I live in the far NW near Seattle, and would love to have a brick wall facing the sun, without nearby trees. However in the SW, could this wall retain heat in the summer to a point where it may be hard to grow due to high heat retention? If you are planning a Fall-Winter-Spring garden, then this may be ideal for warmth and sunlight (so scarce in the NW). Ventilation will be crucial when the sun is out and late into the evening that day as well. Temps will soar much more than would seem reasonable, and that wall will put the heat back out for much of the evening.
As to construction, do you plan for this to be a semi-permanent structure or a trial location?
If a trial, then leaning PVC pipe against the wall and covering them with heavy duty "clear" plastic, or white (opaque white) to diffuse the sun, may be a good trial workout for a year or two. I would consider something more permanent only if you were an experienced gardener and were CERTAIN that this was a good location. Using heavy 20-30 pound blocks to anchor the poles and hold down the plastic at the bottom may prove useful, if the wind blows heavily. Zip ties can prove useful as well.
The primary consideration is which way the wall faces. Does it run N-S or E-W or on a different line?
As LLoyd says, the material and design will depend upon the level of permanence and the use of the structure. Many garden supply houses sell AG film which is treated to hold up under heavy UV light from the sun...the plastic at the big box stores won't last on season here in Miami. I have built several greenhouses and air circulation is also a big deal especially in warm/hot weather.
This was our first Winter with our AP greenhouse and we absolutely love it.
I wish you well with your hoa as I have heard the horror stories. Personally I will never own property again that is in a "Historical" zone or an hoa as I believe in property rights. We have made large sacrifices to finally live in a free area which also has a wonderful climate here in the Mtns. at 3000 ft.. TN is still one of the free states where the politicians aren't in your pocket but rather are still on the side of private folks like us. When I send pics of our 16 x 24 garden shed and 20 x 24 GH to friends back in MA, the first words out of their mouth is "OMG, what did those permits cost?" My answer: What permits? That is freedom to live as one wishes.
Just something to consider if you get the chance to make that decision of where to live in the future. Our attitude is: when you start paying my property taxes then you can dictate your terms. Until then stay the hell out of our lives. The Fed is bad enough.
Due to this "freedom" I was able to make the GH in stages. This last year we got ready for Winter using 4 mil poly from TSC which has endured 8" of snow twice now. Makes me nervous as hell but so far so good and this Summer we will recover it with Poly Carbonate clear panels and double insulate the inside with the 4 mil. We have survived this Winter down to 10F at night with no insulation thanks to our home made wood stove and a few acres of our own trees. (Another thing on our list of must haves when we were property shopping as I have heated with wood for 45+ years) That is another consideration. How are you going to heat it in the Winter?
Our "fish room" is on the N side of the GH and separated from the "hot house" side by a wall so as to maintain 2 temperature zones and that has worked out really well. That room has a metal roof with 3 skylight panels. The entire peak can be opened in the summer for ventilation. The system water (2000 gal) makes a great heat sink and gets thru some cold nights (around 32F) without any help unless we have had no sun for days in which case the wood stove also heats the water (and dries out the air which is a big deal in the winter GH).
I'm pursuing something very similar to your project and also negotiating with an HOA; their interests are similar, as this is not a rural homestead setting and all residents have concerns regarding appearances and property values. In addition, we have to address our big government's insistence that we meet hurricane high wind design, so that pieces of our greenhouse don't end up in our neighbor's living rooms during the next storm!
We're matching the house concrete block and stucco, and the non-glazed part of the roof will match the house. Glazing will be twinwall polycarbonate, of thickness and fastening method required to not blow off. Size is same as yours; south wall is vertical to 10 feet high; roof is gabled, with south side mostly glazed.
I do not have the benefit of the existing brick wall as thermal mass, but 600 gallons of fish tank water will help with that. You may want to paint the brick a white color inside the greenhouse to increase light diffusion in the space, which will somewhat reduce its heat absorption during the sunny part of the day - get help in choosing the paint system (adhere to brick, zero VOC, food safe) and prep the brick carefully. I doubt that thermal mass will be as much of an issue in your location as will adequate daylighting for growth. Keep us posted with pictures!
Don't expect enthusiasm from the HOA on the plastic sheet. If I lived there, I would scream if a neighbor did that. Next would be Ma and Pa Kettle's chickens in the front yard, and Junior working on his stock car in the driveway. That's fine for a rural setting, but not so for places that have an HOA. I sometimes think I'd fit in better out where I could have a few chickens in the yard.
Im still in the plnning phase of my greenhouse and have not really thought about heating. Now i have just been using fish tank heaters to keep my fish tank warm. Thats been working great for the garage. My backyard isnt big enough to for a second fish room but i have been thinking of putting the tank mostly underground. I think that would help with space a little and i would be able to build my growbeds above them. i think building in stages will be my best bet. I can build my frame and cover it with plastic and if it works out i was considering the polycarbonate or glass. I guess ill have to write it up and see what my hoa thinks. This is my first home and i agree the hoa has been more of a pain than anything else.
the HOA thing reminds me of this joke ad;
"Assemble in an afteroon...
Disassemble the next day after HOA citation"