Skillion Roof Ventilation Nz

Nzmrm and underlay manufacturers believe the answer lies in increasing what is currently the non existent ventilation of roof spaces.

Skillion roof ventilation nz.

There are only two ways to remove moisture from any container ie your home. The roof space is generally inaccessible with little natural ventilation and the small roof space can accelerate problems with moisture. A skillion pitched roof of any degree pitch requires continuous airflow of 25 000mm per lin m at eaves level unimpeded airflow through the roof cavity and ventilation at the ridge. Ventilating the roof cavity in this way will ensure that internal moisture is greatly reduced in the roof cavity which safeguards the roof from damp mould and structural decay.

Mammoth skillion sections are designed to promoted high thermal performance in modern skillion roof designs. Roof and under deck spaces share the same construction materials and similar construction techniques as walls which have in the past failed from the ingress of moisture lack of drainage and ventilation to dissapate moisture that has entered the internals of the wall roof itself. Whilst it is possible to retrofit passive ventilation solutions to existing buildings it is highly recommended to incorporate passive ventilation during the design phase of any new building project. Especially in systems like skillion roofs and curved roofs.

Our systems are structured and specifically tailored for new zealand buildings and the extreme climatic conditions. In high wind zones the placement of vents in metal and tile clad skillion roofs might not be critical. Some roof designs such as skillion roofs must include ventilation to manage roof moisture. Achieving calculated continuous and unimpeded airflow through the roof cavity is relatively straight forward.

Skillion roofs need carefully designed and installed ventilation to reduce the risk of moisture related problems. Vent was created as a direct result of the misconception that the leaky homes disaster that gripped new zealand was caused solely by external moisture penetration and product failure. We have approached dbh and branz to request an urgent investigation into this issue so far without result. In skillion roofs the roof cladding and ceiling run parallel typically within 300 mm of each other.

Ventilating a home with no roof cavity a flat roof or a skillion roof design is something that should be planned prior to building and should involve a ventilation specialist and the architect who both understand each others point of view and the needs of the client. Recent branz research provides advice on the best place for effective vent openings in low wind zones.