| Berkeley Homes |
| BJB (UK) Ltd |
| Black Country Housing Group Ltd |
| blooming green |
| Borough Council of Ling's Lynn and West Norfolk |
| Bosch UK |
| Bovis Homes |
| BR Testing Ltd |
| BRD Tech Ltd |
| BRE |
| Brent Private Tenants Rights Group |
| Bright Green Energy |
| Brighton and Hove City Council |
| Bristol DEA |
| Bristol Debt Advice Centre |
| British Gas |
| British Gypsum |
| British Plastics Federation Windows Group |
| British Property Federation |
| British Pump Manufacturers' Association (BPMA) |
| British Retail Consortium |
| British Urethane Foam Contractors Association |
| British Woodworking Federation |
| BRUFMA |
| BSkyB |
| Builders Merchant Federation |
| CAG Consulting |
| CALA Group Ltd |
| Cambridge Architectural Research |
| Cambridge City Council |
| Camco |
| Camden Federation of Private Tenants |
| Capita Symonds |
| Carbon Action Network |
| Carbon Control Limited |
| carbon saver ltd |
| Carbon Special Reserve |
| Cavity Insulation Guarantee Agency |
| CDCE Ltd |
| CEA |
| CEN |
| Centre for Alternative Technology |
| Centre for Sustainable Energy |
| Ceres Power |
| Changeworks |
| Chartered Institute of Housing |
| Cheshire & Merseyside ESTAC |
| Chesterfield Borough Council |
| CHPA |
| CIBSE |