Enhanced capital allowances

Lucky Ltd purchased the following assets during the period 20 july 2021 to 31 March 2022.
August 2021 computer 6300(cost)
January 2022 integral features 41200(cost)
January 2022 office equipment 32900(cost)
March 2022 motor car 12800(cost)
The integral features expenditure is about a electrical system,ventialiation system and a lift integral to a freehold office building.
Car has zero co2 emissions.
One thing I cant understand here is that in the model answer the computer and office equipment was given a 130% super allowance but the integral features were given AIA and was put in the separate AIA column. Why a integral feature didn’t quality for a super allowance?