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  Roof ventilation

New Zealand houses and their roof spaces are becoming more airtight. Without proper moisture management, this can lead to a build-up of moisture and issues with mould. Roof space ventilation can reduce the risk of these problems.

These factsheets cover risk factors to watch out for, how to tackle moisture transfer into roof spaces, the air permeability of ceilings and ceiling penetrations, and designing roof space ventilation.

The four factsheets are:

  1. Roof space ventilation in New Zealand houses
  2. Testing the airtightness of residential roof spaces in three dwellings
  3. Air permeability of common New Zealand ceilings and ceiling penetrations
  4. Moisture and ventilation in skillion roofs