The school has limited funding, consideration must be given to this. Everything costs money and unfortunately some things take priority over others. Sensory areas are great ideas, great places, however it all costs money. Perhaps the school have plans to do this at a later stage? You should be happy with the new build as it is and not want more all the time. You have got a fantastic brand new state of the art school with tax payers money and you are still not happy. Just be satisfied that you are not in a 1960's building with singled glazed windows and asbestos everywhere.
 

All this is excellent but I am not impressed with the new build schools in terms of the actual quality of the learning environment for children, especially children with additional needs in the sensory areas. The first priority should be to enable all children to learn effectively - most of these schools have unsuitable lighting for ASC children, and they do not have quiet spaces for individual learning and respite for children who get overwhelmed by environmental factors such as noise and bustle; they meet the regulations but not the needs of our children. Award winning buildings so often miss the point of what the building is actually supposed to do and modern schools are prime examples of this.