We are working on a few grade II listed properties, including a lovely semi-detached house in Llandaff which had a complete overhaul to convert it from the two 'tired' flats back into a family home. The house had bad mould growth, an antiquated heating system and very drafty windows with single glazing and had been empty for two years. The client was keen to have a 'deep retrofit' and to make it more sustainable, restoring the house to its former glory.
However because the house is Grade II listed and within the Llandaff Conservation Area all work had to be carefully considered and with the agreement of the council's Conservation Officer. The house was designed as a pair with it's neighbour St Cross by the ecclesiastical Architect Ewan Christian in 1869-61 in a restrained Gothic Style for the Minor Cannons of the Cathedral. Together, the houses have ornate stepped gables and multicoloured stone walls with a mix of timber sash and steel windows (many with original diamond leaded glass remaining in St Andrews. The interior of the house was fairly restrained by the Victorian standards of the day - more Georgian and plain. Most of the original fireplaces had been removed, but many of the stepped cornices, chamfered detailing remained as well as the original staircase.
The problems in the house had been caused by the previous tenant sealing the solid stone walls with cement plaster which didn't allow them to breath and the rooms having insufficient ventilation - particularly in the bathrooms and kitchens with sporadic heating.
The deep retrofit involved stripping back the external walls to the bare (solid) stone and installing breathable insulation and with lime plaster. The stone window surrounds had to be left exposed, but where possible the windows were repaired or replicated with ultra slimline 'Histoglass' double glazing (the outer pane in 'old style' hand drawn glass). The two smaller rooms at the back and the outside toilet were merged into one with a new 'breathable' insulated limecrete floor and underfloor heating. The ventilation was improved with the installation of a whole house ventilation system to wall rooms with new lead ventilation cowls in the rear roof. The heating is provided by two air source heat pumps in the rear garden with the remainder of the plant located in the small basement.
The traditional detailing internal with timber beads and chamfers was restored throughout and the client replicated the only original fireplace, in stone for two of the other primary rooms.
The work took nearly a year to complete, mainly because of the time taken for the many layers of the lime plaster to dry. The contractor was Pithers Construction and the finished result is to a very high standard, transforming the house into a comfortable home.