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 Interstitial Moisture

Roof experiments

We have built an outdoor test facility to continuously monitor full-scale commercial and residential roof specimens (for temperature, relative humidity and heat flux) to investigate the complex issues related to the formation and removal of interstitial moisture in roof spaces.

A main focus is the role of ventilation on the dynamics of interstitial moisture in roof spaces:

  • How much roof ventilation is required to prevent moisture problems?
  • If extra ventilation is required, what are the best ways to provide it?

This experimental work will be supplemented by field ventilation surveys in residential and commercial environments. These will give a snapshot of the level of ventilation currently present and provide essential information for the test facility and the subsequent modelling effort.

Recent results on commercial roof structures - characterised by a large cavity often with steel framing - are summarised in a study report and will be presented at the BABNZ conference in September 2014.

Present work is focusing on moisture and ventilation in skillion-type residential roofs.