Nobody was injured in the incident which occurred on 10th January during works for the redevelopment of the Edinburgh St James Centre.
A spokesperson for Laing O’Rourke – which was formally appointed as construction partner for the project in October 2016 – said: “During demolition of the multi-storey car park [on 10th January], two floors of two structural bays collapsed into the demolition exclusion zone.
“The exclusion zone is an area where personnel are not permitted and specialist machines work from the perimeter on the demolition of the building.
“The exclusion zone is further protected by a safety zone where only trained personnel are permitted.
“These measures are put in place to keep members of the public and site personnel safe at all times and allow for the unpredictable nature of demolishing buildings of this age and condition.
“As a result of these measures, nobody was injured by this localised collapse."
The retail and leisure elements of the St James development are expected to complete in 2020, with full completion scheduled for 2021.
The 1.7 million sq ft project will include 850,000 sq ft of retail space, 150 private apartments and a 214-room hotel.
Additional features will include a multi-screen cinema and a branch of John Lewis.