Everybody know that Jorbtar want to add two additional types of wall in future. It should be much harder to acquire and it should need to additional infrastructures to be build so there's my idea of brickwall technology:
All you need is skill Masonary, which should be one of end skill and should be hard to acquire. High amount of Arts&Crafts, Sparks&Embers and Law&Lore.
Next you need 3 things to build a initial Corner of Brickwall: Bricks (They are pretty easy to acquire), Bars of Steel (To hardened this construction) and Lime Mortar.
How to acquire Steel? Maybe when you put lime+ore to smelters you'll fill iron bar meter, but when you put charcoal+ore you'll fill steel bar meter and you will get only this one which meter will be full first.
How to acquire Lime Mortar? You'll need additional structures like Lime Pits. First you have to collect or dig big amount of lime. Next you have to put all your lime to kiln (or other special structure like Lime Kiln) to burn them. You'll get Burnt Lime (Quicklime). Now you'll be able to build Lime Pits and put there Burnt Lime and dozen buckets of water (Structure is similar to coal clump) and next you have to wait 2-3 days to get Lime Mortar (Lime Mortal is better when lay much more irl).
Finally you are able to build Brickwall which in sum cost pretty much of Iron, Lime, Charcoal and Bricks.
