The post office, formerly a federal structure, is a designated historical building and its facade is protected under the Ontario Heritage Act. Lambton County Developmental Services purchased the building and retained a+LiNK to develop a new program for the derelict structure.

The interior of the building was stripped to the base structure to remove hazardous materials saving the original feature stair between the first and second floors. A new interior layout was designed to accommodate six residential units, a retail store, a catering facility and a restaurant space. A new elevator and code compliant exit stair were added to the rear of the building purposefully angled to be concealed from the street view. As a part of the renovation, a full restoration of the original wood windows was completed and a barrier free access ramp was added along the east façade. The existing one storey rear wing was converted to a catering kitchen to provide food services to organizations within the Town of Petrolia.