Time-use in different rooms of selected New Zealand houses and the influence of plan layout

House interiors are affected by outdoor and indoor pollutants although levels of exposure differ with room type. The times people spend in rooms also differ, and hence their potential level of exposure, which is the focus of this article. Additionally, time spent in a kitchen during cooking, which is the main source of indoor particulates for non-smoking households, could affect indoor air quality in other rooms, especially where the kitchen is part of an open plan arrangement. This study investigated the time people spend in all rooms including kitchens and open plan kitchen/dining/living in New Zealand houses. On average, New Zealanders spend 54% of time at home indoors in usual bedrooms and 29%-36% in a living room, dining room, and kitchen (or combination of these). People in open plan houses spend less time in living areas than those in cellular plan houses, but effectively more time in the kitchen'. Given time spent in a combined living room/dining/kitchen, combined living room/kitchen or combined dining room/kitchen is effectively time spent in a kitchen, people spend respectively 3.23, 1.36 and 0.53h/day more in the kitchen compared to those having a separate kitchen, which could increase their chance of exposure to kitchen pollutants.