Right the answer to your question is that the joists should normally be at 400 mm centres on a normal built house and they would probably be 9x2 joists but if the span is over a certain length and if you asked building control at your local council they would specify the maximum length for the size of your joists and once the span is to long for 2 inch joists you would have to use a 3 inch wide joist the joists should over lap the wall by 4 inches from both rooms and also they should be along side the joists from the other room and the wall below should be beam filled to the top of the joists for fire protection and also to stop the joists from warping and then the flooring above can be screwed down upto the stud wall above what would be fixed solid to the joists I hope that you can understand my answer thanks

需求排序因非消防安全性,而楼上 stud墙不安全性最强,因为大多数人使用100ml或更大螺丝并直接螺旋入地表慢冲器,砖工应跟踪木头以确保没有防火漏洞扩散

横梁或砖块填充需要保火墙和固定固态墙间必须倒置固态才能造出坚固 stud墙 150mhiavey值班螺丝直插地