metal screws and also by capacitive coupling between the panels and the foil. The 60 Hz wiring is behind the panels so the 60 Hz electric fields inside the shop should be negligible.
I did not put copper foil on the bottom of the trusses, nor on top of some of the roof nailers. That would have required me to spend significant time going up and down ladders, which I religiously avoid at my age. That means that the ceiling and roof panels were not especially well grounded. The paint on the panels would insulate adjacent panels from each other, at least for low voltages. Screws are placed through the panels where they overlap, forming a relatively high impedance short between panels. It is quite safe as far as the National Electrical Code (NEC) is concerned. But the measured impedance between a ceiling or roof panel to earth could be as much as a few ohms, as compared with a fraction of an ohm for the wall panels with copper foil behind them.
This leads to an interesting situation where a legalistic application of the NEC results in something unhealthy for the EHS person. Some readers will have heard of 'ground loops'. In setting up a nice audio system, it is important that each component be grounded at one point only. If components are connected to earth at more than one point, there are parallel paths for ground current to flow. Any time changing magnetic field will induce a voltage in this loop, which will cause a current to flow. This current produces its own magnetic field, which in turn produces noise and distortion in any audio output. I suspect every audiophile has had the experience of trying to find the unnecessary ground point in an effort to reduce noise. It may come as a surprise, but the NEC requires ground loops. Consider a single-phase power distribution line running down the alley behind your house. There are two conductors, one at several thousand volts and the other (called the neutral) very close to earth voltage. A copper wire runs down each pole, connecting the neutral to earth. Neutral current flows partly in the neutral conductor and partly through the earth, according to the relative impedances of the two parallel paths. The earth current increases the 60 Hz magnetic field we experience, even miles away from the power line.
Inside a house, the NEC officially follows the 'no ground loop' policy. Each wall receptacle has three conductors, hot, neutral, and ground. The ground wire is connected to the metal mount of the receptacle. If a metal box is used, as is the case for my shop, screwing the receptacle to the box makes the box also connected to ground. As the metal panels touch the boxes, parallel paths for current flow are established, one path through the panels and the other through the ground wire that connects the boxes together. The intent is that no current flows on the ground wire except during electrical fault conditions. While this is the case, there is no 60 Hz magnetic field produced, and everybody is happy. However, if the electrical cable between boxes has any twist or spiral, current flow in the hot and neutral wires will induce a voltage in the ground wire, which in turn will drive a current through the panels touching the boxes. There is now a magnetic field produced that would not be present if sheetrock (a fairly good insulator) was used instead of steel panels.
The shop has two circuits for ceiling lights, each with 11 light fixtures. One circuit has incandescent bulbs, the other has LED bulbs. The hot and neutral conductors for the incandescent circuit carry about 5.5 Amps at the start, dwindling as one approaches the far end, and the LED circuit starts with about a fourth as much current. The currents in the hot and neutral conductors each produce a significant magnetic field, but because the two currents are close together in space and opposite in direction, the net magnetic field produced is very low. I was surprised to see a magnetic field of almost 3 milliGauss (mG) waist high in the middle of the room. I went through and unhooked the ground wire from each ceiling box. (The ground wire is actually redundant for safety purposes, since the steel panels serve the same purpose.) When I lifted the ground wire from the next to the last box, the magnetic field dropped abruptly to below 0.1 mG. This occurred on both circuits. For test purposes I had put some high wattage bulbs at the end of the LED circuit. I am confident that both circuits were wired according to the NEC.
One possible fix to this problem would be to use plastic boxes rather than metal boxes. Plastic boxes are perfectly legal for wall receptacle purposes. There may be a strength issue for ceiling light fixtures where possibly heavy fixtures need to be supported by the box. If you are intolerant to 60 Hz magnetic fields at the few mG level, you will want to raise this issue with your electrician and the electrical inspector before building this sort of house.
