There are tires are used in the the north retaining and southern foundation walls, but not shown as tires. The south facing glazing is double paned glass and set at 55 degrees for best solar exposure at winter solstice at 40 degrees latitude north. Cooling tubes run through the berm and the top windows open for ventilation. No insulation is used, although rigid foam in the berm would help to keep greenhouse warmer at night. This Greenhouse was designed to house an IBC aquaponics system with 3 beds a 275 gallon fish tank and a 150 gallon sump. These water tanks will provide additional thermal mass to stabilize the interior temperature.