A building’s airtightness test result isn’t just an indicator of its energy efficiency – it’s an unambiguous indicator of build quality. With a little care in design and on site, airtightness targets that may seem impossibly tough are anything but, argues leading architect and certified passive house designer Simon McGuinness.

Turning a ruined farm house into a usable dwelling has been a dream for decades, but can an age-old structure really be brought-up to the cutting edge of energy efficiency? Architect Frank Cooney has found a way with a ruin in Cavan currently undergoing renovation. Jason Walsh visited the site to find out more.