Energy & Environmental Appropriateness
Energy Performance
Building with thermal mass is a fundamental first step if your intention is to dramatically lower, eliminate, or even reverse energy consumption for heating and cooling in buildings. The data below shows a one week period in a SIREWALL building that had been unoccupied and had the power shut off for three weeks. With no assistance from any active mechanical systems, the interior temperature and humidity maintained ideal interior levels.
(You may wonder what happened at the end of the week. It was the data log devices' ride home in a car, and on a ferry.)
Had this building been occupied, it would have not needed any heat during this period, even though outside temperatures fluctuated significantly and never approached the internal temperature of the building. This is what a totally passive (meaning no mechanical equipment) net zero energy solution looks like.
Radiant heat makes you feel comfortable at lower temperatures, as any radiant floor contractor will tell you. ASHRAE (American Society of Heating, Refrigeration and Air Conditioning Engineers) studies confirm comfort is achieved with radiant heat at a 6° to 8°F lower ambient air temperature setting than convective systems.
Convective systems, more commonly known as 'forced air' systems, are the predominant means of heating and cooling buildings in industrialized nations. With no thermal mass to stabilize temperature differentials, we rely entirely on energy and maintenance hungry machines to heat or cool the air within spaces we inhabit.
Subtract the desired interior temperature from the exterior temperature, whether the challenge is heating or cooling, and that difference is what all that costly, sophisticated, maintenance needy (and, seemingly always just at the worst moment, unreliable), ultimately unsustainable whirling and twirling machinery will be busy pouring energy into controlling.
A SIREWALL structure will have abundant mass on the warm side of a continuous insulation barrier - hundreds of tons of mass consistently acting like a huge thermal battery that very gradually charges or discharges, depending on what is happening around it. Thermal energy flows like water, and always in one direction; from the warmer to the cooler. This makes SIREWALL ideal as a reservoir for energy generated by low impact systems such as geothermal or passive solar. Sunlight pouring in through a window will 'recharge' the mass with energy that will radiate back out of the wall when internal temperatures become attractive to that stored energy.
Building with insulated thermal mass opens up the option of dramatically scaling back, or even eliminating, all that costly and needy machinery, trading it in for a building that keeps us much more comfortable and costs far less to feed, regardless of what is happening around us - heat, cold, wind, rain... this is what shelter should feel like.
Environmental Appropriateness
Building with organic material - "building from the topsoil" - is by definition building with materials that are part of the soil cycle. Nature has a plan for organic material; it is supposed to return to the soil. It is supposed to rot, decay, or combust.
Whether it is a kiln dried stick of lumber or a bale of straw, if a building material is derived from something living, it is part of the soil cycle, and to remove the tree from the forest or the straw from the field is to deplete nutrients from the soil that are the living substance of that forest or field.
Poor stewardship of topsoil has played a significant role in the decline of virtually all fallen civilizations. Today, we rely heavily on petroleum based fertilizers to support industrial production of both food and construction materials.
To 'build from the topsoil" is to commit the triple error of:
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Depleting soil nutrients to
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Harvest organic building materials that will soon
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Add to our waste stream as toxic demolition waste.