Continuing with my complete inability to be brief and concise: ;) Plywood has four typical face grades; A, B, C, and D. "A" and "B" grades are the best, with "A" having no flaws in the surface veneer, it's good for stain grade cabinetry. "B" has a nice finish, but can have some patches in it to get rid of knot holes in the veneer, it's suitable for paint grade. "C" and "D" are lesser grades, they are quite a bit rougher than A/B. The "X" refers to the glue being used to glue the veneers together being an exterior rated glue. The glue should not weaken when wet, allowing the plywood to delaminate. So, for cabinetry or furniture, you'd want AB plywood. For house framing (subfloors and wall/roof sheathing, CDX is what you'd want. As to the shower floor, 3/4" CDX ply is fine. If the subfloor were wood planking or 1/2" ply instead of 3/4", I'd add another layer of ply on top to isolate the wood planks from the deck mud or to strengthen the 1/2" CDX, depending on which you have. So once you have your plywood subfloor in place: On top of that I put down a "slip sheet". I use 6-mil poly, some use tar paper. Staple it to the floor, just enough staples to tack it into place. If there is any radiant floor heating under the shower, don't use tar paper. Instead use poly. Over the poly use expanded diamond mesh, that gets nailed to the floor right on top of the poly. Overlap any seams and work to get the mesh flat so there are no "pops" in it when you walk on it. The deck mud then gets packed on top of the mesh, pack it in well and build it up to the required thickness and slope. Mongo

I always encourage people to not do a built-in bench and instead go for a teak-type of bench or stool. A moveable seat ic just that...moveable. You want it in, it;s in. You want it out, it's out. You want is under the shower head, across from the shower head...there it is. If you ever have any medical issues and need assisted bathing, built-in benches are the absolute worst from both the caregiver and the receiver's perspectives. Built-in bench dimensions? Figure on having the finished seating surface about 18" +/- above the finished floor. It's a personal thing, but even going up to 20" high is fine. Higher or lower depending on stature and comfort when getting up or sitting. The depth can be 16"-20" if it'll be for lounging, or 12"-16" if it'll be a foot prop and/or bottle storage and for an occasional rest. If able, my general recommendation is to have a minimum of 42" of floor space in front of the bench. That'll allow decent floor space for someone to shower while another is sitting on the bench. I personally prefer floating benches (open underneath) over built-in (with an enclosed front). Fold-down are an option, but there's usually a weight restriction. There are different ways to do it. A few years ago for a steam shower I built a floating teak bench top that had an open grate design. I built a couple of lugs into each sidewall of the shower, the teak bench top could be placed on the support lugs and you had a floating steam shower bench. When they weren't steaming, they either left the bench top in place, or they'd put it on the floor just outside the shower. There it would function as a teak "drying off platform". The bench top was also wide enough to span their tub and I detailed the bottom edge of the bench apron to nestle on the rim of the tub. They sometimes used it as a bath caddy when in the soaking tub. Different strokes.

I think it can be done. My husband and I just finished building a 1900 sf home in Western Oregon for 109/sf. excluding land. Including the land ( 2-3/4 acres) it came to 145/sf. We acted as our own GC, but hired some of the work out. I'm not sure, but your area may be lower in cost than ours. Our home is a single story- basically a square with a simple roofline. There was already a septic system installed and city water available (so no well expense). A well and septic would have been easily costs us another twenty thousand dollars here. We did purchase our framing material, windows and siding In November of 2014 and I know pricing has risen here since we began. We also didn't anticipate the permit fees- eight thousand dollars,- we had paid two thousand just seven years before, so again, more than we thought. Like you, we wanted to lower our electricity bills. To do this without tremendous expense, we went better than code for insulation - R-60 (blown in) in attic, R-24 in the 2x6 walls and R-38 in the floors. We air sealed top plates and filled in every hole, nook and cranny in the whole place. We also paid the truss makers extra for two foot overhangs on our roof for our south-facing home. No hot sun streaming through the windows in the summer. We went with pretty standard vinyl window but paid for a upgrade for a better, lower u-value. I have no way of checking this, but it wasn't much difference money wise. Another thing we did is went with ductless units for our heating and cooling. We received a energy credit - I believe it was around 2500 dollars. We also installed a electric water heater with a hybrid heat pump that will supposedly Is 70% percent more efficient than a regular electric. Little things that can make a difference is installing LED lighting for all interior and exterior, energy star appliances, and if you can buy land with some mature Deciduous trees, they can make a difference on your power bills. We haven't lived in it full time yet, but we are hoping for a bill in the 90-100 dollar range per month. We'll see how that goes. Just know that things always seem to end up costing more and that it will be a big possibility with your build. When we started out we thought we could do it for 90-100/sf. We spent our personal savings on this home, so it was scary. We didn't have to touch our retirement, and we are mortgage free, but we are broke now and will be working a couple of more years - and we didn't get everything we wanted - I had to kiss my dream kitchen goodbye. I like my IKEA cabinets, but they sure aren't quarter sawn oak. Good luck and I apologize for such a long reply. If you can, please update your progress on here..

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