Edinburgh Council granted permission to the National Records of Scotland (NRS) last Thursday to create railings and a new ceramic tiled floor at its A-listed West Register House in Charlotte Square.
The proposals were made in March when the NRS reported multiple incidents of people defecating in alcoves, drinking on its steps and using needles.
However, the NRS did not link any anti-social behaviour back to homeless people occupying the building, but did highlight incidents of rough sleepers having their sleeping bags set on fire at the property.
The “additional security” measures will be added to the front of the building, which is owned by the local authority and occupied by the National Records of Scotland on a 100-year lease.
NRS says there has been a history of rough sleeping, vandalism and urination in various door recesses and around the perimeter of West Register House in recent years.
The planning application states NRS is concerned the premises could be detrimentally affected by such a pattern of public behaviour.
An NRS spokesperson said: “It is generally accepted that the best way of ensuring the preservation of an important historical site is through continuing use.
“Maintaining and enhancing the quality of the economic balance and social fabric of the historic environment is vital.
“It links us to our roots and it needs to be passed on to future generations in good order, such that they can fully understand and enjoy the place.
“The building is of national importance and considerable significance. This level of significance still permits a level of intervention and change to the building where necessary.
“The changes that we propose to make are largely to provide additional security to the building and the occupants and to replace some of the unsympathetic work that was carried out in the 1960s alterations.”
West Register House is a category A listed building, reflecting its regional importance.
The property was designed by Robert Reid in 1811 as St George’s Church.
With church congregations falling in the 1960s, it was acquired by the government and converted into the Scottish Records Office.