Decra Roofing Resource Centre, over 30 year’s experience of finding the right lightweight roofing solutions

Warm Roof Constructions - Duo-pitched roofs with clear air path

Duo pitch roof with clear air path
Where underlay/breather membrane is to be installed on top of counterbattens.
Where 50mm air passageway between insulation and underlay/breather membrane occurs below the top face of the rafter. 




Eaves ventilation with a continuous opening equal to 25mm. Free airspace between insulation and underlay of at least 50mm.
Ridge ventilation with a continuous opening equal to 5mm at each side of ridge.
Note: in addition to a well seated ceiling, a separate vapour control layer should be used on the warm side of the insulation..

Decra Solution:


i) DecraVent 25mm Eaves Packs, each pack providing ventilation for 6 metres of eaves, installed to provide continuous ventilation to both eaves.
Alternatively: Tile vents at appropriate centres to provide equivalent of a 25mm continuous opening.

ii) Decra Universal Ridge/Hip Ventilator (all Decra tile profiles) or DecraVent D Ridge system (Decra Classic and Noxite Tile only) providing continuous ridge ventilation.

Alternatively: Tile vents at appropriate centres to provide equivalent of a 5mm continuous opening.

Quick Links

Decra Eaves Ventilation System:
Which is the right eaves ventilation system for your roofing project? 
Read more 

Ridge Ventilation Components:
Which is the right ridge ventilation system for your roofing project?
Read more

Tile Ventilation Components:
Read more about the range of tile ventilation components and their order codes

Tile Ventilator Spacing Charts:
Recommended tile ventilation spacing's to achieve 5,000mm², 10,000mm² or 25,000mm² per linear metre please click on the appropriate link below

Decra Classic and Noxite Tile

Decra Stratos and Oberon Tiles


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