BG 2/2008 covers all forms of ventilation, from simple openable windows to mechanical ventilation systems with complex heat recovery systems. BSRIA's guide covers allied subjects such as: use of a building's thermal mass in order to maintain a steady temperature; the growing use of ground-coupled ventilation and thermolabyrinths, which perform a similar function; buoyancy-driven flow and stack ventilation; commissioning; night cooling; ways to minimise cooling loads; and risks and downsides of natural and mechanical ventilation systems.