WINDOWS AND DOORSThe Morton windows came with plastic screens that covered one of the two glass panels of the window (when closed). I removed the plastic and replaced it with aluminum screen from Home Depot. This provides no shielding for the remaining portion of the window so a second screen, also aluminum, was added to cover the entire window. It would probably be better to use stainless steel or copper screen, but I want to test what is readily available first.
I specified steel doors from Morton, but did not think about the door frames, which are typically wood (or maybe plastic). Wood frames meant there was about a one inch gap between the steel door and the steel panels which is essentially transparent to cell phone signals. Replacing a door assembly with the metal frame style is a non trivial task, so I decided to leave the existing doors and just build a screen door. This screen door has to be wider than the 3 ft walk door to cover the gap of the wood frame. I bought some 8 inch cedar boards and built a 4 foot wide screen door. The unstained cedar is similar in color to the tan steel panels of the shop.
BUILDING ENTRY LOSSA major motivation for building with this particular technology is the hope that it will reduce the interior fields substantially, to the point that the electrically sensitive can get a good nights sleep inside such a building. That means that we need to measure the fields both internally and externally so we can properly compare different techniques. The difference between the external and internal fields is called the Building Entry Loss (BEL). The BEL has been of interest to cell service providers for decades. Results of many measurement programs are available on the Internet. A relatively new way of measuring BEL is to use a Smart Phone with an app that displays the local signal strength. This would seem to be a good way to measure BEL. Anyone who can borrow a cell phone can make measurements whenever convenient, without buying additional equipment. My cell phone showed a BEL of perhaps 8 to 10 dB for my home in Canon City, perhaps 10 to 12 dB for the house in Rockvale, and about 25 dB for the shop. A lengthy discussion of my findings are presented in BuildingAttenuation.pdf.
Some external fields will leak into the interior of the house in spite of our best efforts to prevent this from happening. There is also the possibility of the house wiring, lighting, and computers producing unwanted fields inside the house. A signal source inside a metal box can set up what is called a standing wave pattern, where there will be 'hot spots' of much higher field strength than would be seen if the source were outside in open air. For this reason, it appears essential to place a good absorbing material throughout the house. The best material is water. Its absorbing properties enable microwave ovens to work. Interior walls made of stacked containers of water (like five gallon buckets) would soak up any stray fields very nicely. Five gallon buckets are unattractive, take up an excessive amount of floor space, and have other disadvantages as interior walls, so are unlikely to actually be used in housing for the electrically sensitive. I tried a 'Quick and Dirty' test to see if the benefit was significant enough to justify a more extensive test. This consisted of a row of five gallon buckets, seven wide and two high. I measured the interior fields with and without the buckets. Results were not impressive! Certainly far from adequate to justify more extensive testing. It still seems like a good idea. Perhaps some good idea will present itself about putting water in leakproof containers inside the interior walls.
We will also test the use of steel mill slag as an absorbing material. It is readily available as road base from a steel plant in Pueblo. It can be used either loose or as aggregate in concrete. As mentioned, the shop was completely open inside when Morton finished, except for a small storage room in one corner. It needed some interior rooms to at least partly resemble a house. These rooms could be used as office space when all testing was completed. I decided to build two office/tack/bed rooms in the south end myself, rather than hire a contractor. I set up a old radial arm saw in the middle of the shop, and had Ace Hardware deliver a truckload of lumber to the site. The concept was to build a conventional 2" by 4" stud wall on 16" centers, and fill the empty space between studs with slag. The most common wall covering is sheetrock, of course, but I decided to use tongue and grove knotty aspen wood instead. One reason is that most sheetrock contains recycled cardboard, which usually got wet and moldy during the collection cycle. This mold could damage some of the very chemically sensitive. Another reason is that I was concerned about the strength of the sheetrock, whether it would be able to withstand the outward pressure of the loose slag. A third reason is that using knotty aspen allowed me to have a building with very few man made chemicals in it. There is a bare concrete floor, outside walls and ceiling covered with powder coated steel siding, and inside walls covered with bare wood, no paint or polyurethane.
