Title of the project: Paint finish investigation of Blue House, Blue House Cluster, Stone Nullah Lane, Wanchai, HK
Project lead: Gesa Schwantes
Project team: Gesa Schwantes; Kristina Kong (student helper BA Conservation)
Project funder: St. James’ Settlement, 85 Stone Nullah Lane, Wanchai , HK
Project type: Contract Research
The Blue House Cluster is a group of shop houses or tenement buildings including the Blue House, Grey House, Yellow House and Orange House. The site is bounded by Stone Nullah Lane to the west, Hing Wan Street to the south, King Sing Street to the north and a back lane to the east, in Wanchai, Hong Kong.
The four shop houses of Blue House at 72-74A Stone Nullah Lane were constructed in 1920s. It was designated grade 1 historic building by Antiquities Advisory Board (AAB). The four shop houses of Yellow House at 2-8 Hing Wan Street were built in 1920s. It was accorded as grade 3 historic building. The single lot Orange House at 8 King Sing Street originally built in 1930s was substantially rebuilt between 1950s and 1960s. The Orange House has no grading status. The Development Bureau (DEVB) launched in mid 2009 the Revitalising Historic Buildings through Partnership Scheme (Revitalisation Scheme) Batch II, which allow the Non-Profit-Making Organization (NPO) to revitalise Government-owned historic buildings. The secretary for Development issued an approval-in-principle to the proposal of Viva Blue House project submitted by St. James’ Settlement.
Project Scope ACLab:
After the completion of the paint finish analysis for Grey House in March 2015, the St. James settlement applied for funding to complete the paint analysis of the Blue House as well. The Architectural Conservation Laboratory was invited to submit an updated quotation for investigations at the Blue House.
Same as for the Grey House, the building fabric of the Blue House is in an extremely poor condition due to total lack of maintenance work and inappropriate and damaging maintenance using cement plaster for repair patches. The blue paint applied by the government in 1997 was painted roughly over the entire building on top of rust, weathered wood and damaged façade plaster without any repair measures apart from local plaster repairs. These repairs, however, were carried out with hard cement plaster, not compatible with the softer original lime plaster of the building.
The paint finish investigation shows, even though with limited evidence due to the poor condition of the weathered building surfaces, that the entire block, Blue and Grey House, were painted with analogical finishes and their paint finish history is very similar in earlier years. It started to diverge from the 1970ies when the Blue House was surrendered to the government, while the grey house remained in private ownership.
The sketch shows the original colour scheme according to investigations of finishes at Blue and Grey house:
Walls: Lime plaster substrate, yellow lime wash or ferrous sulphate solution.
White or off white lime finishes for coping, banding, corbel brackets, balcony ceilings, windowsills and window hoods.
Joinery: Green oil paint on windows and doors; transparent oil or varnish finishing of the wooden balcony hand railings (only few remaining today)
Metalwork: Probably green, maybe black finish (very limited material evidence due to poor, extremely rusted condition)
It appears that the Blue House will be kept blue, as the building gained certain famousness as conservation project of historical shop houses in HK. From a conservation perspective this decision is justifiable, however the paint material has to be changed form the current synthetic paint finish to mineral finish in order to preserve the original fabric. The porous materials of the substrate, the brick wall with lime render and lime based finish, should be painted with a lime or silicate based paint.
The project will be used as a case study example in a paper on challenges in integrating scientific investigations in building conservation projects in Hong Kong. An abstract has been submitted to the Journal of Housing and the Built Environment in February 2016 pending acceptance.