What size are your precast columns? If 15cm then perfect for use of 15cm q-con. You can save a bit by using 10cm q-con for internal walls.
Recommend you go with standard sized upvc windows purchased from home mart, global house or whatever in Chachoengsao. Several sizes available.
Originally Posted by Slick
Use a breaker unit with Main Power, RCBO, and several breakers. Leave extra punch outs for circuits you might want to install later.
Wiring all 3 wire ground. Get copper ground spike from local supplier. I would go with more than one power outlet per room. At least on per wall.
Depending on available village water and sewage some thought needed on what you need. Most village water supplies are iffy. Low pressure, frequent loss of supply and cleanliness problems. Best to have holding tank, filter and pump.
Likely you will need septic system. I have 2. One a simple single concrete tank for grey water and another 2 stage (one upvc feeding a concrete tank) for sewage. Have a small pump on grey water we use for watering garden.
Flooring up to you but make sure tile is good quality or troubles in future. Non slip in shower a must!
Enjoy. Looking forward to your build pics.