There is a wall about 28' long with two doors that is crosswise the building, and another wall about 12' long that separates the two rooms. The 12' wall was finished to the ceiling and left empty. The 28' wall was finished to the ceiling on one side and to a level just above the doors on the other side. A helper carried in buckets of slag and dumped them into the wall cavities. About 5000 pounds of slag was spaced into about 23 linear feet of wall. The remaining uncovered studs were covered with knotty aspen to the ceiling. The process went relatively smoothly, and I think would be acceptable in future houses.
There is a feature of using tongue and groove wood that could impact the inspection process, and needs to be carefully explored with all the building inspectors before using the technique. A conventional house using sheetrock would have the framing crew enclose the house, with roof, doors, and windows in place, and the interior walls in stud form. The framing crew leaves and the electricians come in. The electricians install all the receptacles and run all the wiring. The electrical inspector comes and does a rough inspection. The sheetrock crew comes in and installs all the sheetrock. The paint crew does the painting. The electricians come back and finish, putting covers on and the like. The electrical inspector comes a second time and does a final inspection. The sequence is clear. Only one crew on site at a time. All the wiring is installed by one crew and then covered up by another crew. That process could happen with tongue and groove siding, but would result in a less than optimum placement of wall receptacles, in my opinion. In a sheetrock system, the receptacle box is mounted to a stud by an electrician. The sheetrock crew cuts a hole in the sheetrock wherever the box happens to be. In a tongue and groove system the box needs to be located in the center of the flat portion of the board, so the cover can be installed flush against the board on all sides. The exact vertical position of the flat portion varies with the character of the boards from one room to another. What I did, and what seems like the best approach, is to cut a hole of the proper size and placement in the board of the proper elevation immediately after the board was nailed in place, and run the necessary wires to the outlet right then. When the outlet is finished, the carpenter continues placing boards all the way to the ceiling. I worked as a carpenter for a time, then as an electrician, and then back to work as a carpenter. This sort of job shuffling is rarely done by contractors, but is not uncommon by the homeowner, who is often given a pass for working on their own house by the house inspectors. The critical thing to understand is that if you want to build your own house, or do a remodel of an existing house, check with all the building inspectors involved.
Moving slag in wheelbarrows and buckets might be acceptable for a single research building, but using slag as aggregate in concrete would be preferred in successive houses. This would be for an entirely different style of construction. The exterior walls (and perhaps the interior walls also) would be concrete. The exterior walls would be covered with insulation, then metal siding. The interior would have plaster on the walls and perhaps drywall on the ceilings. The house would have considerably more absorbing material in the walls, leading to even lower interior field strengths. Considerable theoretical and experimental work on the absorbing ability of slag in concrete was done in 2012 and 2013 concrete.pdf and concrete2.pdf. Results were very positive. But the next step would be to build a batch plant capable of making concrete to precise recipes in several cubic yard quantities. We need to determine a 'good' recipe for the concrete before pouring walls for a house. A cubic yard or so of a particular recipe would be made and samples taken for compression breaking tests. The remainder would be used for something like retaining wall blocks. It could easily require the testing of 20 or more different recipes before we are convinced that we have a concrete with adequate compression strength that will make decent looking walls. Then we pour the walls of a cabin and evaluate the appearance and the absorbing ability. The recipe could get tweaked again for the next cabin, and so on. We might be able to build a small batch plant on the cheap for $50,000. The cost and space commitment for a batch plant is such that we need to be very confident that we have the funds and approvals to build several cabins before taking this step.
AC OR DC?
Back in the 1890s, the War of the Currents was fought between Tesla and Edison. Tesla had invented the AC system, which allowed electrical power to be stepped up in voltage, sent long distances across country from a large generating plant, and stepped back down in voltage for household use. Edison's main argument against AC was that it was hazardous to our health. Tesla won the battle, not because it was more safe but because it was cheaper. A growing fraction of us are now convinced that Edison was right! In my own case, an hour spent in a 10 mG 60 Hz magnetic field will make me quite ill. I know people who become ill in magnetic fields a hundred times smaller or even less. The shop has a magnetic field below 1 mG, acceptable to the mildly sensitive but not to the most severely sensitive. All housing structures built in the gulch will be off-grid and operate only on DC, powered by photovoltaic panels and batteries. The 60 Hz magnetic field will be due to the utility practice of allowing return currents to flow partly through the earth, which early measurements indicate will be well under 0.1 mG.
