Erection of additonal 4th floor to flats at No.s 1 & 3 Risborough Street; conversion of 1-bedroom flat (3rd floor) at No.1 into a 2-bedroom maisonette (3rd/4th floors); and conversion of a 2-bedroom maisonette (2nd/3rd floors) at No.3 into 1 x 1-bedroom flat (2nd floor) and 1 x 2-bedroom maisonette (3rd/4th floor)