This is the second instalment of our guide running from concept to handover, what needs to happen at each RIBA stage to achieve a successful airtightness test.

We need to retrofit millions of buildings with airtightness and insulation to achieve net zero. What is EnerPHit compared to Passivhaus, what are passivhaus principles? We give an introduction to highly efficient construction renovation projects.

Insulation stops heat escaping by blocking conduction. But it can’t do its job properly if heat is also being carried away by unwanted air movement.