Thanks for all the answers macv. We are not concerned about the dust during installation as much as we are concerned after. When painted drywall is done it collects dust faster than slick plastic like the kind in bathroom which is what we are looking for or something similar and painted drywall doesnt stand up to repeated moist cloth wipe downs as well. If we have to go with drywall then we will and it wont be the end of the world but just looking for something made like the plastic/fiberglass stuff you see in restrooms in commercial applications.

Still not any closer to deciding what to do. Been busy trying to get the building plans approved. It was suppose to be close to approval back in March. We are still waiting. We were told by our architect that we could not keep the existing redwood exterior siding as we are in a Wildlands Urban Interface area. He suggested stucco. We saw there is a WUI approved product list for California and talked to some of the vendors. We currently have 1x8" tongue and groove vertical redwood siding and the vendors told us that is WUI compliant. Who should I believe? We would prefer to keep the wood siding. Because the existing exterior is somewhat neglected, we are wondering how we can get the wood restored and how it will look with new 1x8" redwood siding that we will need to put in for the addition. Will this be the same kind of professionals we need to get a hold of as the ones suggested for the interior paneling? Thanks in advance! Here are a few pics of the exterior siding:

Ok wait, last one, (for now). this is simple to make. Please swap walls though. since you have those beautiful wood floors, and I love black with it, what if you did a vertical black wood wall? you could do those DIY black slats (paint the wall black first) or, do the vertical shiplap. You could buy cheap pine flooring and paint it once on the wall. or you could take plywood and rip your own panels. or you could buy MDF ready made shiplap (costs the most). up to you. Basically looks like this Just look at the wall panels, nothing else!) Now, bring in the lighter rug w/either the black leather sofa, or the camel color (don't know if you saw mine. I got their sofa,bench and chair) Look how pretty that would be w/this vertical black panels. you could warm things up w/this color rug. (even has a similar lamp you like) so imagine this sofa on your other wall, tv w/the black panels on the smaller wall, art, plants, maybe these two poufs. don't know if you could squeeze in that large ottoman. maybe you could use it as a coffee table? once that sofa is back against the big wall you may have room. or do the leather color sofa w/black/white pillows/artwork art behind the sofa, or do a nice shelf w/decor items. this one is a little plain, but you get the idea. Don't forget your greenery. if you want a diff color sofa, they have many others,,blue, green: Charcoal gray or, the lighter silver colors. sorry for all the pics. I really love this for that smaller wall though. even if you only do 1/3rd the wall w/the slats (look up more pictures) I think it would look so good w/your great lighting and your floors

if i eliminated the linen closet, i would have up to 64”, 64x47” available for the shower. entrance door to bathroom is 24“ wide. the wall to the left side of the entrance is 36”(side of vanity is on), linen closet is 23”deep. (wall between powder room and kinen 5”). the existing bathroom is 47x 90” how can i fit a doubke sibk? what size? what size to make thr shower? wherr to habd towels?id like a bench in the shower. wish to have a 2 person shower.