Liddament M W.
Bibliographic info:
5th AIVC Conference "The implementation and effectiveness of air infiltration standards in buildings" Nevada, US, 1-4 October 1984


Airtightness and ventilation standards are forming an increasingly important role i n building energy conservation strategies. Such standards were first introduced in Sweden where limited indigenous energy resources, coupled with a severe climate and a steadily increasing reliance on imported energy resources, resulted in a thorough appraisal by the Swedish government of future energy policy. The cornerstone of this policy is building energy conservation with a particular emphasis on the control of fresh air exchange rates. Subsequently, other countries have focussed attention on airtightness and ventilation standards as a method of minimising heat loss from buildings. The purpose of this paper is to explore the implications and cost effectiveness of these requirements, particularly in relation to climate and ventilation needs. The objective is to show that universal standards may not necessarily be appropriate and that it is necessary for each country to pay careful attention to its own individual requirements. In particular, two fundamentally different approaches to the problem are considered. The first relates to a total airtightness policy, in which all fresh air needs are met by mechanical ventilation. While this method can provide ideal control, and can be attractive in terms of national energy conservation, it is not so easy to justify in terms of cost effectiveness especially in mild climates. Thus, where many competing demands are being placed on energy conservation budgets, this approach is unlikely to be adopted. The second method is to introduce limited airtightness measures to restrict excessive air infiltration rates. Again, it is shown that the value of this approach is governed by climate but, if properly introduced, has an important role to play in both new building design and retrofit programmes.