The current standard skillion roof detail is often from the outside towards the inside metal roof cladding roof underlay purlin insulated rafters with a 25mm air gap and internal lining.
Skillion roof details nz.
The building in the model has a 12 m long roof with 300 mm deep eaves.
Skillion or exposed rafter roofs were framed up on site.
If you would move the detail above into a vertical position it would be like an external wall with vertical metal cladding.
Skillion roofs skillion roofs incorporated a ridge beam or internal loadbearing wall to support the roof apex and generally had the ceiling lining fixed to the underside of the rafters with the roof cladding installed as done when there was a roof space.
Share in skillion roofs the space between purlins and insulation is usually limited to 25mm meaning airflow below the roofing underlay is extremely restricted.
The dimensions of the building are not critical and chosen only to show the effect.
Airflow simulations were carried out for a monopitch skillion roof with profiled metal roofing with and without eaves.
Skillion roof airflows modelled.
Off site roof framing consisted of prefabricated timber trusses while on site roof framing consisted of a framework of rafters ridgeboard or a ridge beam underpurlins and underpurlin struts and collar ties and cleats.
Roof skillion vented ridge cap w1111 1 typical valley detail counter battens w1121 1 1 skillion eave vented soffit w1131 1 skillion eave vented fascia w1131 3 skillion eave solitex um w1133 skillion eave solitex um a1133.
Pro clima nz ltd.
Vent s passive ventilation systems for skillion roofs have been designed to create continuous calculated unimpeded airflow that can exit the roof cavity.
The roof space is generally inaccessible with little natural ventilation and the small roof space can accelerate problems with moisture.