The next decision is the voltage level, 12 V, 24 V, etc. It is interesting to note that there are economic benefits to society in general if we switch to DC. Much of the electrical load inside our homes and offices is now native DC, requiring a AC to DC converter which is usually not very efficient. If all this load could be plugged directly into DC at the wall outlet, we could reduce our total electrical consumption by perhaps 3 percent. This is a large number at the national level to the people concerned about keeping the lights on, so there is considerable incentive to make it happen. There is a group working on this for the past several years, which can be found at www.EmergeAlliance.org. Their decision is to use 24 V for electronic devices and 380 V for the heavy loads. Eventually, the power supplies of computers, monitors, and the like will be redesigned so the devices will plug directly into 24 VDC rather than 120 VAC. The off-grid units in the gulch will probably have two sets of wiring, one for 24 VDC for the electronic equipment and the other for 120 VDC for lighting. Any 380 VDC wiring will wait until EmergeAlliance gets further along. See electrical.pdf for some additional thoughts.
The shop is heated by electric baseboard heaters. This is a minimum first cost decision and is actually helpful in doing house energy efficiency measurements. I will be collecting energy usage data for at least the next year. A preliminary report is available at MortonEff.pdf.
Swamp coolers work quite well in this high desert with low humidity. I have been using a 24 VDC swamp cooler, powered by PV panels and batteries for several years in my present office/lab in Rockvale, and it works quite well. The Morton shop will have a concrete slab for a floor, with no insulation under the slab, so the slab will be cooling the shop in the summer from the 55 degree earth under the slab. It is possible that the internal temperature will be acceptable without a swamp cooler. If the interior is just too hot, then I will place a conventional swamp cooler at one of the windows.
Incandescent bulbs work well for most people with EHS, but are being phased out by government order, and use a large amount of energy compared with fluorescents and light emitting diodes (LEDs). I will be using my stash of old bulbs for part of the shop lighting. Fluorescent bulbs tend to pulse on and off 120 times per second, which affects some people. The modern electronic ballasts tend to put 'dirty electricity' back onto the wiring. The same noise appears in the light itself. The bulbs contain mercury, a very toxic element in our bodies. These facts are more than adequate to reject their use in the shop and in future housing. That leaves LEDs as a possibility. LED bulbs that directly replace incandescent bulbs are readily available at any big box store. They consume less than a fourth as much power input for the same light output as incandescents. The problem is that at least some manufacturers use internal power supplies in the base of each bulb that put out large amounts of 'dirty electricity'. My Stetzer meter would jump from 30 units to over 400 units when one of these bulbs was turned. Then I saw on the Internet that Phillips LED bulbs were different. I tested a 60 watt (equivalent) version that did not change the Stetzer meter at all. The light output was constant about 80 percent of the time, then would drop down to about half light and back up the other 20 percent, at 120 Hz. The Phillips 100W and the ACE 100W LED bulbs work even better (no effect on a Stetzer meter and no 120 Hz variation in light output). I suspect that many with EHS would function quite well while using this type of bulb. Phillips makes dozens of different LED bulbs, so one needs to watch out for models that do not work as well. Some test results are in ledcomparison.pdf.
Another version of LEDs is a strip, perhaps 5, 10, or 20 meters long and about 1 cm wide, that has perhaps 60 LEDs per meter. The strips have equalizing resistors and internal connections in the copper traces to allow the strip to operate on 12 VDC or 24 VDC. If we have a 24 VDC wiring system connected to an equivalent 24 VDC battery, then an LED strip connected to this supply will have a smooth output, no 'dirty electricity', no 120 Hz component. I have built half a dozen 'luminaires' with LED strips, some in daily use for several years, and consider them a good choice for lighting. Test results for some early work are in the .pdf document ledlighting.pdf.