21 Degrees Information

At 21 Degrees, we believe buildings should be designed for lower energy use, healthier spaces and better comfort. We help homeowners, architects, developers and businesses take a whole-house approach to building performance, bringing together windows, heating, ventilation and renewables in one joined-up design. Our services include solar PV, heat pumps, battery storage, triple-glazed windows and doors, mechanical ventilation with heat recovery (MVHR), insulation and airtightness solutions. 21 Degrees brings together the heritage and expertise of specialist businesses including Green Building Store, founded in 1995, and Green Building Renewables, an award-winning renewable installation company. We have been part of the UK low-energy building movement for three decades, supporting the growth of Passivhaus since 2007 and completing the UK’s first cavity wall Passivhaus at Denby Dale in 2010.