Do not make the house too air-tight. In addition to normal fresh air requirements, an outlet for elements such as tobacco smoke; moist air from cooking, washing and breathing; fumes from gas stoves and unvented gas or kerosene heaters; and fumes from paints, cleansers and adhesives must be taken into account.
It is therefore also important in a weathertight house to periodically use some controllable means of ventilation, such as a window or an exhaust fan.
Draughts can be prevented by sensible location and design of the house,
sound building construction, and weatherstripping.