Sorry I do not have any advice or tips, looking for some advice on how to build trombe wall or for a greenhouse.
So I have many pcs of double pane glass-sealed units. The question is: how do you attach them together with an air tight waterproof seal. I have seen a way to use a 2x4 and make a rabbit joint as to join two pcs together. So one question is, do you use caulking or a gasket of some sort next to the wood. And how do you cover up the seam on the exterior so that it seals forever, metal flashing or wood and is there a special type of tape or gasket you use on the exterior.
Obviously looking for earth friendly non off-gassing products, if possible. Could you cob it all up and then cover the cob with metal or wood to protect it
Any tips or links to sites with details and possibly drawings would be great.
A true Trombe wall (glass, air-space, cement, inside of house) is very inefficient. Much (some say most) of the heat absorbed by the cement during the day is radiated back out through the glass at night. If you don't have sunny weather, the cement cools down and you lose a lot of heat.
There are plans on the net for "solar furnaces" that direct hot air into the house. These work great during the day, but rely on high thermal mass inside the living area if you are trying to use the solar heat 24hr/day. I know a lot of people get all sorts of warm fuzzy feelings thinking about thermal mass, but if it is not well balanced and inside of insulation, it can result in either an uncomfortable house, or one where the occupant is constantly adjusting drapes, insulation and ventilation.
There are several solar heat groups on groups.yahoo.com and plenty if plans on the net. Like everything else on the net though, you'll have to learn enough to know what stands a chance of working and what is somebody else's pipe dream
Many Trombe walls are built a short distance inside the home. This allows for the addition of thermal curtains or other insulating devices, so there is no need for inefficiency.
My Trombe wall will be built around my rocket mass heater so that it may be heated with firewood on days when the sun is inadequate. I'm planning to go about 6 feet north of the south facing bank of windows. The earthen floor will also absorb plenty of heat so there's no need for this distance to foster any inefficiency. The mass heater on its own will weigh several tons so it makes sense to allow it to be solar heated on mild days. Window seats made of cob and other heavy, dense structures can serve as Trombe walls if situated properly.
Trombe walls are one of the simplest and easiest solar energy systems to manage. No electricity, nothing to break down. The only moving parts are the curtains and possibly a blanket which is tossed over the wall if heat is unwanted. The blanket is removed later in the evening when heat is desired.
I agree with Paul. Why have a trombe wall when you could have more windows and floorspace with better efficiency? Paul, interesting solution but wouldnt that just be additional thermal mass as opposed to a trombe wall?
"If you want to save the environment, build a city worth living in." - Wendell Berry
I would do it pretty much like you said. Build a wooden frame that is rabbeted so the the glass sits flush with the outside plane of the 2x4s, and the vertical 2x4s would be double rabbeted so that each pane has about 1 1/2 inch of bearing. Then find some metal strips that were the vertical length of the glass and about 3 or 3 1/2 inches wide and maybe 1/8 or 3/16th inch thick and some thick rubber (such as a threshold material sold near the doors at your hardware store), trap the rubber between the metal and the glass and there you have it.