Substrate preparation
Uneven masonry, friable coatings or local repairs can add £15–£45/m² before the insulation system is installed.
Insulation thickness
Increasing board thickness by 50 mm typically raises the overall rate by about 5–12%, depending on material and fixing length.
Openings and interfaces
Dense window layouts, deep reveals and abutment detailing can increase the elevation rate by 15–30%.
Access strategy
Complex scaffolding, mast climbers or restricted loading arrangements can add £20–£60/m² to the façade package.
Fire performance
Cavity barriers, fire-break zones and non-combustible specifications commonly add £10–£30/m², with greater premiums on taller buildings.
Finish selection
Premium textures, coloured silicone finishes or brick slips can increase cost by £20–£140/m² compared with a standard thin-coat render.