Ive made myself a fairly large porch area on the front and side of my house. Im in the UK but Ive always liked American style porches, so ive ended up with a porch that is 7.5m along the front and another 7.5m along the side of the house, and it comes 2.5m away from the front and side house walls. So its pretty large. Now I want to make a roof for it and Ive been through many options in my head and Ive ended up deciding on half glass, and half wood. Because its pretty large and deep, if it was all solid roof, I'd lose a lot of light to the house windows. It cant be all glass either though, or might well be too hot in the summer. Im also hoping to have a system where I can roll down material over the glass on hot days, to act as a shade to prevent the glass heating up the porch area too much.
Ive worked out I need toughened glass, and the costs aren't too bad - something like £50 for a single 1500mm x 1500mm piece, and I'd need 5 of those for the front (im leaving the side of the house all wood) so its not too expensive. Im just not sure how I go about fixing this glass to my joists. I have 6x 4" (1000mm) square posts along the front of the porch upto my height of around 2.4m (each one is about 1.5m apart). I have 6x2 size joists connecting the posts along the front at my height, and Im going to run 6x2 joists from the house wall on a slight slope down to the front posts. Not being a professional woodworker, Im just not sure of the best way to secure the glass, and to also ensure it doesnt leak at the joist sides. Do I run a strip of wood along each joist, just below the top, and sit the glass pieces on that? And do I need to use putty to seal each one? Or is there a better way of doing it. Any help on this will be really appreciated, or any links to how this is done well to make a nice waterproof seal. Also am I being too ambitious in thinking I can manoeuvre these large pieces of glass into place on my joists in the first place! And will they be safe enough (toughened clear glass). Thanks all.