Question to the Department for Business, Energy and Industrial Strategy:

To ask Her Majesty's Government what assessment they have made of the quantity of insulation material needed to insulate the entirety of the UK’s building stock in time to meet the 2050 Net Zero target.

The English Housing Survey provides estimates[1] of the extent of different insulation measures in the English housing stock. These estimates suggest that 6.3m solid walls remain uninsulated, 5.4m cavity walls remain uninsulated, and 3.2m lofts have less than 100mm of insulation (this figure excludes homes that do not have a loft – for example, homes with a loft conversion). Only 1.9m homes currently have floor insulation.

It should be noted, particularly for higher cost measures like solid wall insulation, that not all these untreated properties need to be improved, as some of these improvements would not be considered cost effective, practical or affordable on an individual property basis. Energy efficiency is a matter for the devolved administrations, who will have equivalent estimates for their countries.

[1]https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/898342/Energy_Chapter_2_Figures_and_Annex_Tables.xlsx, tabs: AT2.10, AT 2.11, and AT2.12