dragonfly, I can't imagine using hypertufa for a pond liner. I use the recipe with peat moss and the peat moss degrades over time giving you the lovely nooks and crannies. I've made bird baths and fountains with hypertufa and you work the mix to bring the "cream" to the surface. The "cream" is the finer particles of portland, sand and in this case small amounts of peat moss rise to the surface. Similar to finishing a smooth sidewalk or patio. Some people on this forum line their creations with mortar where the water will wear away the surface or something like a bird bath that you would scrub. Well, maybe you wouldn't scrub your's but I do, lol! Billie

Maybe someone else can give you picture posting instructions, though that information is somewhere on this forum. I have my photos that I post on Photobucket. You can use aluminum flashing, large plastic trash cans, large plastic pails with the bottoms cut out and duct taped together to make molds for pillars. There are many things you can use for molds. Just make sure you use the right "release" e.g. plastic bag, motor oil, vegetable cooking spray. When using a bottomless mold make sure you have adequate weight on the top or the mold is tied tight to the ground or the mold will float up as you add cement mix. You can use PVC tubing or smaller plastic buckets taped together if you want the inside of your pillar to be hollow. Have you asked at local carpet dealers if they have cardboard tubes for their rugs. Pretty soon everything you look at will become a mold. Good luck! Billie

Redwood is a nice, long lasting material, but it isn't IMO environmentally friendly. Redwood is old growth forest materials, and due to decreasing amount available becoming prohibitively expensive. I would look at western red cedar or pressure treated or as an alternative some of the composite materials now available. (I like the looks of the composite posts that are available, plus they don't rot.) As to the issue of support, no matter what materials you go with, your support beams will need to be sufficiently heavy enough to span the distances between posts, carry the beams over them, and whatever weight you will add in addition to that. Since your furthest distance is 14'8" I would use at least a 6x6 post set on a bracket attached to the concrete. Then your load bearing beams should be no smaller than 2x8 or 2x10. (This might be a bit of overkill, but you normally use at least a 2x10 set on 16" centers for a floor when you span up to 14 feet.) I would double these beams. (Place one on the outside and one on the inside of each post.) They need to be attached by carriage bolts ran through both beams and the post. If you want, or code requires it, use a galvanized bracket to provide additional support to the beams. Next you will want to run cross beams to provide side to side support for the posts and load bearing beams. Attach them to the load bearing beams using floor joist brackets and the proper fasteners at any center posts. On the ends I would also double these the same way that you did the load bearing beams, but overlap the posts and butt them into the load bearing beams using the appropriate screws through the outside beams and into the post, on the inside use the floor joist bracket. If you do not want the cavities between the beams visible from below you can place either a 1x6 or a 2x6 in there and fastened from the sides through the load bearing beams. This will also give you a chase that you can run electrical wiring through for lights or outlets. Now you can attach the top cross beams, for these you can use 2x4's or 2x6's set on edge and toenailed into the load bearing beams and a ledger plate you have set at the same height as the load bearing beam on the posts. I would also attach hurricane clips onto each cross beam. You can do this on both ends of each one, but if you at least do the ones on the load bearing beam you will be getting a great deal more wind resistance and seismic stability than you ever will without them. As to the ledger plate you need to remove the siding and attach it using lag screws, at least 4 inches long, into each stud. You will need to put a piece of aluminum flashing under the siding, and bend it to make a 90 degree angle onto the top of the ledger plate. You will need to caulk under the siding where it overlaps the flashing or use an appropriate means of securing the siding if it is vinyl. The main thing I can tell you other than the above is to make sure everything goes up squared and level. The first thing I would do is measure out from the house at each end the distance to the outside of posts, then snap a chalk line on the concrete. Your drive pins should be at least 2 3/4" inside this line. This will be your outside reference line. Now check the retaining wall and patio for square. Either place a steel framing square onto the patio with one side on the chalk line and slide it against the retaining wall. If there is a gap at either end of your square, then you know that the retaining wall is out of square and you should not attach your post directly to that wall. Next check the retaining wall for level. Take a four foot spirit level and place one end (narrow end) onto the patio and place the level against the wall. If the bubble in the vial does not line up in the center the vial, the wall is out of level. Depending on which side of the center line the bubble is on, you will either be leaning in or out and will need to adjust your attachment to the wall to correct level. Now, take your level and turn it so that it is standing flat against the retaining wall, with one end lined up on the chalk line, and tilt it at the top until the bubble is in the center of the vial. Run a marker (pencil) along the side of the level to mark your level line for the front to back of the first post. Now go do the same thing on the other retaining wall. Not as easy as you thought, huh? Things never are when you do it right, and we still aren't done with the lay out! Measure up on the side of the house and remove the siding at a level equal to the height your load bearing beams will be on the posts, plus the additional height required to get up to the tops of your cross beams. Now we need to attach your brackets to attach the retaining walls. Measure in 2 3/4" from the level line you made on the wall, measure down 6 to 8 inches from the top of the retaining wall and mark it. This point is where you will use a masonary bit of the appropriate size in a hammer drill to insert a drive pin at least 5 inches long and a 3/8 " in diameter. You will attach a standard U galvanized steel post bracket to this drive pin with a lock washer and nut. (This is if you are using a square post, for round or turned posts you will have to adapt or abandon doing any side attachments.) Now take the post and slide it into the U bracket. If there is no drive points in the concrete under where the bottom of the post sits, after you level it, then you will need to drill it and install a drive pin for the post bracket. It will need to be the correct distance from the wall and the chalk line, 2 3/4" in and away. Now attach the stand off post bracket to the drive pin, and put the post into place. Take two deck screws and run them into the post from opposite sides, closest to the wall. Now place your level against the post and slide the top in and out until the bubble is centered in the vial. Mark the post along the edge of the U bracket that you attached to the wall so you will not loose level when you set down the spirit level. Run deck screws into the post from opposite sides so that it is now secured to the wall. Go do the post on the opposite retaining wall using the same procedures. If the post needs to be shimmed between it and bottom bracket, do so using materials which will not deteriate. Finish attaching the bottom bracket to the post using as many deck screws as there are holes in the bracket. I am sorry but I will have to come back later and finish these instructions. If you need more information I would suggest you look for books put out by Sunset on outdoor structures (Pergolas, Gazebos, Arbors). Most of thier publications are very informative and can give you good general design/construction instructions. Of course, check with your local code enforcement office. They can give you specific requirements for your area.

You will need to somehow add support beneath the existing deck surface. We did something similar using cedar 6x6 posts anchored with Simpson ABU66 post bases into 3' of poured concrete 12" footers. I removed deck boards where the posts were to be placed and used a two-man auger to dig the holes. Our plan is to replace the deck board anyway. If I could post a photo, I would.