Victorian Retrofit - Unity Lime

Victorian Retrofit – North Oxford

In 2022 this Victorian semi-detached home undertook a large renovation to upgrade the overall performance of the house significantly.

Firstly, the basement floor was insulated using Glapor foam glass aggregates and finished with a limecrete slab. The walls of the basement were then insulated using Cork insulation boards due to their excellent moisture and anti rot properties.

The ground floor had all the existing cementitious plasters hacked off of the walls before a levelling coat of RK38 lime plaster was applied. Following this woodfibre insulation boards were adhered to the wall using RK70 lime adhesive. The boards were then fixed back to the wall using thermally broken H3 fixings to avoid thermal bridging.

Additional meshing is used around the corners of doors and windows to help prevent cracking from occurring at structural weak spots. Additional corner protection is recommended for use at all corner junctions. The mesh in these locations is applied using small amounts of RK70 to help with embedment.

RK70 was then applied at 5-7mm for a base coat with an embedded reinforcement mesh. Then a further application of RK70 is applied at 3-4mm to get a smooth but rustic lime finish that is in character with the properties history.

The IWI lime plastered woodfire system wall also used on the first floor of the building. Below you can see the application of the plaster-able PAVAFIX WIN variable Sd tape.

Finally, the roof and floor joists were thermally upgraded using Pavatextil-P recycled denim insulation. This product has excellent acoustic properties as well as great thermal conductivity values of 0.039w/m2K

The rafters were finished on the underside of the roof with ISOLAIR woodfibre boards, these were then plastered with the same RK70 2 coat system to provided a consistent lime finish throughout the build.