In case Tony/Incognito doesn't answer right away about the herbicide impregnated root barrier, this product is used in urban street plantings where surface rooting is to be discouraged, and it actually does last for a very long time, but would probably need to extend at least 2 to 3 feet down vertically, or until you hit bedrock or a soil depth where there isn't enough oxygen in the soil to encourage tree root growth. The possibility always exists that tree roots can still grow under it and then into the new area, but typically it is the main principal roots that tend to serve as anchor roots for the tree's stability that do the most damage to pavement, and on older trees like pines these tend to stay near the surface, but that will vary greatly on your soil type and soil moisture conditions at different depths. Your arborist/consultant should be able to advise you more specifically if this herbicide impregnated root barrier makes sense to add against the new curb/wall to help protect it. I wouldn't rule out other sun loving bromeliads for this sunny situation, things like the more terrestrial growing Puya or Dyckia species might be good choices, and it also sounds like this thin soil, sunny area full of tree roots might be an excellent location for clumps of Agaves such as A. bracteosa, A. 'Sharkskin' or A. parryii cultivars, or in combination with things like Echeveria agavoides or Bulbine frutescens. Aloes such as A. saponaria or A. striata would also do well there. All of these plants would grow better if planted in a new layer of topsoil added over the tree roots, and given at least a monthly periodic good soak, or more often depending on how quickly/lushly you prefer them to look. California natives such as Mimulus aurantiacus, Salvia clevelandii or S. leucophylla 'Pt. Sal' could also look good here, or even more adventurous plantings like Metrosideros collina 'Springfire' or Metrosideros collina 'Tahiti'. A really cool looking green fuzzy flowered Aloe such as A. tomentosa would probably also do well there, or other Aloes such as A. castanea, A. camperi, A. rubroviolacea or A. vanbalenii.

Keep at it! I cant wait to see how this turns out. We have a 1897 farm house here in TX that has floors similar to you. We are not sure the wood, as it is painted, and has been since my folks bought it back in the 1980's. I have not yet had the time to start the stripping process but I would love to one day. This house has a lot of history, as 11 children were born and reared here. I am afraid of all the sanding, to get some boards even but I want to leave some of the wear, as it has character. One room at a time may be the way to go. The bead-board was once painted grey (by the previous owner) like the staircase the original was stained (one room upstairs still is)and we painted it white. The banister is original. The treads are all hand cut by the builders. I want to restore them first. Here is the house itself with new Hardie-board siding

That is how ours looked before and after too ! You will love them. We use a damp cloth ( I save old washcloths) and put it on the Swiffer head and push it around to collect dust and dirt. It works great and is cheap. You just rinse out and wring it very well and keep on. Takes minutes and the floors always look wonderful. I use Murphy's Oil Soap for heavier cleaning....there are pros and cons that have been expressed on this forum...I like it and it does a great job. Good Luck, Caroline

This won't be an inexpensive remodel. You are creating redundant spaces. A den, living room, and family room. A breakfast table and bar stool area. The kitchen layout isn't so great, especially since you are thinking about doing a downdraft, which is particularly ineffective for the extra dollar amount spent to create it. You're also taking down the barrier wall around the stair? It's not that attractive to open a door right into a living space when you can have an actual entry way that give you a sense of transition between the outside world and the home. You'd better think about the ramifications of taking down that center support wall. Not only will you have to engineer support for the roof, but each of the ends of the beam that supports it will need new footings or support in the basement if you have one. And you've placed a fireplace right in the middle of where the beam will need to be. That's not going to work. It will have to shift one way or the other so the vent can clear the support beam. You can do SO much better! I'd suggest contacting an architect that specializes in remodels and has some sympathy for mid-century or contemporary home designs. And clarifying your actual spatial needs to avoid duplicating them.