Phillip Stuckemeyer wrote:I am planning to build a greenhouse on the south-facing end of my house. It is a perfect solar exposure, and will feature an aquaponics system with Tilapia. The fish tanks will be in the cellar where I can control the temperature, and the growing beds will be in the greenhouse. The greenhouse will provide passive solar heating for the living space, and will be augmented with one (maybe two) rocket mass heaters for the night time and periods with minimal winter sun. I have provided a picture to show the south end of the house, which is about 35 foot wide. Notice the windows in the cellar and the windows in the living space... rising hot air will easily heat the house. I am contemplating a building plan based on the book Secret Greenhouse of Survival by author Rick Austin, but am curious if the Bioshelter Market Garden design might offer some advantages. A concern is the smells produced by the fish tanks. I am hoping that a veritable jungle in the greenhouse will ameliorate the potential smell, but am not sure. It will be an experiment. Has anyone tried this?
Phillip Stuckemeyer wrote: I can feel air entering the lower 2 vents, and cool air rising in through the three upper vents, but it seems like it take over an hour for the air to feel warm.
Phillip Stuckemeyer wrote:I am considering a foil backed, insulating blanket. By closing the shutters on the blanket it should stop the airflow for all 5 vents. I am also considering a temperature actuated damper in the bottom of the box activated by a thermo-bulb mounted in the riser duct. However, all these options seem like a waste of effort until I reduce the volume of air in the heating chamber. Week after next I will cut the box down to size and post an update with pictures of the inner workings. Traveling on business this week.
Mike Haasl wrote:When I first saw your trombe wall sketch I thought it was brilliant and I still do. I thought you were going to provide the cold air from the lower window, let it sink to ground level and then let the greenhouse effect heat and raise it to the upstairs window. I think that would really help it to move air.
Mike, you are correct about my original intention. However, the bottom windows open to the cellar, and there is no direct air flow path from the house interior to the cellar. I plan to house tilapia tanks in the cellar for an aquaponics system once the greenhouse is built, and the smell of the fish tanks is another concern. I was a licensed tilapia grower in Virginia, but a sudden freeze in my detached greenhouse killed all the fish. My current plan is to locate the fish tanks in the cellar, and the growing beds in the greenhouse, and to pump the water through the wall. A Rocket Mass Heater (maybe two) will be added to keep the greenhouse within temperature tolerances in the nighttime and on cloudy days.
Ebo David wrote:An idea and a word of caution:
Take a look at thermoactuators (wax motors). You may be able to come up with an arrangement where a couple of them push/pull a control rod to track the sun across the sky without the use of electronics... I know of some dead simple analog circuits that basically do the same thing, and require no computers. If interested, hit me up in a couple of days and I'll see if I can find reference designs on the net.
Most fire-codes require that there be at least 2x egress points from each room. You are effectively blocking off the emergency access out of the bottom window. In case of fire you or someone might need to crawl out that window. Please think about how you will accommodate that..