The invention relates to the internal construction of a high-temperature furnace. This internal construction comprises a dome (20) of refractory bricks which can withstand the high temperature within a coal gasification generator. It also comprises a load-bearing brick wall (21) underneath the dome (20). An inner wall (29) is also provided, which consists of refractory bricks and which is arranged on the inside of the load-bearing brick wall (21). The inner wall (29) screens the load-bearing wall (21) from the highest temperatures and can at the same time expand freely, without being subjected by the dome (20) to a compressive force. <IMAGE>
