Crawl Spaces

Under the AAC house envelope there is a low crawl space. This crawl space was necessary in order to put several important system components. It also provides an extra measure of insulation by establishing a relatively dead airspace under the house. The house envelope rests upon thick brick walls which provide it a level surface to sit on. These brick walls divide the crawl space into two completely separate long, low and narrow areas. The ground surfaces were left bare. The walls were painted white - in order to make visibility easier with limited light. Each crawl space has a small 80 cm square metal door entrance at the east wall. The interior ground to ceiling height at these entrance doors is about 1.40 meters and gradually decreases moving toward the west wall, where the height is about 30 cm.

The south half shelters the renewable energy system's house batteries. It also has an 80 cm by 60 cm brick pillar that sits directly under the 700 kg masonry stove location in the house and provides the AAC floor panels with the necessary extra load-bearing support. The batteries were placed directly under the location of the power center, inverter and converter within the house - they need to remain close to minimize electrical resistance within the connecting wiring. Due to the low 90 cm height of the ceiling at this point, a 60 cm deep hole was dug into the ground in which to build the concrete and AAC battery box. This box was built between the central brick wall of the crawl spaces and the masonry stove support pillar. Within this box are eight high capacity house batteries wired at 24 V DC. A ventilation tube runs from this box to the exterior and has a vent fan incorporated within it near the box. In order to ensure adequate replacement air for this ventilation fan, a number of holes were drilled into the metal entrance door.

The north half shelters the composting toilet's batch composter unit. This rotating four-chamber batch composter is situated directly below the two toilets of the bathrooms; each toilet dumps straight down into a separate chamber. This composter decomposes the wastes over several months into a highly beneficial, fertilizing humus. When the chamber under the master bathroom toilet becomes full, the chamber with the oldest humus is emptied and then the unit is rotated clockwise to place this empty chamber under the guest bathroom toilet. The humus is then used to fertilze my fruit trees. I had also originally planned to place several other system components within this crawl space but at the time of construction decided against it because of the inconvenience of regularly going in and out of these crawl spaces. While the composter only needs to be emptied several times a year and the batteries only need to be maintained several times a year, these other system components require tasks that need to be done much more regularly.

I made a small AAC closet addition to the exterior side of the crawl space brick wall so that the necessary, regular tasks would be easier and more convenient to accomplish. In this back wall enclosure is the urine bucket; my ceramic toilets are specially designed to separate the urine and the feces with the feces dropping into the composter and the urine flowing into a collection bucket. This collection bucket needs to be emptied about every ten days; I use this urea to fertilize the trees on my property. The back wall enclosure also has a wastewater overflow chamber to handle situations where excessively large quantities of water are drained through the waste plumbing at once. Within this chamber I will put screen nets to filter out large substances from the wastewater, filters which will require emptying several times a month; these substances will then be put into my garden compost bins. Within this insulated enclosure I will also have a pressure pump and pressure tank to pressurize the house water. I have located them here because I have placed the home plumbing's main shut-off valve in this enclosure, and it was more practical to locate the pressure pump and tank in the same place.

Since there is a lot of space left within these crawl spaces, I try to take advantage of it. I use this extra space to store wastes, such as paper, glass and metal jars, construction foam cuttings, etc., to either be reused or recycled later on. I always keep an eye out for opportunities to put these wastes to good use. I also store excess firewood in these crawl spaces to keep it out of the weather. And I also store other odds and ends that do not require frequent trips.