NatVent™ is a seven nation pan-European project which aims to reduce primary energy consumption (and consequently C02 emissions) in buildings by providing solutions to barriers which prevent the uptake of natural ventilation and low-energy cooling in countries with moderate and cold climates. It also aims to encourage and accelerate the use of natural ventilation and 'smart' controls as the main design option in new-designs and major refurbishments of office-type buildings.

The paper is structured in four sections. The introduction sets the notion of solar control as a fundamental issue in deciding the priorities of climate-responsive design for different building types and locations in Europe. The second section presents an overview of application contexts and means of solar control, and discusses design priorities and threshold conditions for different space functions and environmental design requirements.

The current recommended minimal ventilation level for the cold deck flat roof design is evaluated using an experimental roof. The work suggests that there may be a need for ventilation to be increased above the minimal level in instances where natural draught ventilation is low or where roofs are of complex plan. Results of this work are under consideration by the British Standards Institution as part of an overall review of flat roof design recommendations.

Passive stack ventilation is a means of removing unwanted moisture from dwellings. The proper design and installation of these systems is vital to their successful performance. This paper gives detailed guidance on this subject and is in support of the 1995 edition of the Approved Document to Part F of the Building Regulations.

Fungal spore content in dust accumulated in air ducts was investigated in 24 mechanically ventilated single-family houses of which 15 had also a central air heating system. Dust was collected from the ducts simultaneously with cleaning of the ventilation systems. Besides spore concentrations and flora of culturable fungi, total fungal spore concentrations were determined in dust samples by the aqueous two phase technique and spore counting with epifluorescence microscopy.